Re: [time-nuts] Cesium Clock Avialable

[Mike Feher]

Along the same lines, I wonder how long a new tube can last on the shelf? About 
16 years ago I bought a 5061A on eBay. When I received it I noticed the tube 
was replaced and still had 2 years on the warranty. It worked just fine. The 
only problem was the battery charging circuit. Wanting to make it perfect, I 
started working on repairing it. Needless to say, it is still apart due to a 
separation in 2013 and a divorce in 2015. I have not touched it since 2012. For 
me, at 73 now, stairs are not much fun and my old lab is in the basement, but, 
I wonder if I did brave to go down there would it be worth playing with it 
again. Thanks for any observations in this regard. Regards – Mike 

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

-Original Message-
From: time-nuts  On Behalf Of Pete Lancashire
Sent: Saturday, May 19, 2018 11:39 AM
To: Discussion of precise time and frequency measurement 
Subject: Re: [time-nuts] Cesium Clock Avialable

 

Dana,

 

I would suggest downloading and reading the HP journals that discussed the 
first clocks there's a lot of information in there about how they operate Etc.

 

On Sat, May 19, 2018, 8:23 AM Dana Whitlow <  
k8yumdoo...@gmail.com> wrote:

 

> Don't Cesium clocks have a beam current integrator of sorts so that 

> it's possible to pretty accurately assess the remaining life of the 

> tube?  If not, I'm terribly surprised and disappointed.

> 

> Also, beginning with a new tube, roughly how long can one be run until 

> it reaches exhaustion?  Are we speaking months, years, decades, or what?

> 

> Dana

> 

> 

> On Sat, May 19, 2018 at 10:01 AM, Bob kb8tq <  
> kb...@n1k.org> wrote:

> 

> > Hi

> >

> > Unfortunately there really is no way to tell how much Cs is left in 

> > the tube. You can look at beam current and make a guess. All that 

> > really will tell you is that the fuel gauge is on empty or at least 

> > just off of empty.

> >

> > Bob

> >

> > > On May 19, 2018, at 2:30 AM, Paul Bicknell 

> > > <  p...@bicknells.f2s.com>

> > wrote:

> > >

> > > Hi Doug

> > >

> > > Is it possible to test its operation and

> > > can the time left on the cesium be calculated   Regards Paul

> > >

> > > -Original Message-

> > > From: time-nuts [  
> > > mailto:time-nuts-boun...@febo.com] On Behalf Of 

> > > Doug

> > Millar

> > > via time-nuts

> > > Sent: 19 May 2018 05:04

> > > To:   time-nuts@febo.com

> > > Subject: [time-nuts] Cesium Clock Avialable

> > >

> > > Hi, I am willing to part with my HP 5061A cesium standard and manual.

> The

> > > unit was rebuilt and functioning some years ago and not used since

> then.

> > > There is usable cesium in the tube and the unit worked. I have not

> > tested it

> > > recently. It has a Patek-Philippe analogue clock in the front. The 

> > > unit

> > is

> > > in great physical condition.  Asking $600 plus shipping from Long

> Beach,

> > CA.

> > > 90806

> > > I also have an ESI 242D resistance calibrator and a Julie primary

> > resistance

> > > standard in an oven. Let me know if you are interested. Very

> reasonable.

> > >  Thanks, Doug K6JEY

> > > ___

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> > >   
> > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts

> > > and follow the instructions there.

> > >

> > >

> > > -

> > > No virus found in this message.

> > > Checked by AVG -   www.avg.com

> > > Version: 2016.0.8048 / Virus Database: 4793/15670 - Release Date:

> > 05/19/18

> > >

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Re: [time-nuts] Anybody have suggestions for time related science fair projects?

[Mike Feher]

How about a Stroboscope? - 

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

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Re: [time-nuts] Dual GPSDO - any advantage?

[Mike Feher]

Sounds to me like you have two independent systems. I do not believe they can 
ever be “coherent”. Regards – Mike 

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

-Original Message-
From: time-nuts  On Behalf Of donald collie
Sent: Tuesday, April 10, 2018 1:43 AM
To: Discussion of precise time and frequency measurement 
Subject: [time-nuts] Dual GPSDO - any advantage?

 

I`ve just bought two GPSDO`s from China @ US$9-50 each [This is not an error!] 
They are stated as being new, and use a Trimball dual oven OCXO. I plan to run 
these in parallel [2 antennas, 2 feedlines, and 2 GPSDO`s] It`s been said that 
a man with two watches is never happy - unless, of course, they agree with each 
other ;-). Being identical the outputs should be coherent, unless one becomes 
faulty [one advantage of having two - any discrepancy and you know something 
must be wrong]], but is there some crafty way I can squeeze a little more 
"accuracy" out of two than if I only used one?

TIA for your commentsDonald

Brett Collie ZL4GX

 

PS : I have no connection to the eBay seller. The US$9-50 seems to include a 
basic puck antenna, long downlead, and 4 interseries adaptors 
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Re: [time-nuts] Fwd: HP10811 Oscillator Thermal Fuse

[Mike Feher]

Respectfully I disagree. I have totally shorted out numerous oscillator’s fuses 
with no problems. The design of those thermal fuses makes them vulnerable to 
opening just due to years of use without problem, in any of the electronics. My 
shorted out oscillators still work. Ideally, if handy, it is easy enough to 
replace them if one is available. They just plug in. If there is a thermal 
runaway, that caused the opening, to me that implies that there are other 
issues. Regards – Mike  

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell, NJ, 07731

848-245-9115

 

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Donald E. Pauly
Sent: Tuesday, May 09, 2017 9:49 PM
To: time-nuts; Donald E. Pauly
Subject: [time-nuts] Fwd: HP10811 Oscillator Thermal Fuse

 

  
https://www.febo.com/pipermail/time-nuts/2017-May/date.html

 

I disagree about permanently jumpering the thermal fuse.  The oscillator is 
rated down to -55° C and the oven can maintain 82° C at that temperature.  This 
is a 137° C rise.  It is likely capable of more heat than that.  At 25° C, it 
would therefore be able to reach at least 25+137=162° C.  This is near solder 
melting temperature and would quickly cook the components.  It is rated to work 
at 71° which would give a temperature of 208° C and do serious damage.  That 
thermal fuse is very important.  There are a dozen failures which could result 
in a thermal runaway.

 

This web page discusses the fact that a thermal fuse should be 30° C above 
normal operating temperature to prevent nuisance blows.

 

 http://www.simonsdialogs.com/2016/09/a-thermal-fuse-and-hp-10811-60111-repair/

HP originally used a 26° C margin and later changed it to a 33° margin.  This 
explains the frequent failures.  This poster used the wrong type of fuse but 
the correct type is commercially available.

 

πθ°μΩω±√·Γλ

WB0KVV

 

-- Forwarded message --

From: Bob kb8tq <  kb...@n1k.org>

Date: Mon, May 8, 2017 at 6:07 PM

Subject: Re: [time-nuts] HP10811 Oscillator Thermal Fuse

To: Discussion of precise time and frequency measurement < 
 time-nuts@febo.com>

Cc: "Donald E. Pauly" <  trojancow...@gmail.com>

 

Hi

 

You will get a lot of diversity of opinion on the topic of the thermal fuse on 
the 10811. My feeling is that they are a nuisance and contribute very little to 
the design. I’d just short it out and move on. In the era of failure prone 
heater transistors or faulty thermistors, the fuse may have made sense. That 
era ended before the

10811 went into production.

 

Bob

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Re: [time-nuts] Vintage Quartz Crystal Manufacturing

[Mike Feher]

Wow, those are really neat. I have several hundred different style holders in 
my collection, but, I have never seen any like those. Thanks for sharing. Now 
to find one :). Regards - Mike 

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
848-245-9115

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Adrian Godwin
Sent: Saturday, November 26, 2016 7:41 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Vintage Quartz Crystal Manufacturing

I bought some old crystals on ebay :

http://www.ebay.co.uk/itm/15114483

Is anyone familiar with this style ? I don't think the quartz is visible in the 
glass section : I imagine that's just an insulator. I think the quartz is under 
a brass disc, with a sping to hold the disc down visible through the glass.

Does anyone know what the reference marked on them "w'less sets No 7"
refers to ?


On Mon, Sep 26, 2016 at 6:50 AM, Mark Sims  wrote:

> Can you say "Mr Rogers' Neighborhood?"   I knew you could...
>
> He (along with creepy Mr McFeelie) always ran segments on how some item
> was made.   Geared towards pre-schoolers, but always worth watching.
>
> -
>
> Compare the Science channel's new "How Do They Do It" to the older 
> "How It's Made"
> shows.
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Re: [time-nuts] Diophantine frequency synthesis articles

[Mike Feher]

Wow, the last time I heard of this word was in the late 60's in a graduate 
course on number theory. I still remember the story of the monkey and the 
coconuts :). Admittedly I did not look at any of the posted links, but, have no 
 idea how Diophantine equations can help frequency counters. Regards - Mike 

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

That is interesting. We always used -174 and not -177 as it was concluded that 
at those low levels AM and PM noise are not discernible, so, the total noise 
density per Hz was -174. This must be relatively new since I worked in 
industry. We had a bunch of PhDs from Lincoln helping as well and they always 
used -174. This sounds like one of those instrument manufacturers gimmick to 
make the numbers look better :). 

Your last statement is why I started to question the claims initially. - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of John Miles
Sent: Thursday, August 11, 2016 7:57 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

-177 = the -174 dBm/Hz SSB thermal noise floor at 25C, less 3 dB to account for 
the usual assumption that half of it is AM, half PM.   

dBm/Hz is obviously equivalent to dBc/Hz for a 0 dBm carrier.  

Anyone who claims to measure noise in a 1 Hz bandwidth below -177 dBm/Hz at 
room temperature is either doing something wrong somewhere, or doing something 
amazing somewhere.

-- john, KE5FX
Miles Design LLC

> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike 
> Feher
> Sent: Thursday, August 11, 2016 4:15 PM
> To: 'Discussion of precise time and frequency measurement'
> Subject: Re: [time-nuts] State of the art of crystal oscillator 
> measurements
> 
> That is why I asked what the Po was. Where did the 177 come from? L(f) 
> is single sided. This is not my first "rodeo" in these matters. 73 - 
> Mike
> 
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ, 07731
> 732-886-5960 office
> 908-902-3831 cell
> 

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

That is why I asked what the Po was. Where did the 177 come from? L(f) is 
single sided. This is not my first "rodeo" in these matters. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of John Miles
Sent: Thursday, August 11, 2016 4:22 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

Remember that L(f) is expressed in dBc/Hz, not dBm/Hz.  If it were dBm/Hz, then 
kT would be the limit.  But in dBc/Hz terms, the limit is 177 + the DUT's 
output power in dBm.  

Assuming a 50 ohm system, of course.

-- john, KE5FX
Miles Design LLC


> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike 
> Feher
> Sent: Thursday, August 11, 2016 12:51 PM
> To: 'Discussion of precise time and frequency measurement'; 
> ka2...@aol.com; t...@leapsecond.com
> Cc: enrico.rubi...@gmail.com
> Subject: Re: [time-nuts] State of the art of crystal oscillator 
> measurements
> 
> kT is indeed relevant for a physical implementation. - Mike
> 
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ, 07731
> 732-886-5960 office
> 908-902-3831 cell

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

kT is indeed relevant for a physical implementation. - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Richard (Rick) 
Karlquist
Sent: Thursday, August 11, 2016 1:40 PM
To: Discussion of precise time and frequency measurement; ka2...@aol.com; 
t...@leapsecond.com
Cc: enrico.rubi...@gmail.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements



On 8/11/2016 5:01 AM, Mike Feher wrote:

> This may be a naive question, but, how can you achieve results that 
> are so close to, and sometimes at further out are below kT? Thanks & 
> 73 - Mike

> Mike B. Feher, EOZ Inc.
>

kT per see is not the relevant parameter.  It is the ratio between kT and 
signal level that determines the limit on phase noise.  Also, when you extract 
an oscillator signal through the resonator, then at offsets from the carrier, 
the resonator filters out noise and the output noise can be way below kT.  
Ulrich first published on this in 1977.  Earliest reference I know of.
I actually remember reading it in 1977.

The old HP608 signal generator routinely produced far out phase noise floor 
well below kT.  AFAIK, for this particular spec, it better than any other 
signal generator ever built.  What's the secret?  It has a tracking 
POST-selector filter that follows the oscillator when you turn the mechanical 
tuning knob.  There is a little tracking adjustment knob to peak it.  Not 
really magic.

Rick
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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

Ulrich -

 

This may be a naive question, but, how can you achieve results that are so
close to, and sometimes at further out are below kT? Thanks & 73 - Mike 

 

Mike B. Feher, EOZ Inc.

89 Arnold Blvd.

Howell, NJ, 07731

732-886-5960 office

908-902-3831 cell

 

From: ka2...@aol.com [mailto:ka2...@aol.com] 
Sent: Thursday, August 11, 2016 7:03 AM
To: time-nuts@febo.com; t...@leapsecond.com
Cc: enrico.rubi...@gmail.com; mfe...@eozinc.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

 

Good morning,

 

the difference between the two phase noise FWSP systems is the lower noise
internal 10 MHz reference crystal  oscillator (optimized )  as well as also
some of the internal FSWP circuits custom  optimized . The output power was
17 dBm, but we also have build one oscillator with  12 dBm output power and
noise  similar values.

 

This is part of a PhD project which I supervise .   For values so close to
the carrier you need a very low noise power supply and a well shielded
Faraday cage . The measurement with ca 100  correlation took about 2 hours.
Also the heating circuit needs to be low noise and well decoupled .

 

The 100 Hz value of the better analyzer seems suspicious , It needs to be
further  investigated.

 

All very exciting and time consuming .

 

Ulrich 

 

 

 

 

 

In a message dated 8/10/2016 11:02:25 P.M. Eastern Daylight Time,
mfe...@eozinc.com writes:

These seem extremely fantastic results for a 100 MHz oscillator. I am
curious what the Po of the oscillators are Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van
Baak
Sent: Wednesday, August 10, 2016 9:19 PM
To: Discussion of precise time and frequency measurement
Cc: enrico.rubi...@gmail.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

Attached is a GIF of the table Ulrich wants to share.

Note time-nuts is a plain text mailing list so any rtf or html formatting is
discarded.
On the bright side, PDF or data or image attachments are allowed with no
problem.

/tvb

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

These seem extremely fantastic results for a 100 MHz oscillator. I am curious 
what the Po of the oscillators are Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van Baak
Sent: Wednesday, August 10, 2016 9:19 PM
To: Discussion of precise time and frequency measurement
Cc: enrico.rubi...@gmail.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

Attached is a GIF of the table Ulrich wants to share.

Note time-nuts is a plain text mailing list so any rtf or html formatting is 
discarded.
On the bright side, PDF or data or image attachments are allowed with no 
problem.

/tvb

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Re: [time-nuts] that's really awesome

[Mike Feher]

Not to worry Tom. I do not think anyone on this reflector is naïve enough to 
actually fall for it. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van Baak
Sent: Wednesday, June 22, 2016 1:05 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] that's really awesome

> I can't imagine anyone following a link that is presented in this way.
> 
> I love a lot of things, how about telling me why, as a time-nut, that 
> I should love it?
> 
> As it is, this looks just like many, many, spambots taking over a list.
> 
> -Chuck Harris

I normally catch spam postings like that one before they go out to the group. I 
missed that one. Sorry.

/tvb

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Re: [time-nuts] GENIUS by Stephen Hawking (PBS TV),

[Mike Feher]

I too enjoyed the show as well as Tom's part in it. However call me "doubting 
Thomas" or in this case Mike, I have the same concerns as expressed by "ws". 
Also, an initial comparison of the two used, at low altitude, to show an 
unmeasurable difference would have been helpful. All that aside it was great, 
and, I am not smart enough to understand it all anyway. Regards - Mike  

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of ws at Yahoo 
via time-nuts
Sent: Saturday, May 21, 2016 11:37 AM
To: time-nuts@febo.com
Subject: Re: [time-nuts] GENIUS by Stephen Hawking (PBS TV),

Tom
Impressive. Nice job.

How would one go about to prove beyond a doubt in that experiment that 18ns of 
phase shift in 24 hrs was truly caused by freq offset due to Relativity and not 
by some other combination of environment and handling issues that effected 
phase &/or freq once the identical clocks where separated and operating at 
different temperatures, pressures, elevations, vibration, tilt angles, power 
supply voltages, airflow, cosmic rays, ozone, or some other unmeasured things 
that may be effecting the results?

To increase  *gravity* a lot more than a 7,000 ft altitude change, and without 
changing the environment variables, could one set of the CS clocks be put on a 
centrifuge, such as a fast spinning merry-go-round at a local park?

Anyone know what the 2G turn over effect, TC, etc, is of portable CS standards? 
Ideally they should all be zero, but probable aren't.

ws 

 

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Re: [time-nuts] Can a Symmetricom 58532A antenna and ham radio transmitters coexist?

[Mike Feher]

My HP has been on top of the roof for about 15 years. I have a 2 meter antenna 
not far from it with about 200 watts and on half of a 160 meter inverted vee 
slightly higher above it, running full legal power. Never had an issue. 73 - 
Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-bounces+mfeher=eozinc@febo.com] On Behalf 
Of William H. Fite
Sent: Thursday, April 14, 2016 9:07 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Can a Symmetricom 58532A antenna and ham radio 
transmitters coexist?

Good morning, Pete. My 58532 antenna is about 10 meters away from a UHF/VHF 
vertical through which I run up to 50W and about 25 meters from an HF magnetic 
loop which I feed with up to 500W.

I have had no issues with the Symmetricom antenna or the T'bolt that it feeds.

Bill
KJ4SLP



On Thursday, April 14, 2016, Pete Stephenson  wrote:

> Hi all,
>
> I recently acquired a pair of Symmetricom 58532A antennas and so far 
> they work great with my setup (antenna --> Symmetricom 58535A splitter
> --> [1] Thunderbolt and [2] other receivers that I swap out
> occasionally).
>
> I'm also an amateur radio operator and am looking to mount the 58532A 
> on a roof-mounted mast to get better coverage (right now it's outside 
> a window). Would the presence of nearby (either on the mast or within 
> 20m of the mast) HF (3.5-30MHz) , VHF (~145MHz), and UHF (~430MHz) 
> transmitters cause any issues? My transmit power is typically around 
> 5-20W on HF with peaks up to 100W and 1-5W on VHF/UHF. The HF antenna 
> is a simple wire dipole, not a high-gain directional antenna.
>
> Naturally, I'd like to avoid damaging my GPS antenna or any of the 
> downstream devices.
>
> Since the 58532A is currently mounted relatively close to the 
> splitter, I'm using LMR100A coax (it's lossy, but the short lengths 
> mean it's not an issue; the window mount makes the thinness of the 
> cable important) but for the longer run from the mast I'd used LMR240 
> or LMR400 as needed. I use the same type of cable for the HF radio.
> Those cables are well-shielded (braid-on-foil) with >90dB shielding 
> attenuation, so I don't think signal leakage from or ingress into the 
> cables will be a big deal.
>
> The datasheet for the 58532A specifies the out-of-band signal 
> attenuation is around 60dB at +/- 50MHz.
>
> Many thanks in advance for the help.
>
> Cheers!
> -Pete
>
> --
> Pete Stephenson

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Re: [time-nuts] Electronic Goldmine ===> was: Re: DC-DC Converters

[Mike Feher]

I too have bought from them on several occasions. Always found their shipping 
rates high, although nothing as ridiculous like Dave M reported. What irks me 
more, is that often they have something I want on sale but they limit your 
purchase to a single item or very small quantity. 73 - Mike  

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Graham
Sent: Saturday, March 19, 2016 9:01 PM
To: time-nuts@febo.com
Subject: [time-nuts] Electronic Goldmine ===> was: Re: DC-DC Converters

I find Electronic Goldmine shipping quite reasonable and I am in Canada, 
perhaps a wee bit high but not overly.

The sometimes have flat rate or free shipping specials to the US.

Sign up for their email news letter. You will get notice of new items and 
special deals; some special deals are only made notice of too subscribers.

cheers, Graham ve3gtc


On 2016-03-19 21:19, Dave M wrote:
> Goldmine has been around for a bunch of years.  I've bought lots of 
> stuff from them. Most of the time, their prices are significantly 
> below MSRP. They sell first class stuff, usually discontinued items 
> and retailers' clearance items.
>
> Great folks to buy from.  My only heartburn with them is their 
> shipping charges.  They don't seem to have any cut-rate deals with any 
> of the major shippers, but it's not like a bunch of Ebay sellers, that 
> make their money with exhorbitant shipping charges. $50 to ship a 1/2 
> lb. item to the next state is a bit rediculous.
>
> Overall, a good source of good stuff at good prices.
>
> Cheers,
> Dave M

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Re: [time-nuts] PLL book 3rd edition

[Mike Feher]

I agree Ulrich. I was designing FFTs, Digital filters and DDSs in the late 60's 
early 70's through the mid 80's. After that it was discrete PLLs. Had to write 
our own programs for coefficients and use discrete parts most of the time. How 
many design engineers today even know what a Z transform is, or the Remez 
exchange algorithm. It seems except for a very few, the fundamentals are lost. 
BTW, I do have your book, HI. It has been a long time since we chatted on 2 
meters. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of KA2WEU--- via 
time-nuts
Sent: Tuesday, March 08, 2016 11:57 AM
To: rich...@karlquist.com; time-nuts@febo.com
Cc: enrico.rubi...@gmail.com
Subject: Re: [time-nuts] PLL book 3rd edition

yes, but the underlying math and system architecture  will/would be exciting.
 
Thanks, for the comments, Ulrich 
 

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Re: [time-nuts] Looking for OCXO

[Mike Feher]

If you are also bringing an old HP power meter, you could use the calibrator 
out from it. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Nathan Johnson
Sent: Thursday, February 25, 2016 7:47 PM
To: time-nuts@febo.com
Subject: [time-nuts] Looking for OCXO

I'm going to be taking some oscilloscopes to a hamfest this summer, and I am 
going to have a truck full of stuff anyway, and would like to avoid hauling my 
signal generator to provide a demonstration of the scopes. Does anybody have a
50MHZ+ OCXO or other oscillator with a coax(sma/bnc) that they would 
50MHZ+ like
to
part with? Something that doesn't meet time nuts standards is perfectly 
fine,
just want something that is faster than the built in calibrator on the 
scopes.
Nathan KK4REY

Sent using CloudMagic Email
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Re: [time-nuts] Einstein Special on PBS

[Mike Feher]

Bob -

Thanks for attempting to make me see the light. But, I still do not. You said 
it yourself that hyperfine transitions remain the same. Since "time" on these 
device are derived from these transitions, they should also remain the same. I 
agree, from a relativistic point of vie the time will be different. I am just 
not convinced that using these types of clocks will demonstrate that. Thanks - 
Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Stewart
Sent: Friday, November 27, 2015 12:48 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Einstein Special on PBS

Hi Mike,
I'm far from an expert on this, but what you're missing is that time and space 
isn't the same between any two points that are located in different gravity 
gradients and/or moving at different relative velocities.  The hyperfine 
transitions are happening at the same local rate whether the Cs device is on 
planet earth, in orbit around the earth, or in close proximity to the sun or 
even a black hole.  But, all of these examples are happening in different 
space-time environments (i.e. different local frames), so that "relative" to 
each other, they are experiencing time at different rates.

It might help to think of it in terms of doppler effect, though this is not an 
exact comparison.  But, if you have two clocks that are moving away from each 
other, they may very well be precisely synchronous, but because of the doppler 
effect, any measurement you make will show them to be running at different 
rates.  Because of the effects of gravity, watches at different altitudes 
appear to run at different rates to the outsider, although to the person 
wearing the watch, nothing has actually changed; it is the other person's watch 
that is acting funny.

So, essentially, a clock sitting on the ground at sea level is running in a 
very slightly different space time than one that is sitting on a mountain.  And 
when you place a clock in orbit, you also have 14,000 odd MPH of velocity 
that's also having an impact on the space-time of that object.  As a result, 
when you bring the prodigal clock back to sea level, it will have experienced a 
slightly different amount of time than the one at sea level.  Note that the 
prodigal clock hasn't run at a different rate.  It has actually experienced 
time running at a different rate from that of the clock on the ground.

Bob

 

 From: Mike Feher <mfe...@eozinc.com>
 To: 'Discussion of precise time and frequency measurement' <time-nuts@febo.com>
 Sent: Friday, November 27, 2015 9:37 AM
 Subject: Re: [time-nuts] Einstein Special on PBS
   
I just do not get it. I know that now I am 70 and my good smart days are behind 
me, but, this should be simple. In all these clocks mentioned, time is derived 
from the transition of a hyperfine line of a certain atom within some element, 
in this case cesium, In order for any of these clocks to deviate in relative 
time at different heights for example, it seems to me that the period of the 
hyperfine transitions must change as well, to make the defined second longer or 
shorter. So, in these examples the elevation does not change the time, but the 
way the atoms behave. What obvious item am I missing, besides maybe brain 
capacity? Thanks - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Shoppa
Sent: Friday, November 27, 2015 9:19 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Einstein Special on PBS

Would've been more fun to see Tom and his kids going to the top of Mt Ranier in 
2005 with the ensemble :-). http://leapsecond.com/great2005/

They mentioned some "6 miles per day" offset due to GPS relativity effects.
I think this is the sum of both special relativity (time dilation) and general 
relativity (gravitational) effects. The GR correction is 45 microseconds a day 
fast; the SR correction is 7 microseconds slow. 38 microseconds seconds is 11 
kilometers which is indeed 6 or 7 miles. While time drifts 38 microseconds a 
day, I'm not sure that GPS coordinates would drift that fast - aren't most of 
the corrections in the same direction?

Seeing Kip Thorne describe black holes was a blast - he refused to use the word 
mass when describing them, just like when I took a course from him in 1990. 
When my advisor taught the same course, I pleaded with him, "please use 
coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my 
brain does not work that way!!! I would've failed the course if it was only GR; 
fortunately it also had plasma physics in the same quarter, and I was an ace at 
that due to some undergraduat

Re: [time-nuts] Einstein Special on PBS

[Mike Feher]

I just do not get it. I know that now I am 70 and my good smart days are behind 
me, but, this should be simple. In all these clocks mentioned, time is derived 
from the transition of a hyperfine line of a certain atom within some element, 
in this case cesium, In order for any of these clocks to deviate in relative 
time at different heights for example, it seems to me that the period of the 
hyperfine transitions must change as well, to make the defined second longer or 
shorter. So, in these examples the elevation does not change the time, but the 
way the atoms behave. What obvious item am I missing, besides maybe brain 
capacity? Thanks - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Shoppa
Sent: Friday, November 27, 2015 9:19 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Einstein Special on PBS

Would've been more fun to see Tom and his kids going to the top of Mt Ranier in 
2005 with the ensemble :-). http://leapsecond.com/great2005/

They mentioned some "6 miles per day" offset due to GPS relativity effects.
I think this is the sum of both special relativity (time dilation) and general 
relativity (gravitational) effects. The GR correction is 45 microseconds a day 
fast; the SR correction is 7 microseconds slow. 38 microseconds seconds is 11 
kilometers which is indeed 6 or 7 miles. While time drifts 38 microseconds a 
day, I'm not sure that GPS coordinates would drift that fast - aren't most of 
the corrections in the same direction?

Seeing Kip Thorne describe black holes was a blast - he refused to use the word 
mass when describing them, just like when I took a course from him in 1990. 
When my advisor taught the same course, I pleaded with him, "please use 
coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my 
brain does not work that way!!! I would've failed the course if it was only GR; 
fortunately it also had plasma physics in the same quarter, and I was an ace at 
that due to some undergraduate work.)

Tim N3QE

On Fri, Nov 27, 2015 at 12:05 AM, Arthur Dent 
wrote:

> In the special it looks like they used two HP5071A standards, an
> SRS620 counter, and a scope. They first made sure the stds were in 
> sync then took one to the building at the top of the ski lift on New 
> Hampshire's Mount Sunapee at 2726' elevation for 4 days where it would 
> be running a little faster because it would be slightly further from 
> the center of the spinning earth. After bringing the 5071A back from 
> the top of the mountain they checked the difference in the start of 
> square waves displayed on the scope and detected the 5071A at altitude 
> was now 20ns ahead of the 5071A kept at sea level, as predicted, if I 
> understood everything correctly. They explained that the clocks in the 
> GPS satellites traveling at a much higher speed had to correct for the 
> speed difference which also verified Einstein's theory.
>
> My wife and I were on the top of Mt. Sunapee this summer where we 
> enjoyed the views but didn't run any experiments. ;-)
>
> -Arthur
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> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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Re: [time-nuts] Einstein Special on PBS

[Mike Feher]

Hi Tom -

It has been a while. Well, I guess I am not in bad company if you struggled 
with this as well. I also like your take on it and will think some more, but it 
helped. So, if frequency remains the same, then d(phi)/d(t) ratio remains the 
same and both phase and time must change. Also, the concept that the number of 
transitions as a function of elevation (gravity) makes very good sense and of 
course would explain my dilemma. However, I am sure there is still something I 
am missing. Thanks & Regards - Mike  

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van Baak
Sent: Friday, November 27, 2015 1:18 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Einstein Special on PBS

Hi Mike,

It's a good question and I've wrestled with it too. I see two choices:
1) Time is stable and every ultra-precise timing measurement of atomic behavior 
appears to depend on gravity.
2) Every ultra-precise timing measurement of atomic behavior is stable, and 
Time appears to depend on gravity.

My impression is they are both equivalent and indistinguishable. Practical 
people like to use #1, for example, the SI second is defined as 9,192,631,770 
Hz specifically and only at mean sea level on planet earth; national 
laboratories, and some time nuts, correct their clocks for elevation. By 
contrast, astronomers and physicists use #2 because it make everything simpler 
and universal.

So you can say that a cesium clock ticks at 9,192,631,770 Hz +/- some function 
of gravity and velocity, or you can say that a cesium clock always ticks at 
9,192,631,770 Hz in its "own reference frame".

But either way, if you leave a clock on a mountain for a while, it comes back 
the same frequency it left. So what we measure is not the frequency, but the 
time (clock phase). The time the clock displays contains the sum total history 
of all frequency changes during the trip. You can't tell this during the trip, 
since the clock always thinks it is running at a constant and correct rate, 
wherever it is.

/tvb

- Original Message - 
From: "Mike Feher" <mfe...@eozinc.com>
To: "'Discussion of precise time and frequency measurement'" 
<time-nuts@febo.com>
Sent: Friday, November 27, 2015 7:37 AM
Subject: Re: [time-nuts] Einstein Special on PBS


>I just do not get it. I know that now I am 70 and my good smart days are 
>behind me, but, this should be simple. In all these clocks mentioned, time is 
>derived from the transition of a hyperfine line of a certain atom within some 
>element, in this case cesium, In order for any of these clocks to deviate in 
>relative time at different heights for example, it seems to me that the period 
>of the hyperfine transitions must change as well, to make the defined second 
>longer or shorter. So, in these examples the elevation does not change the 
>time, but the way the atoms behave. What obvious item am I missing, besides 
>maybe brain capacity? Thanks - Mike 
> 
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ, 07731
> 732-886-5960 office
> 908-902-3831 cell
> 
> 
> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Shoppa
> Sent: Friday, November 27, 2015 9:19 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] Einstein Special on PBS
> 
> Would've been more fun to see Tom and his kids going to the top of Mt Ranier 
> in 2005 with the ensemble :-). http://leapsecond.com/great2005/
> 
> They mentioned some "6 miles per day" offset due to GPS relativity effects.
> I think this is the sum of both special relativity (time dilation) and 
> general relativity (gravitational) effects. The GR correction is 45 
> microseconds a day fast; the SR correction is 7 microseconds slow. 38 
> microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While 
> time drifts 38 microseconds a day, I'm not sure that GPS coordinates would 
> drift that fast - aren't most of the corrections in the same direction?
> 
> Seeing Kip Thorne describe black holes was a blast - he refused to use the 
> word mass when describing them, just like when I took a course from him in 
> 1990. When my advisor taught the same course, I pleaded with him, "please use 
> coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my 
> brain does not work that way!!! I would've failed the course if it was only 
> GR; fortunately it also had plasma physics in the same quarter, and I was an 
> ace at that due to some undergraduate work.)
> 
> Tim N3QE
> 
> On Fri, Nov 27, 2015 at 12:05 AM, Arthur Dent <golgarfrinc...@gmail.com>
> wrote:
>

Re: [time-nuts] 10811 unsoldered fuse

[Mike Feher]

As I recall, the thermal fuse in the 10811 is not soldered in but it is
socketed. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Dimitri.p
Sent: Monday, October 19, 2015 3:32 PM
To: time-nuts@febo.com
Subject: [time-nuts] 10811 unsoldered fuse

How common is it to find undetected missing solder on 10811 parts after all
these years?

Dimitri

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Re: [time-nuts] Digital Phasae Lock Loops

[Mike Feher]

Hi Alex -

Someplace I have a copy of Floyd's pre-published manuscript for his first book. 
I use to used it a lot in the late 60's and early 70's till I actually got his 
published version. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Alexander 
Pummer
Sent: Friday, October 16, 2015 6:33 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Digital Phasae Lock Loops

actually my old friend Dr. Floyd Gardner -- who is the pope of the phase locked 
loops -- told me some thirty years ego , that the Best book os a very good 
introduction
73
Alex

On 10/16/2015 1:42 PM, Dave Daniel wrote:
> Roland Best's text is the best (no pun intended) one I have seen on 
> PLLs. I didn't know it was up to a sixth edition.
>
> On 10/16/2015 11:18 AM, Alexander Pummer wrote:
>> Hi Steve,
>> I will tell you a big secret; a digital PLL is not a low phase noise 
>> system and a very good introduction to PLLs and the digital PLL could 
>> be found in Roland Bests:
>>
>>
>>  Phase Locked Loops 6/e: Design, Simulation, and Applications
>>
>> 73
>> KJ6UHN
>> Alex
>>
>>
>> On 10/16/2015 7:45 AM, Martyn Smith wrote:
>>> Hello,
>>>
>>> I want to design a digital phase lock loop.
>>>
>>> I intend to lock a 10 MHz ultra low noise oscillator that we make to 
>>> an external frequency standard.
>>>
>>> I need a digital PLL as I’m trying to get a loop bandwidth < 0.1 Hz.
>>>
>>> Has anyone had any experience of Digital PLL’s or can point me to 
>>> any documents published?
>>>
>>> Regards
>>>
>>> Steve
>>> ___
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>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> and follow the instructions there.
>>
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>
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Re: [time-nuts] Chinese GPSDO 10 MHz error

[Mike Feher]

Look in the manual for the 8640B as they use FLL there when the lock button is 
pushed on the front panel. Simply, in one case, in lock, the numbers driving 
the frequency readout is saved and then when the oscillator drifts one way or 
the other, an EFC is applied that attempts to make the new readout driver 
number equal to the saved number. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Benward
Sent: Wednesday, August 26, 2015 11:55 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] Chinese GPSDO 10 MHz error

So how does a frequency lock work?  How is it implemented? Can someone sketch a 
schematic?

And what equipment or technique is used to measure a 2hz error at 100GHz?

Bob

 -Original Message-
 From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim 
 Shoppa
 Sent: Wednesday, August 26, 2015 5:18 PM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] Chinese GPSDO 10 MHz error
 
 Full KE5FX evaluation of BG7TBL GPSDO here:
 http://www.ke5fx.com/gpscomp.htm
 
 I'm wondering out loud if it might, like many hobbyist GPSDO's, be 
 frequency-locked rather than phase-locked and thus susceptible to 
 last-digit- counter bobble in some long-averaging counter.
 
 Tim N3QE
 
 On Wed, Aug 26, 2015 at 3:18 PM, Perry Sandeen via time-nuts  time- 
 n...@febo.com wrote:
 
  Hi,
 
 
 
  On the EEVBLOG  (http://www.eevblog.com/forum/index.php)
 
 
 
  They mention that the 2014-11-06version GPSDO that was “most 
  extensively tested, so far (by ke5x and others).
 
 
 
  (Has a) known bug, outputfrequency is not exactly 10mhz
  (9,999,999.999,800 Hz). This translates to ~2hzerror at 100ghz.”
 
 
 
  A question is if this bug isjust for this particular model or all 
  other versions suspect?
 
 
 
  I realize that in and of itsself it is very small error, but 
  errors tend to multiply or cause incorrectconclusions to testing.
 
 
 
  Another question is will the LHdisplay unit they offer work with 
  other Trimble units such as are offered byRDR?
 
 
 
  That said, these models seem tobe a very nice turn-key systems.
 
 
 
  Regards,
 
 
 
  Perrier
 
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and follow the instructions there.

Re: [time-nuts] 5 x 2 x 3 = 30 MHz

[Mike Feher]

I usually prefer to design Elliptic/Cauer filters and then adjust the cut-off 
frequency such that some of the zero's line up with whatever I want to really 
attenuate. - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp
Sent: Sunday, July 19, 2015 8:17 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5 x 2 x 3 = 30 MHz

Hi

There are an enormous number of variations on the basic SC trap. Most of what 
drives one to be “best” is the component selection process. If a coil above X 
uh simply will not fit, time for a new circuit ….

Bob

here.

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Re: [time-nuts] how to find low noise transistors

[Mike Feher]

But they can be found very inexpensively on eBay. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of John Miles
Sent: Saturday, July 18, 2015 11:00 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] how to find low noise transistors


 -Original Message-
 From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of 
 KA2WEU--
 - via time-nuts
 Sent: Saturday, July 18, 2015 3:40 PM
 To: time-nuts@febo.com
 Cc: akpod...@synergymwave.com; alexander.r...@rohde-schwarz.com
 Subject: Re: [time-nuts] how to find low noise transistors
 
 BFG540
 
 

That's what I mean -- both BFG540 and BFG591 have been discontinued by NXP.  
Guess they don't sell enough of them these days.

-- john, KE5FX
Miles Design LLC


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Re: [time-nuts] z3801a - serial help and for sale

[Mike Feher]

I modified one of my 3801s by placing a home brew linear power supply in it and 
a regular 3 connector AC plug in place of the 48 volt one. The power supply 
with the transformers was a tight fit, but I managed. It has been working fine 
for about 12 years. I also replaced the solid top cover with a fine mesh copper 
cover to get rid of the extra heat. Regards - Mike . 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of David Andersen
Sent: Thursday, June 11, 2015 4:39 PM
To: time-nuts@febo.com
Subject: Re: [time-nuts] z3801a - serial help and for sale

Thanks for the suggestions!

It turns out the answer was my serial dongle was failing.

*head bonk*  I swapped it out for another FDTI-based dongle and suddenly 
there's a happy working z3801a.

Before I throw it on eBay, would anyone like a working (yay!) z3801a modified 
to take mains power?  I'll throw in a little puck antenna and a homebrewed 
rs232 db25-to-db9 cable.  Pictures as per my previous email about it.

(please CC: me on reply -- I'm stuck in digest subscription and having
issues.)  ((No 'issues' jokes, please. :))

I'll note there's a risk that putting the switcher in it causes added noise.  I 
haven't measured it precisely enough to tell.  I didn't need nanoseconds for 
what I was using it for, but I did want it to be pain-free to plug in and use.

 -Dave


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Re: [time-nuts] Thunderbolt power connector crimper

[Mike Feher]

I forget the size of the pins on the Thunderbolt, but, I bought a crimper tool 
for Molex pins a while ago for a rather good price and really like it. This 
will crimp multiple gauge Molex pins and as I mentioned is very reasonably 
priced.. Shipping to Oz is another matter :).. 73 - Mike

http://www.powerwerx.com/search.asp?q=ct-oem 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Matt Robert
Sent: Monday, June 08, 2015 6:29 AM
To: time-nuts@febo.com
Subject: [time-nuts] Thunderbolt power connector crimper

Hi Guys,

I am currently in the process of completing my Thunderbolt project and I need 
to find a suitable crimper to attach wires to the pins that go inside the power 
connector.

The only reference I can find is on this page here (
http://www.prc68.com/I/ThunderBolt.shtml) that talks about the official Molex 
tool which is scarily expensive, and the page also mentioned a Radioshack tool 
that I can't find any further details on.

Can someone please point me in the right direction of a suitable crimper for 
the Molex 538-16-02-0103 pins.

Cheers,
Matt
VK2LK
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Re: [time-nuts] lawnmower robots may be the end of VLF timekeeping

[Mike Feher]

I remember that. It was when National was too cheap to cut their lawn. Regards 
- Mike 
 
Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Alexander 
Pummer
Sent: Saturday, May 09, 2015 9:13 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] lawnmower robots may be the end of VLF timekeeping

Bob Widlar -- yes the designer of the 741 -- of National Semiconductor had a 
better idea, he bought a few sheep
73
KJ6UHN Alex

On 5/9/2015 2:02 PM, Mark Sims wrote:
 iRobot (the Roomba vacuum cleaner people) have applied for an exemption to 
 allow them to send beacon signals in a 6-7 GHz band to fence in their new 
 lawnmower.  The band they want to operate in is apparently for indoor only 
 low power applications.

 The easy solution is to just buy some goats...  the emit very little in the 
 way of EMI...  but do emit other,  u,  signals.

 --
 Clearly, you need a better nav system for the robot based on precision 
 time of flight measurements from a network of transmitters around the
 property linked to your hydrogen maser.   
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Re: [time-nuts] Austron 1250A

[Mike Feher]

Yes. I had the same issue with several of my 1250s. Unless you intend to use it 
through a power outage, just disconnect the batteries and all should be fine. 
It will also be a lot lighter if you take them out. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Ole Petter 
Ronningen
Sent: Wednesday, February 18, 2015 12:47 PM
To: time-nuts@febo.com
Subject: [time-nuts] Austron 1250A

Hello

On a whim I purchased an Austron 1250A off of eBay, tested for power on only. 
I somehow doubt they told the whole truth there, as the unit makes a
*very* noticable buzzing sound when powered on!

The sound comes from a relay on the regulator board, oscillating wildly. I have 
a hunch that this might be because the NiCad batteries are stone dead.
Has anyone experienced this relay going nuts?`

Also, the manual gives clear warning not to operate the unit with the battery 
pack removed, but gives no reason.. Does anyone know why this might be a bad 
thing?

Thank you!
OleP
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Re: [time-nuts] Wavecres SIA-3000 and DTS-2070 schematics (was: T.I. questions)

[Mike Feher]

I have two DTS2070s. The only manual I can find now is one for the DTS-2079. No 
schematics, but, a whole lot of other info. Can email it to you if you would 
like. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Attila Kinali
Sent: Monday, February 09, 2015 5:28 AM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] Wavecres SIA-3000 and DTS-2070 schematics (was: T.I. 
questions)

On Fri, 06 Feb 2015 20:55:56 +0100
Magnus Danielson mag...@rubidium.dyndns.org wrote:

 The Wavecres SIA-3000 has a single-shot resolution of 200 fs, but the 
 trigger jitter. Later models only went to 300 fs as far as I know. The 
 DTS-2070C has a resolution of 800 fs.

Hmm... does anyone have the schematics (or any other description of the inner 
working) of those two? My google skills fail me.

Attila Kinali

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Re: [time-nuts] Phase Noise vs. AM noise

[Mike Feher]

Bob -

I am maybe using the wrong word discernible. By that I mean that you cannot 
discern phase noise from AM noise at the real low levels. You can certainly 
measure, or see the contribution of the total noise power, but do not 
necessarily know if it is phase noise or AM noise or how much of each is 
included. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp
Sent: Thursday, January 15, 2015 7:48 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Current state of optical clocks and the definition of 
the second

Hi

I guess the question becomes how low is low. 

If it’s a 50 ohm system 

If the power level is rational

If you are at room temperature 

There are some limits on how low low can be. 

You have a -174 dbm  / Hz thermal floor. AM or PM noise can only be 3db better 
than the thermal floor. At a power level of 1 watt, that’s a -204 dbc / Hz 
limit. You will spend some time correlating to that level. You also may need to 
play a bit with the input circuits to handle the 1W without damage. At a 
somewhat more common 100 mw, the limit is -194. People have been measuring 
phase noise in the  -190 dbc / Hz range for at least 20 years now. Correlation 
may take a week at some offsets. Time will be longer or shorter at other 
offsets. As with anything else, the more money (correlation channels)  you 
throw at the problem, the quicker it will go.  Numbers in the -180 vicinity 
with normal gear, offsets, and FFT windows are an overnight run sort of thing. 


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Re: [time-nuts] Current state of optical clocks and the definition of the second

[Mike Feher]

Hi -

I agree with what you stated, however, I am not sure that at real low levels 
they are actually discernible. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp
Sent: Wednesday, January 14, 2015 6:14 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Current state of optical clocks and the definition of 
the second

Hi

More or less by definition:

AM noise has the sidebands in phase, PM noise has the sidebands out of phase. 
PM adds to no envelope power, AM adds to the envelope power. If you have purely 
random noise, half of the power is AM, half is PM by this approach. If you have 
what is effectively a SDR (high speed ADC(s), decimators, cross correlation …) 
doing your phase noise measurement, figuring out sidebands and phase is part of 
the process. With an old style single mixer approach, you switch your operating 
point on the mixer.

Bob


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Re: [time-nuts] Current state of optical clocks and the definition of the second

[Mike Feher]

Bob -

What I am saying is, even at the levels you mentioned, what is measured is I 
believe the combination of phase and AM. In other words, you are just measuring 
noise, but, are not certain if it is all phase, or phase plus some AM. At least 
that is my recollection when I was heavily involved in it some 30 years ago. 
Thanks - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp
Sent: Thursday, January 15, 2015 7:48 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Current state of optical clocks and the definition of 
the second

Hi

I guess the question becomes how low is low. 

If it’s a 50 ohm system 

If the power level is rational

If you are at room temperature 

There are some limits on how low low can be. 

You have a -174 dbm  / Hz thermal floor. AM or PM noise can only be 3db better 
than the thermal floor. At a power level of 1 watt, that’s a -204 dbc / Hz 
limit. You will spend some time correlating to that level. You also may need to 
play a bit with the input circuits to handle the 1W without damage. At a 
somewhat more common 100 mw, the limit is -194. People have been measuring 
phase noise in the  -190 dbc / Hz range for at least 20 years now. Correlation 
may take a week at some offsets. Time will be longer or shorter at other 
offsets. As with anything else, the more money (correlation channels)  you 
throw at the problem, the quicker it will go.  Numbers in the -180 vicinity 
with normal gear, offsets, and FFT windows are an overnight run sort of thing. 

Bob
 

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Re: [time-nuts] Current state of optical clocks and the definition of the second

[Mike Feher]

At those low levels, how does one differentiate between phase or AM noise? 
Thanks  Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bruce Griffiths
Sent: Wednesday, January 14, 2015 1:22 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Current state of optical clocks and the definition of 
the second

Although the phase noise when using optical combs to generate Rf signals is low 
there is no mention of the am noise.

Bruce

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Re: [time-nuts] ks... answers The emails are getting long

[Mike Feher]

Hi Doug -

Wow. Wonder how many on here remember or know about National's Damn Fast 
line, HI. I used them all the time, and, still have a few. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Doug Ronald
Sent: Tuesday, November 18, 2014 6:21 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] ks... answers The emails are getting long
Importance: Low

I doubled my Austron 1250A from 5 MHz to 10 MHz with 2 NPNs fed in push-pull 
and output in parallel with a tuned circuit. Before buffering it with an 
LH0063, I fed the signal through a 10 MHz crystal, purchased at a local surplus 
electronics store for $0.95. The 2nd harmonic is about 70 dB down.

-Doug, AE6SY

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp
Sent: Tuesday, November 18, 2014 3:11 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] ks... answers The emails are getting long

HI

Actually there are three different approaches to the “double 5 MHz” question. 

Roughly 99.99% of all doubler / tripler OCXO’s out there do the trick with a 
simple single transistor stage and a  tuned tank. Follow it up with a tuned 
single transistor output amp. Cheap, easy, not very fancy, gets people mad when 
mentioned. It works plenty good enough. The basic design approach dates back to 
tube based multipliers done in the 1920’s. Just about any transmitter design 
textbook from 1930 through 1960 has design charts and tube based examples.  

Bob

 On Nov 18, 2014, at 4:26 PM, paul swed paulsw...@gmail.com wrote:
 
 Don
 The two units work together by a buggy cable from what I have heard so far.
 The Ref0 is the master that drives stuff it connects to REF1 that 
 disciplines REF0.
 If GPS goes away or the ref1 it all keeps ticking. This is been teh 
 system design for about 20 years.
 
 Many of us have the ref1 only and the internal osc is 5 Mhz so thats 
 why you have seen discussions on multipliers here. Tap the 5 Mhz 
 double it filter it and buffer it. there seem to be 2 schools of 
 thoughts on the process. Balanced mixer or Wenzel.
 I would have hacked the answer already. But I need to keep my ref1 
 running so that it ages in. ASI will refund your money if bad. But only in 30 
 days.
 I do like what I see from the KS-... Can never remember the number.
 Regards
 Paul
 WB8TSL
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Re: [time-nuts] Division Circuit

[Mike Feher]

Brooke -

You must have meant the 923. The 723 is a voltage regulator. I also used to 
have fun with the 900 series RTL stuff in the mid 60's. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Brooke Clarke
Sent: Friday, November 14, 2014 6:10 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Division Circuit

Hi:

The Twisted Johnson Ring Counter may be the one your looking for.
The individual stages are not clocked at the input frequency, but rather 
something like N/5.
http://en.wikipedia.org/wiki/Ring_counter#Four-bit_ring_counter_sequences
It's decodes using 2-input gates.
The last one I made used the 723 F-F from Fairchild.
http://www.prc68.com/I/comp.shtml#Lamp

Mail_Attachment --
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
http://www.prc68.com/I/DietNutrition.html
Tim Shoppa wrote:
 Yes! I did find a patent that illustrated the exact same feedback 
 circuit as in the EE times article. But most self-decoding ring 
 counters in mass-produced applications use simpler lower 
 propagation-delay gate arrangements to ensure the counter self-corrects any 
 defective sequences.
 e.g. look at how the CD4017 does not use a 10 input NAND gate!!!

 Tim N3QE

 On Fri, Nov 14, 2014 at 4:39 PM, Said Jackson via time-nuts  
 time-nuts@febo.com wrote:

 The premise of higher than normal click speed is false in the 
 article too because the complex NOR gate is slow with that many 
 inputs, and its tpd needs to be added to the Tsu and Tco of the flip 
 flop chains, as well as the pcb propagation delays through the worst case 
 trace..

 It would have been faster to simply use a single reset RC delay to 
 reset all FF asynchronously while only setting one FF at the same 
 time during power-on. That would remove the Nor gate delay from the 
 max speed calculation..

 Sent From iPhone

 On Nov 14, 2014, at 12:13, Don Latham d...@montana.com wrote:

 Thanks. You reminded me of the time when design ideas really had
 content. No
 more, I'm afraid...
 Don

 Azelio Boriani
 No need to digitize, the article is available here:
 
 http://www.edn.com/design/test-and-measurement/4347165/Circuit-divide
 s-frequency-by-N-1
 or here (in .PDF):
 ftp://ztchs.p.lodz.pl/PRP/PRP_2006_2007/71102di.pdf

 On Fri, Nov 14, 2014 at 8:02 AM, Perry Sandeen via time-nuts 
 time-nuts@febo.com wrote:
 List,



 I’ve digitized and edited an article titled* Circuit 
 DividesFrequency
 by N+1
 by Bert Erickson, Fayetteville, NY from EDN 7/11/2002*.



 Essentially, this circuit is expandable and allows for adivision 
 by any number plus one.



 Anyone who wants a PDF copy please send me an original emailoff list.



 Regards,



 Perrier


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 --
 The power of accurate observation is commonly called cynicism by 
 those
 who
 have not got it.
 -George Bernard Shaw

 Dr. Don Latham AJ7LL
 Six Mile Systems LLC
 17850 Six Mile Road
 Huson, MT, 59846
 mail:  POBox 404
 Frenchtown MT 59834-0404
 VOX 406-626-4304
 Skype: buffler2
 www.lightningforensics.com
 www.sixmilesystems.com


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Re: [time-nuts] NPR Story I heard this morning

[Mike Feher]

OK, I am going to show my ignorance now. Being in my 70th year, I forgot an 
awful lot of what I learned in school. 

Anyway, regarding time and gravity, I certainly believe the mathematics of 
Einstein and others, however, I have a hard time believing that man-made 
instruments to measure the effects of gravity on time is valid. For example in 
a Cesium clock, time is a function of the transition time between two hyperfine 
lines of Cesium atoms. So, does gravity affect this transition time within the 
Cesium atoms? It may very well, but, I am not smart enough to know that. Maybe 
someone can help.

Also, when someone mentioned moving a very sensitive scale up in elevation and 
noting the difference due to gravitational effects, also seems odd to me. Seems 
like even in the most sensitive scales, weight is measured as the difference 
between the weighing platform and the body of the instrument. Here again, 
moving the whole assembly up in elevation it would seem to me that gravity 
would affect both the platform and the body, and the relative weight indicated 
should remain the same. What am I missing besides gray matter? Thanks - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van Baak
Sent: Monday, November 03, 2014 3:55 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] NPR Story I heard this morning

 Yes,  A story about time and frequency standards.  They actually used 
 numbers like 10E16 in the story.  Apparently at that level your clock 
 can measure a change in elevation of a few centimeters because of the 
 relativistic effects of the reduced gravity field in just a few cm.

Hi Chris,

That's correct. When it comes to frequency standards the official SI second is 
defined only for sea level. We know time and frequency are bent by speed or 
gravity; time is the integral of frequency; and frequency is a function of 
height (h) by approximately gh/c². It's that simple. But it's a very tiny 
effect.

Planet gravity fields decrease quadratically over large distances (1/R²) but 
approximately linearly near the surface. So here on Earth, with g = ~9.8 m/s² 
and c = ~300,000 km/s, frequency increases by about 1e-18/cm, or 1e-16/m, or 
1e-13/km. This is called gravitational time dilation, or blueshift.

Now, for amateurs like us who just make things at home or buy and repair atomic 
clocks on eBay, numbers like 1e-18 and 1e-16 are completely out of range: 
that's what government labs are for. But the 1e-13 number is interesting, and 
approachable -- especially if you live near a tall mountain.

If you take a 1e-14 stable cesium clock up 1 km, it will run fast by about 
1e-13 (in frequency) and thus it will gain about 10 ± 1 ns per day (in time, or 
phase) compared to a clock left down at home. These days, time differences at 
the nanosecond level are easily measurable -- so that's what I did with 
http://leapsecond.com/great2005/

Of course, NIST  USNO always have much better clocks than we do, so they can 
measure the effect of smaller elevation changes, over smaller time scales. Just 
amazing. Maybe we'll be able to buy an optical clock on eBay 20 years from now.

Note that their clocks are not (yet) portable and consequently you can make a 
more accurate gravitational time dilation / general relativity measurement at 
home by taking vintage hp 5071A cesium beam microwave clocks up a tall mountain 
than they can with record-setting strontium optical clocks inside a NIST 
building.

Essentially, if you take a clock to high altitude for a weekend you create a 
super-duper blueshift microscope. Instead of unimaginably small numbers like 
1e-18, I went up about 1340 meters (instead of just 1 cm) and I stayed up there 
about 42 hours (instead of one second). Thus my cm-second magnification 
factor was 1340 * 100 * 42 * 3600 = 20 billion! That reduces a crazy tiny 
number like 1e-18 to a real, tangible, measurable, fun-with-family, DIY time 
dilation number like 2e-8, or 20 ns.

/tvb

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Re: [time-nuts] Sun Outage

[Mike Feher]

Bob -

I do not believe it has any effect. The DirecTV satellites are geostationary at 
about 22K miles. I used to experience the same phenomenon in the late 70's with 
my TVRO receiver at C band. GPS has some 36 or so satellites in a Medium Earth 
Orbit (MEO). Blockage, if it can even occur due to the nature of the receiving 
antenna, of a single one for a few minutes will have no discernible effect in 
my opinion. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Stewart
Sent: Thursday, October 09, 2014 1:40 PM
To: Time Nuts
Subject: [time-nuts] Sun Outage

Two days this week, there was a 3 or 4 minute outage on DirecTV as the sun 
aligned with the satellite and my dish.  So I was wondering what kind of effect 
this has on the GPS system and especially timing receivers.


Bob - AE6RV
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Re: [time-nuts] Clock level conversion 5V - 3.3V

[Mike Feher]

About 8 or 9 years ago my HP active 2 way GPS smart splitter died. After taking 
off the cover, and some troubleshooting, I found that the 5 volt to 3.3 volt 
regulator was open. Since it was an SMD device, and I did not have a 
replacement, I just cut the device out, and, using a small piece of wire 
connected the 5 volts to where the 3.3 volts from the regulator was going. It 
is still working fine today and has been on continuously. So, in my case at 
least, in this one sample case, the 5 volts did not damage the 3.3 volt 
amplifiers in the splitter. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 (B)
908-902-3831 (C)


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Andy
Sent: Wednesday, October 01, 2014 3:50 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Clock level conversion 5V - 3.3V

If it were me, I'd avoid the active buffers since there is no need for them
when going from higher to lower voltage swings.  The output of a
buffer/inverter is guaranteed to be at least a little less clean than what
you started with.

First, check to see if the 5V output really is a 5V signal.  If it's TTL,
it might swing only to about 3.5V anyway.  (Connecting a weak load to
ground can make this more pronounced.)  Check to see if your 3.3V part's
input tolerates 5V signals.  The chances may be small, but it might just be
that you can go direct with absolutely nothing in between.

You could use a resistive divider at the destination device that serves two
purposes: both attenuating the signal, and terminating it.  In which case
it's a win-win.

If need be, the resistive divider can add a small DC offset, say if you
need to drive 1.8V logic and the OCXO's Vol isn't low enough.

Instead of a resistive divider, you might use a schottky switching diode to
limit the positive swing.  Then you get close to a replica of the OCXO's
signal through the switching range of the input pin, with attenuation
kicking in only when the voltage starts going too high.

I don't know if these devices are still popular, but there are passive FET
signal 'limiters' that work in a similar way; the signal passes through
unchanged until the instantaneous voltage reaches 3V or so, and then the
FET eases off and doesn't pass higher voltages.  Some years ago they were
popular for making 5V/3.3V signal transitions.  They are supposed to have
negligible delay (well, you know) when the FET is on, they are
bidirectional (not that it matters to you here), and they consume no
power.  I think the name Quickswitch was one of the brand names, and
Pericom and IDT were two of the manufacturers.

Regards,
Andy
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Re: [time-nuts] 10811 Thermal fuse?

[Mike Feher]

I would just put in a piece of wire. They mostly only fail due to age. The wax 
inside the fuse loosens up over time and then, eventualy, the two meatal strips 
open up. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Rae
Sent: Tuesday, September 02, 2014 3:24 PM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] 10811 Thermal fuse?

I'm sure this has been discussed to death before, but does anyone know of a 
source of thermal fuses small enough to fit in the -hp- 10811?  I have found 
plenty of larger ones, none of which will fit and would rather not just link it 
out.

Dan
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Re: [time-nuts] 10811 Thermal fuse?

[Mike Feher]

This type of cutout fuse can never re-connect. It is a very clever design where 
there are two metal strips in contact with each other that have springiness to 
them, so, they would normally not be in contact. During assembly, the fuse 
cavity is filled with a waxy material, consistency dependent on temperature 
cut-out requirements. As the critical temperature is reached, the wax melts, 
and, the two springy steel contacts separate. Of course then the unit cools 
down, the wax hardens, and the contacts stay separated. As I said in a previous 
post, these fuses tend to age and eventually open up even in a well performing 
circuit. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Dave Daniel
Sent: Tuesday, September 02, 2014 8:05 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 10811 Thermal fuse?

I believe a thermal cut-out is a device which interrupts the circuit when a 
prescribed temperature is reached or exceeded (in some cases by heating from an 
increase in current through a conductor), but which re-connects the circuit 
once the temperature has dropped below the cut-out temperature (possibly with 
some hysteresis built in). A fuse, on the other hand, interrupts the circuit 
after a certain current threshold is exceeded (and, of course there is an 
increase in temperature related to the increase in current) but which is 
destroyed in the process out interrupting the circuit.

DaveD


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Re: [time-nuts] VLF Phase-tracking receivers.

[Mike Feher]

Unless on what you were working on it had a different meaning, MSK means
Minimal Shift Keying. It is still a PSK modulation of any order, however
the transition between significant phase locations is not instantaneous,
but, shaped in various ways to smooth the transition. This results in a
waveform that has a minimal AM component which then consequently reduces
spectral regrowth when amplified by a non-linear amplifier. Allows for
closer channel spacing, and is generally nicer, at the expense of additional
complexity. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Kenneth G. Gordon
Sent: Sunday, August 10, 2014 12:27 PM
To: paul swed; time-nuts@febo.com
Subject: Re: [time-nuts] VLF Phase-tracking receivers.

On 10 Aug 2014 at 6:24, paul swed wrote:

Hello again, Paul. Thanks for replying. Please see below.

 On iPhone
 Yes but those stations are fsk so the offsets an issue.

As I understand it from back in the 1970s when I was first working on this
sort of thing, the modulation is not FSK, but MSK (whatever that is) at
something like 25 to 50 Hz, and the Navy installed the necessary equipment
in the 1970 time-frame to assure that the transmitted signals are
phase-stable. The same thing, apparently holds true for GBR and some of the
other stations like those. Russian, for instance.

I have no idea what, exactly, has occurred in this area since then though.

 We may assume the transmitter is accurate.

Yes.

 But how accurate?

That is a good question. I have no idea at this point. I'll try to find out.

 Then the fsk generator

Well, as I said above, it is not FSKexactly...

I DO know that the Navy had problems when they first tried FSK with their
antenna tuning methods. Due to the extremely hi Q of their antenna
systems, any useable frequency shift (at the receiver) was so great that it
pretty much threw their antennas out of tune on either mark or space. Thus,
they had to use a different method. I never did learn what that method was. 
Perhaps now is the time for me to find out.

Thanks again,

Ken W7EKB
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Re: [time-nuts] OT Gel Cell question

[Mike Feher]

There are some YouTube videos showing how to rejuvenate. Also you can google
it for an explanation. I have wanted to try and rejuvenate some, even bought
the necessary ingredients, but never got around to it. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Robert Roehrig
Sent: Sunday, July 27, 2014 12:52 PM
To: time-nuts@febo.com
Subject: [time-nuts] OT Gel Cell question

Anyone know why Gel Cell batteries go HI-Z if discharged below a certain
level?
Also is there a way to rejuvenate a dead one?
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Re: [time-nuts] Synergy-GPS SSR-6tru Problem Resolved

[Mike Feher]

I knew Ulrich and talked to him a few times on 2 meters. Met him at a
conference also. I was under the impression that his wife was the one
running Synergy. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Alexander Pummer
Sent: Friday, July 25, 2014 8:52 PM
To: Bob Stewart; Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Synergy-GPS SSR-6tru Problem Resolved



Synergy's owner Ulrich Rohde N1UL --DJ2LR/DL1R is a long time ham radio
operator, and he will go pretty far to help for an other ham,
73
KJ6UHN ex DL...
Alex

On 7/25/2014 5:27 PM, Bob Stewart wrote:
 And while this subject is still up, I want to let the group know that
Synergy *really* went out of their way to help me with this.  I was a bit
surprised at their level of commitment to some ham radio operator who had
bought a single unit from them and probably didn't know what the heck he was
talking about.  A real class act all around!

 Bob - AE6RV



 
   From: Art Sepin a...@synergy-gps.com
 To: Bob Stewart b...@evoria.net; Discussion of precise time and 
 frequency measurement time-nuts@febo.com
 Cc: Tom Van Baak t...@leapsecond.com; Dusty Morris 
 doxielove...@cox.net
 Sent: Friday, July 25, 2014 5:17 PM
 Subject: RE: [time-nuts] Synergy-GPS SSR-6tru Problem Resolved
   

 Bob,

 Once in a while a mea culpa is required and we're posting it here so
everyone understands our commitment to the users of Synergy's products.

 The Original Synergy Adaptor Board was designed to allow Motorola's newer
3 volt 12 channel M12+ to plug into an older 5 volt 8 channel UT+ slot. That
product worked for hundreds of users over the years until (we found out
through your personal aggravation and agony) the recent introduction of
Synergy's SSR series of u-Blox based precision timing boards.

 To make sure that the Synergy UT+ Adaptor Board issue is put to bed
properly we asked for an external, formal technical review of this product
that was introduced fourteen years ago.

 The reviewing engineer's first comments were Ouch! This will not work.
And, no, the SSR boards do not work the same as the M12 boards on the
Synergy Adaptor Board. The M12+ and M12M receivers have separate serial
ports for the two functions (Receiver command RxD and DGPS RxD input) so it
does not matter what you do with the RTCM port, pin 5 on UT+ connector and
pin 8 on the M12+/M12M connector, if not in use with an M12x receiver.

 The SSR boards, however, had to combine the two serial data streams
expected by the M12x navigation receivers into one because the u-Blox
receiver modules only use one serial input port for both receiver commands
and DGPS correction data. The Synergy Adaptor Boards use a simple gate
combiner circuit that worked well when using the M12+ or M12M but left
Synergy open to this problem when using an SSR. Both serial lines on the SSR
board, pins 2 (Receiver RxD) and 8 (DGPS RxD) are pulled high on the SSR
board so open pins are OK but they must not be grounded.

 The solution is for Synergy to make a UT+ Adaptor Board part number
available to users who only want to test the features of SSR timing
receivers.

 That new SSR only Adaptor Board part number, which we'll have available in
a few days, will remove R3 (4.7K) and R4 (6.8K) from the adapter board and
the compatibility issue will be resolved. In the interim, other users can
pull pin 5 of the UT+ connector high (+5V) as you did.

 We apologize for the confusion and frustration, Bob, and thank you for the
valuable feedback!

 Art Sepin
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Re: [time-nuts] Can anybody use a Fluke 207-1 VLF Rcvr/Comp or Trak Time Code units? Plus, Free Stuff Aug. 1/2

[Mike Feher]

I'll second that about the nut part. The first time Tom and I had any
dealings was when he bought some nixies on eBay that I desperately needed.
Being a reasonable guy, he helped me out. BTW, I also have a very large
calculator collection. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Tom Van Baak
Sent: Saturday, July 05, 2014 5:12 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Can anybody use a Fluke 207-1 VLF Rcvr/Comp or Trak
Time Code units? Plus, Free Stuff Aug. 1/2

Hi Walter,

Thanks for the posting here on Time-Nuts and the advanced warning of your
annual event. I know those of us in the Pacific North West will consider the
car trip.

To fellow time-nuts -- Walter has been on the 'net for a very long time. See
his superb web site (http://sphere.bc.ca/). He and I share a fascination
with calculators, slide rules, and nixie tubes (both related to the
historical pursuit of precise time  frequency). I have no connection with
his company (never even met him), but I can spot a 'nut from anywhere.

/tvb

- Original Message - 
From: walter shawlee 2 walt...@sphere.bc.ca
To: time-nuts@febo.com
Sent: Saturday, July 05, 2014 12:44 PM
Subject: [time-nuts] Can anybody use a Fluke 207-1 VLF Rcvr/Comp or Trak
Time Code units? Plus, Free Stuff Aug. 1/2


I am trying to make some space in a very over-crowded storage area here.
 I have a very nice Fluke VLF receiver comparator, s/n 130 c/w chart
recorder, 
 but never got a chance to try it out, because we have no antenna.  if it's
worth 
 $50 to somebody, plus shipping, it can be yours.  l also have a huge range
of 
 Trak (and others) time code generators, receivers, code converters, etc.
email 
 if any interest, set up your own cape canaveral launch control room! Not
sure 
 why I ever bought them, but they can certainly be yours.
 
 Also Sphere is having its annual Free Stuff event this coming friday and 
 saturday (Aug 1+2),
 tons of free parts, test gear, Rf/microwave, electronic scrap, etc. Email
for 
 more details, or check the Tek and HP user groups on Yahoo. We have been
doing 
 this for over 10 years, people seem very pleased with what they get. yes,
we are 
 in Canada, but lots of people come up from washington and oregon, it's a
great 
 weekend excursion! We do take requests if we happen to have what you need.
 
 all the best,
 walter
 
 -- 
 Walter Shawlee 2, President
 Sphere Research Corporation
 3394 Sunnyside Rd.,  West Kelowna,  BC
 V1Z 2V4  CANADA  Phone: (250) 769-1834
 walt...@sphere.bc.ca
 WS2: We're all in one boat, no matter how it looks to you
 


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Re: [time-nuts] WWVB paper in May 2014 IEEE communications...

[Mike Feher]

Wonder what the consequences to my Junghans watch will be? - Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Tom Van Baak (lab)
Sent: Saturday, May 31, 2014 4:14 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] WWVB paper in May 2014 IEEE communications...

http://tf.boulder.nist.gov/general/pdf/2719.pdf

/tvb (i5s)

 On May 31, 2014, at 1:03 AM, David I. Emery d...@dieconsulting.com
wrote:
 
Well the actual details of the WWVB modulation and time codes are 
 now published.
 
Was just leafing through some journals while doing some boring 
 system configuration here...
 
IEEE Communications Magazine May 2014 has a paper on page 210 by 
 Yingsi Liang, Oren Eliezer, Dinesh Rajan, John Lowe
 
 WWVB Time Signal Broadcast Format and Multi Mode Receiver
 
Seems to tell a lot more... 

 --
  Dave Emery N1PRE/AE, d...@dieconsulting.com  DIE Consulting, Weston, 
 Mass 02493 An empty zombie mind with a forlorn barely readable 
 weatherbeaten 'For Rent' sign still vainly flapping outside on the 
 weed encrusted pole - in celebration of what could have been, but wasn't
and is not to be now either.
 
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Re: [time-nuts] 2014 Million £ Longitude Prize

[Mike Feher]

Decimal point Brooke, HI. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Brooke Clarke
Sent: Tuesday, May 20, 2014 4:01 PM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] 2014 Million £ Longitude Prize

Hi:

The UK in recognition of the 300th anniversity of the first Longitude Prize
is now working on another one.
http://www.longitudeprize.org/
A million pounds is about 16.8 million dollars.

--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html

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Re: [time-nuts] optically excite a quartz crystal?

[Mike Feher]

In my over 50 years of active ham radio experience as well as in my
professional one, I have literally taken apart 10s of thousands of crystals,
and, have never seen a single on where there has not been a physical contact
with the quartz. That of course includes the most common FT-243. Regards -
Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bob Camp
Sent: Sunday, April 20, 2014 9:06 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] optically excite a quartz crystal?

Hi

The WWII era FT-243 is one example of a crystal that has the active portion
of the electrodes separated from the resonator by an air gap. There are lots
of similar holders from that era that do pretty much the same thing.
Non-contacting electrodes are not very new.

Bob


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Re: [time-nuts] optically excite a quartz crystal?

[Mike Feher]

Agree there are some like that, but, only a few. A large spring loaded plate
is not going to dampen a piece of quartz vibrating in the MHz range at all.
Granted, the sealed, and metalized construction is a better one, but it is
mostly done to minimize shock and impurities. - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bob Camp
Sent: Monday, April 21, 2014 9:17 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] optically excite a quartz crystal?

Hi

If you look closely at most of them, the plates are not flat. They are
higher on the edges than in the center. There's a gap in the middle. If you
don't have the gap, the blank is constrained by the big heavy plate. That
damps the resonance and lowers the Q.

Bob

On Apr 21, 2014, at 9:00 AM, Chuck Harris cfhar...@erols.com wrote:

 I'm puzzling over this statement.  The FT-243's I have seen have a 
 spring that squishes the quartz blank between the electrodes.  They 
 aren't plated onto the quartz, but they are still in intimate 
 mechanical and electrical contact.
 
 -Chuck Harris
 
 Bob Camp wrote:
 Hi
 
 The WWII era FT-243 is one example of a crystal that has the active 
 portion of the electrodes separated from the resonator by an air gap. 
 There are lots of similar holders from that era that do pretty much 
 the same thing. Non-contacting electrodes are not very new.
 
 Bob
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Re: [time-nuts] Good use for an HP 10811

[Mike Feher]

It's alright - he just reciprocated :) - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Brian Lloyd
Sent: Monday, February 17, 2014 9:46 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Good use for an HP 10811

On Mon, Feb 17, 2014 at 8:31 AM, David J Taylor 
david-tay...@blueyonder.co.uk wrote:

 @uhf_satcom just tweeted:

 Finally, a signal from ESA Rosetta @ 755Million Km distance! Best DX 
 so far @uhf_satcom FFT; http://pjm.uhf-satcom.com/ 
 twtr/rosetta_8422496_170214.jpg ... - antenna 1.8M diameter

  https://twitter.com/uhf_satcom/statuses/435339066024808448

 Hope the link works!

 His receiver chain is synced to an HP 10811, allowing him to use 
 sub-Hz bandwidths to get that singal with just a 1.8 m dish.  Very well
done!

 (and apologies for it being frequency and not time!)


But it is! Time is just 1/f. Or is frequency 1/t? I can never remember which
is which. ;-)

--
Brian Lloyd, WB6RQN/J79BPL
706 Flightline Drive
Spring Branch, TX 78070
br...@lloyd.com
+1.916.877.5067
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Re: [time-nuts] Tom's Adventures of a Time Nut (Banquet Talk)

[Mike Feher]

Great video Tom. I forwarded it to some friends. 73 even if you are not a
ham :). - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Tom Van Baak
Sent: Thursday, January 30, 2014 7:05 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Tom's Adventures of a Time Nut (Banquet Talk)

I remember they recorded it. I just found out today it's on YouTube! Cool. I
guess. It's always weird to hear or see oneself speak, but if you watch it I
think it describes the time nut hobby pretty well.

If you want to follow the PowerPoint presentation instead of the long talk,
a copy if it is here:

http://leapsecond.com/dcc2013/

/tvb

- Original Message - 
From: Bob Stewart b...@evoria.net
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Sent: Thursday, January 30, 2014 11:11 AM
Subject: [time-nuts] Tom's Adventures of a Time Nut (Banquet Talk)


Today's SouthGateARC.org page has a link to Tom's talk at the 2013 TAPR/ARRL
Digital Communications Conference. I don't know whether this has been linked
to time nuts in the past, but it's an enjoyable presentation.

southgatearc.org/news/2014/january/adventures_of_a%20_time_nut.htm#.UuqiQ5Ui
wag

Bob - AE6RV


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Re: [time-nuts] Measuring TV delays

[Mike Feher]

Cable here had about a 10 second latency. HNY - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


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Re: [time-nuts] Man killed in quartz crystal accident

[Mike Feher]

John -

You are on the wrong group for this - 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of J. Forster
Sent: Tuesday, November 26, 2013 9:30 AM
To: Bill Dailey
Cc: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Man killed in quartz crystal accident

It's a matter of perception of risk.

Opponents of nuclear power have successfully propagandized risks out of all
proportion compared to other risks.

There are many more rational things to worry about, including a rogue state
or terror group acquiring CW, BW. And, CW and BW are much easier to make/get
than nuclear stuff. If you can brew beer, you can make crude BW agents.
Furthermore BW spreads by itself.

The world has not really seen a serious BW incident AFAIK, but antibiotic
resistant strains are rampant in US healthcare. A serious BW attack would
make those issues seem trivial.

Furthermore, nuclear materials can be detected pretty easily. AFAIK, there
are no readily available detectors for virii or bacteria.

Scientists do nobody any favors by overblowing some risks to fit their
political agenda.

-John

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Re: [time-nuts] The 5MHz Sweet Spot

[Mike Feher]

Exactly - I mentioned this on here about 3 years ago and all of the
self-proclaimed geniuses poo-pooded it.  I was told early in my engineering
career in the early 70's,  by a very smart man, when I thought I had all of
the answers, that considering all of the trade-offs regarding performance,
around 3 MHz for a crystal is best, operating in the 3rd overtone mode,
hence the slow progression from the 1 and 5 MHz standards to 10 MHz. Now,
getting close to 70, I just see what I can learn from all the smart people
on here, and keep quiet most of the time. Regards - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of David McGaw
Sent: Saturday, November 02, 2013 1:30 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] The 5MHz Sweet Spot

This all seems to be forgetting that the crystals are usually operated at
3rd or 5th harmonic.  The crystal in a 10811A is 10 MHz/3rd overtone.  A
high quality 5 MHz/5th overtone crystal is really a 1 MHz fundamental, a
large piece of quartz.  Running at a harmonic greatly reduces the influence
of the package.

David


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Re: [time-nuts] The 5MHz Sweet Spot

[Mike Feher]

Yes - me too - several even published books and papers on the subject.
Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bob Camp
Sent: Saturday, November 02, 2013 10:01 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] The 5MHz Sweet Spot

Hi

Well what I've been going from is the information I was taught by the people
who actually designed all those crystals back in the 40's 50's and 60's.

Bob

On Nov 2, 2013, at 9:50 AM, Mike Feher mfe...@eozinc.com wrote:

 Exactly - I mentioned this on here about 3 years ago and all of the 
 self-proclaimed geniuses poo-pooded it.  I was told early in my 
 engineering career in the early 70's,  by a very smart man, when I 
 thought I had all of the answers, that considering all of the 
 trade-offs regarding performance, around 3 MHz for a crystal is best, 
 operating in the 3rd overtone mode, hence the slow progression from 
 the 1 and 5 MHz standards to 10 MHz. Now, getting close to 70, I just 
 see what I can learn from all the smart people on here, and keep 
 quiet most of the time. Regards - Mike
 
 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell
 
 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] 
 On Behalf Of David McGaw
 Sent: Saturday, November 02, 2013 1:30 AM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] The 5MHz Sweet Spot
 
 This all seems to be forgetting that the crystals are usually operated 
 at 3rd or 5th harmonic.  The crystal in a 10811A is 10 MHz/3rd 
 overtone.  A high quality 5 MHz/5th overtone crystal is really a 1 MHz 
 fundamental, a large piece of quartz.  Running at a harmonic greatly 
 reduces the influence of the package.
 
 David
 
 
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Re: [time-nuts] Webinar: Phase Noise Jitter Measurements by Rohde Schwarz

[Mike Feher]

I use antbar, which is free, to save video files. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Dr. David Kirkby
Sent: Thursday, October 03, 2013 4:22 PM
To: Electronics and Books; Discussion of precise time and frequency
measurement
Subject: Re: [time-nuts] Webinar: Phase Noise  Jitter Measurements by Rohde
 Schwarz

I suspect there is software which will just capture whatever is on the
screen. Perhaps Google will find something.

It would seem a bit dumb for R+S to produce this, let 30 or so people look
at it, then not make it available to anyone else. That works out a lot of
money per person looking!!

I've never found the R+S site too useful for support, which is why I tend to
buy HP/Agilent and not R+S stuff. But maybe one could find out from R+S if
they intend to archive it.

Dave



On 3 October 2013 20:11, Electronics and Books
electronicsandbo...@yahoo.com wrote:
 I have tested the seminar this evening. Its a series of flash files with a
size of 20 - 50k. They can be saved in a hurry. I could not find a audio
file, its also one of the flash files. At the end all files are gone. Its
not very practical to save it.






 
  From: Dr. David Kirkby drkir...@gmail.com
 To: Discussion of precise time and frequency measurement 
 time-nuts@febo.com
 Sent: Thursday, October 3, 2013 9:35 AM
 Subject: Re: [time-nuts] Webinar: Phase Noise  Jitter Measurements by
Rohde Schwarz


 On 3 October 2013 02:26, Joseph Gray jg...@zianet.com wrote:
 I won't be available when this is live. Do you know if the video will 
 be available afterwards?

 Joe Gray
 W5JG

 Sorry, I don't know. You could ask either R+S or MWRF. I know Agilent 
 archive their webinars, but I've never seen one from R+S or WRRF 
 before, so I don't know if it will be archived.

 Typically these sort of things require one to enter a user name and 
 password to view, so it is not something you can record on your own 
 computer easily - if at all. It might be possible for someone else to 
 record it. I must admit I don't know what software one could use to do 
 it, but I suspect it must be technically, (though perhaps not 
 legally), possible to record it.


 Dave
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Re: [time-nuts] BVA Oscillaotrs

[Mike Feher]

Said -

I bet you he meant exactly what you said, just had a mistake in the
representation of the exponent. Hope all is well with you. Was just at GD
all week. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Said Jackson
Sent: Friday, August 30, 2013 11:53 AM
To: Discussion of precise time and frequency measurement
Cc: time-nuts@febo.com
Subject: Re: [time-nuts] BVA Oscillaotrs

Steve,

10E-013 means 1E-012. But the BVAs run in the low xE-013, about 10x better
than that. And they are specifically designed to give great ADEV from at
least 1s to 30s and more.

Agreed, its very easy to find fantastic phase noise performance from NEL,
Pascal, Wenzel and others. That (-180dBc noise floor etc) seems to be no big
deal these days, even though a very good Pascal ocxo will still cost as much
as four CSACs or more.

Please give some examples of oscillators that were designed specifically for
ADEV performance and can be ordered with specific ADEV parameters or are
known to have these kinds of performance levels typically, I don't know of
many.. Maybe 1 out of 10 HP 10811 will have ADEV in the low xE-013 as far as
I have seen. Tom Van Back has a nice treatise on the ADEV of a large number
of 10811's he measured in his Z38xx gpsdos, only some are truly great.

Thanks,
Said

Sent From iPhone

On Aug 30, 2013, at 8:21, Martyn Smith mar...@ptsyst.com wrote:

 Hello,
 
 Today many manufacturers are producing 10 MHz oscillators that offer 
 many advantages over BVA.
 
 Phase noise of   -116 dBc @ 1 Hz with a -175 dBc noise floor, ageing 
 of 5 x
 10E-9 per month and a G sensitivity of 5 x 10E-11 /g in all axis is 
 available on a new product.
 
 Also the short term Allan variance is in the low parts in 10E-13 for 
 one second.
 
 It seems to me the only real advantage of BVA is the long term ageing 
 and this can easily be sorted out by locking to a superior standard.
 
 Best Regards
 
 Steve
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Re: [time-nuts] 'nuther time related comic

[Mike Feher]

TVB probably drew that when he was in kindergarten :). - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Collins, Graham
Sent: Friday, August 23, 2013 9:19 AM
To: time-nuts@febo.com
Subject: [time-nuts] 'nuther time related comic


The time nut related comics that were posted the other day where good. I
made a note to start keeping track of those and similar ones.

And in today's funnies I found this one:
http://www.gocomics.com/herman/2013/08/21

Cheers, Graham ve3gtc



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Re: [time-nuts] ThunderBolt Display

[Mike Feher]

I sent an email to Andy from the web site and never heard back from him. -
Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Eric Garner
Sent: Thursday, August 15, 2013 1:22 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] ThunderBolt Display

Is anyone else having difficulty submitting a request for an order form?


On Wed, Aug 14, 2013 at 10:36 AM, Chris Albertson albertson.ch...@gmail.com
 wrote:

 What was the problem you found.  Other then a new to you platform?  
 I'm trying to understand why reading serial data would be hard.

 An advantage of the Adruino is that you don't need to make a PCB.  
 Even if you want to do something like add a graphical display or and 
 SD card for logging they just plug in, no solder required.

 Of course the pre-buillt display is even easier but can't be modified.

 One of my loner term goals is to move lady heather like functions onto 
 a small uP based device.  It seems wasteful to use a PC for this.


 On Wed, Aug 14, 2013 at 10:16 AM, Russ Ramirez russ.rami...@gmail.com
 wrote:

  Yeah, after trying to (reliably) get the time out of the pertinent 
  TSIP message using an Arduino UNO, I can understand your statement 
  Adam about the Arduino approach. It kinda works, but it felt like I 
  was fighting the implementation of the controller card and that I 
  should cut-over to my
 own
  solution using an Atmel, PIC or TI chip that I could just load C 
  code
 into.
  One of this lists members gave me the code I needed, so ironically 
  using the UNO made the project more difficult.
 
  Russ
  K0WFS
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 --

 Chris Albertson
 Redondo Beach, California
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-- 
--Eric
_
Eric Garner
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Re: [time-nuts] 9390-55108 IRIG

[Mike Feher]

That is exactly what I did about 7 or 8 years ago with one of my 9390's. I
have the 9390 in the lab and I bought a very large TRAK display which is in
my office. This 9390 has old firmware so the day of year number is wrong,
but the time is right as it is running off of GPS. I just have a long run of
coax between the two units. Regards - Mike  

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Rob Kimberley
Sent: Friday, August 09, 2013 1:58 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] 9390-55108 IRIG

It was originally designed to put on magnetic tape for time tagging
telemetry data from the White Sands missile testing base. It can be used for
a number of applications where you need to send time via coax cable to other
devices i.e. time displays, synchronising other timing devices.

Google IRIG-B and get the history.

Rob


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Re: [time-nuts] 5MHz x 10MHz

[Mike Feher]

It was my understanding that this sweet spot was optimum a little above 3
MHz, so, 3rd overtone crystals are used to generate a stable, low phase
noise 10 MHz.  Prior to that, 5 MHz was used and before that 1 MHz  Regards
- Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Tom Knox
Sent: Friday, August 02, 2013 2:02 PM
To: Time-Nuts
Subject: Re: [time-nuts] 5MHz x 10MHz

It is my understanding that Quartz has a sweet spot at 5MHz that makes it
ideal if the lowest possible phase noise and highest stability are needed.

Thomas Knox


 Date: Fri, 2 Aug 2013 19:57:16 +0200
 From: mag...@rubidium.dyndns.org
 To: time-nuts@febo.com
 Subject: Re: [time-nuts] 5MHz x 10MHz
 
 Hi Euclides,
 
 On 02/08/13 18:31, Euclides Chuma wrote:
  Hi,
 
  Why any equipments use 5 MHz and others use 10 MHz reference standard?
 
 There are some benefits (traditionally) in using 5 MHz over 10 MHz, 
 but
 10 MHz have become a common standard. The actual frequency isn't 
 really magic, but 5 MHz and multiples became somewhat standard in the 
 old MIL STD 188 for time-keeping, and it fit fairly well with what was 
 already in use. There are folks here that can correct me on massive
details.
 
 Today 10 MHz is more common because, well, engineers then to be 
 following habits, and 10 MHz sounds nice. I use 10 MHz mainly 
 because the application requires it, otherwise I use whatever 
 frequency fits my other needs, or what becomes easy to source.
 
 PS. Have not seen you post before, so welcome to time-nuts!
 
 Cheers,
 Magnus
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Re: [time-nuts] Lead acid battery noise levels

[Mike Feher]

A long time ago, when I was concerned about a phase noise issue, I found an
old NBS article. It was on measuring phase noise and included a schematic of
an ultra-low noise amplifier. In that amplifier they used Mercury batteries.
I also glanced at the referenced article, stating NiCad is the lowest noise,
and, NiCads were available for a long time, yet they used Mercury.  Regards
- Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of David Kirkby
Sent: Thursday, July 11, 2013 10:25 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Lead acid battery noise levels

On 11 July 2013 05:47, Mark Spencer mspencer12...@yahoo.ca wrote:
 Eric:

  http://tf.nist.gov/general/pdf/1133.pdf

 discusses the noise levels of various batteries.

 Regards
 Mark S


Sod's Law comes into play here. From a quick read of that, it seems NiCd are
best, but they are being phased out. I was told they were banned in Europe,
but I don't know if that is true. I'm pretty sure I've seen NiCd tools in
the local DIY store, so I doubt it is true.

Dave
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Re: [time-nuts] How dangerous if a Rb lamp broken?

[Mike Feher]

You must really be a legend in your own mind, and now, a self-proclaimed
time-nuts cop.  - 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Charles P. Steinmetz
Sent: Wednesday, July 10, 2013 1:59 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] How dangerous if a Rb lamp broken?

Perrier wrote:

You have absolutely NOTHING to fear. Here is why

Please keep your political comments to yourself and off the list (however
humorous you might think they are).  This is simply not the place for them.

Thank you,

Charles




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Re: [time-nuts] OT: eBay Contact Congress

[Mike Feher]

Well - I got it - and looking at the news confirms it. One news article did
mention that eBay was soliciting signatures for ammunition, so it would not
pass. It also looks like congress was only targeting businesses with sales
of over $1M/year. So, there is no rat, but regardless this junk does not
belong on here. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Richard Solomon
Sent: Tuesday, April 23, 2013 11:55 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] OT: eBay Contact Congress

I am a long time user of e-pay and did not get the message. So, I too, smell
a rat !!

73, Dick, W1KSZ


On 4/23/2013 7:22 AM, J. Forster wrote:
 I'm inclined to think it is genuine, but:

 As part of their security protocol, eBay tells you to check 'My Messages'
 by logging onto your account from the eBay home page.

 The 'Contact Congress' message is not in 'My Messages'.

 It concerns me that eBays message FAILS the authentication test they 
 themselves advocate. There may be a legal reason for this in the 
 corporate lobbying laws. I don't know.

 My concern has never been about the politics of the thing, but only 
 about whether it is genuine or fake.

 I am cautious, and within hours of the Boston Marathon Bombing, I was 
 getting spam/phishing/malware emails about it. It is certainly 
 possible that some miscreant is exploiting the news about eBay's 
 lobbying attempt the same way.

 YMMV,

 -John

 =






 Hi John,

 I also got one of these emails.  It appears to be genuine, especially 
 as two different sources directed to by Drudgereport, are talking 
 about a rush to pass Internet tax regulation during this week without 
 time for people to review the proposal and the White House pushing 
 the same point.

 No matter your view point about eBay, their concern is real and 
 should be of concern by everyone else.  Particularly, as it is being 
 handled to push it through so fast without the proper vetting.

 BillWB6BNQ


 J. Forster wrote:

 Hi,

 I recieved a very odd communication, apparently from eBay, this morning.
 It is a request to contact Congress about sales taxes on internet sales.

 It APPEARS to be genuine, but I'm unconvinced.

 Has anybody else received this email, and is it for real?

 Puzzled,

 -John

 

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Re: [time-nuts] Thermal noise contribution to phase noise

[Mike Feher]

I would think that you would not be able to tell the difference between AM
or PM noise. 73 - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bob Camp
Sent: Saturday, January 19, 2013 1:07 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Thermal noise contribution to phase noise

Hi

If:

1)  You have a carrier. Let's say it is an ideal signal with absolutely no
noise on it.
2) That carrier is in a real 50 ohm system

..there will be thermal noise at -174 dbm per Hz.

The model for a carrier includes both AM noise and PM noise. Correct?

The practical difference for small angle PM vs AM is the phasing of the
sidebands. Correct?

Either:

a) All of the noise is AM noise. 
b) All of the noise is PM noise.
c) Half of the noise power is AM and half of the power is PM.

Pick one, a,b, or c.

If you pick a or b, *why* and equally importantly *how* does all the random
thermal noise go only to one process? Since it's (by definition) random
(amplitude and phase), it's going to be tough to get it all in just one
bucket or the other. 

If the noise splits equally, then -177 is what you are going to get.

Bob

On Jan 18, 2013, at 11:52 PM, Joe Leikhim jleik...@leikhim.com wrote:

 I have just sent off an e-mail to David Howe of NIST Metrology requesting
clarification about this assertion that KTB is revised -3dB.
 
 --
 Joe Leikhim
 
 
 Leikhim and Associates
 
 Communications Consultants
 
 Oviedo, Florida
 
 jleik...@leikhim.com
 
 407-982-0446
 
 WWW.LEIKHIM.COM
 
 
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Re: [time-nuts] Trimble T Lassen 2 - suitableantenna....advice.....questions

[Mike Feher]

Wow, that is indeed narrow. Only 1us out of a 1 second rep rate. That is one
millionth of the rep rate. No wonder analog scopes will not catch it. I'll
have to try it some time. Regards - Mike  

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bob Bownes
Sent: Monday, July 23, 2012 1:06 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Trimble T Lassen 2 -
suitableantennaadvice.questions

The pulse from my T-Bolt is on the order of 1uS wide. I captured it on the
digital scope for posterity and future reference.

http://www.fastbobs.com/pictures/1pps.jpg

Bob




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Re: [time-nuts] DDS in GPSDO design?

[Mike Feher]

With a finite number of bits for phase and amplitude, regardless of total
number of bits. How do you eliminate spurs by design? Thanks - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bruce Griffiths
Sent: Monday, May 28, 2012 12:10 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] DDS in GPSDO design?

Michael Tharp wrote:
 On 05/27/2012 06:23 PM, Bruce Griffiths wrote:
 The principal problem with conventional DDS implementations is phase 
 truncation spurs which can occur close to the desired carrier.
 Virtually all commercial DDS chips produce such phase truncation spurs.

 It is possible to eliminate such spurs if one implements a custom DDS 
 using an FPGA and an external DAC.
 In this case the performance is limited by the DAC.

 How specifically does the FPGA resolve the problem? I have a FPGA 
 already for the phase comparator, it's just a simple matter of 
 figuring out how big of a DAC to get and what data to feed it...

By implementing a design thats phase truncation spur free like:

/Ultra low Phase noise DDS/ , Fred Harris, Chris Dick, Richard Jekel in
Proceedings of SDR06 Technical conference and Product exposition.
Both amplitude and phase errors arise due to phase truncation and its
essential to correct both.

rather than the simplistic technique used in AD (and other) DDS chips where
the phase and amplitude errors due to truncation remain uncorrected.
 Another approach is to use a cascaded mix and divide technique 
 http://www.karlquist.com/FCS95.pdf to restrict the effective tuning 
 range of the DDS.
 The amplitude of DDS generated spurs is thereby significantly reduced.

 Great paper, this looks like it could be interesting as a standalone 
 filter. It's just a little over my head (self-taught digital guy) but 
 since I don't need to hit a home run on the first try, I'll keep it in 
 mind.

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Re: [time-nuts] DDS in GPSDO design?

[Mike Feher]

Thanks - I'll look those over. Just seems the initial accumulator setting
always needs to be known, or preset to a pre-defined number for anything to
help. On top of that to apply a series, even with a limited length, just
would add to settling time or introduce other issues. Regards - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bruce Griffiths
Sent: Monday, May 28, 2012 12:36 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] DDS in GPSDO design?

These Xilinx datasheets indicate the performance of some techniques:

http://www.xilinx.com/support/documentation/ip_documentation/ds794_dds_compi
ler.pdf

http://www.xilinx.com/support/documentation/ip_documentation/dds.pdf

The Taylor series (amplitude and phase) correction technique is the most
effective.

Bruce

Mike Feher wrote:
 With a finite number of bits for phase and amplitude, regardless of 
 total number of bits. How do you eliminate spurs by design? Thanks - 
 Mike

 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell

 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] 
 On Behalf Of Bruce Griffiths
 Sent: Monday, May 28, 2012 12:10 AM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] DDS in GPSDO design?

 Michael Tharp wrote:

 On 05/27/2012 06:23 PM, Bruce Griffiths wrote:
  
 The principal problem with conventional DDS implementations is phase 
 truncation spurs which can occur close to the desired carrier.
 Virtually all commercial DDS chips produce such phase truncation spurs.

 It is possible to eliminate such spurs if one implements a custom 
 DDS using an FPGA and an external DAC.
 In this case the performance is limited by the DAC.

 How specifically does the FPGA resolve the problem? I have a FPGA 
 already for the phase comparator, it's just a simple matter of 
 figuring out how big of a DAC to get and what data to feed it...

  
 By implementing a design thats phase truncation spur free like:

 /Ultra low Phase noise DDS/ , Fred Harris, Chris Dick, Richard Jekel 
 in Proceedings of SDR06 Technical conference and Product exposition.
 Both amplitude and phase errors arise due to phase truncation and its 
 essential to correct both.

 rather than the simplistic technique used in AD (and other) DDS chips 
 where the phase and amplitude errors due to truncation remain uncorrected.

 Another approach is to use a cascaded mix and divide technique 
 http://www.karlquist.com/FCS95.pdf  to restrict the effective 
 tuning range of the DDS.
 The amplitude of DDS generated spurs is thereby significantly reduced.

 Great paper, this looks like it could be interesting as a standalone 
 filter. It's just a little over my head (self-taught digital guy) but 
 since I don't need to hit a home run on the first try, I'll keep it 
 in mind.

 ___
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 https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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Re: [time-nuts] DDS in GPSDO design?

[Mike Feher]

Bruce -

Is the FPGA the same width as the accumulator? Still it seems to me that the
initial conditions of the accumulator at the time of a frequency chance
would matter as well. At least it used to. I agree, in as pipeline
situation, If the FPGA is no more than a look up, there would be no delay.
However, if it actually had to do some number crunching. It would have to be
pretty quick to fit into a pipeline time slot. - Thanks - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bruce Griffiths
Sent: Monday, May 28, 2012 1:44 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] DDS in GPSDO design?

Since the Taylor series correction is done entirely within the FPGA there
should be no settling time issues other than the associated pipeline delay.
It makes use of the untruncated data available (before phase truncation)
within the FPGA.
Of course this doesn't correct for DAC nonlinearity, however this only
contributes harmonics and doesnt generate other spurs.

Bruce


Mike Feher wrote:
 Thanks - I'll look those over. Just seems the initial accumulator 
 setting always needs to be known, or preset to a pre-defined number 
 for anything to help. On top of that to apply a series, even with a 
 limited length, just would add to settling time or introduce other 
 issues. Regards - Mike

 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell


 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] 
 On Behalf Of Bruce Griffiths
 Sent: Monday, May 28, 2012 12:36 AM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] DDS in GPSDO design?

 These Xilinx datasheets indicate the performance of some techniques:

 http://www.xilinx.com/support/documentation/ip_documentation/ds794_dds
 _compi
 ler.pdf

 http://www.xilinx.com/support/documentation/ip_documentation/dds.pdf

 The Taylor series (amplitude and phase) correction technique is the 
 most effective.

 Bruce

 Mike Feher wrote:

 With a finite number of bits for phase and amplitude, regardless of 
 total number of bits. How do you eliminate spurs by design? Thanks - 
 Mike

 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell

 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]
 On Behalf Of Bruce Griffiths
 Sent: Monday, May 28, 2012 12:10 AM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] DDS in GPSDO design?

 Michael Tharp wrote:

  
 On 05/27/2012 06:23 PM, Bruce Griffiths wrote:


 The principal problem with conventional DDS implementations is 
 phase truncation spurs which can occur close to the desired carrier.
 Virtually all commercial DDS chips produce such phase truncation spurs.

 It is possible to eliminate such spurs if one implements a custom 
 DDS using an FPGA and an external DAC.
 In this case the performance is limited by the DAC.

  
 How specifically does the FPGA resolve the problem? I have a FPGA 
 already for the phase comparator, it's just a simple matter of 
 figuring out how big of a DAC to get and what data to feed it...



 By implementing a design thats phase truncation spur free like:

 /Ultra low Phase noise DDS/ , Fred Harris, Chris Dick, Richard Jekel 
 in Proceedings of SDR06 Technical conference and Product exposition.
 Both amplitude and phase errors arise due to phase truncation and its 
 essential to correct both.

 rather than the simplistic technique used in AD (and other) DDS chips 
 where the phase and amplitude errors due to truncation remain
uncorrected.

  
 Another approach is to use a cascaded mix and divide technique
 http://www.karlquist.com/FCS95.pdf   to restrict the effective
 tuning range of the DDS.
 The amplitude of DDS generated spurs is thereby significantly reduced.

  
 Great paper, this looks like it could be interesting as a standalone 
 filter. It's just a little over my head (self-taught digital guy) 
 but since I don't need to hit a home run on the first try, I'll keep 
 it in mind.

 ___
 time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to 
 https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
 and follow the instructions there.



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Re: [time-nuts] Noise source measurement

[Mike Feher]

Javier -

I believe you are indeed close. With the IF BW at 1 MHz the correction is
indeed 60 dB. The post detection filtering by the video filter only makes it
look nicer but does not come into play. I believe there are two correction
factors that you need to take into consideration, that, as I recall, comes
close to about 2.5 dB total. I may be off on that number, but, it is close
to that (I am sure you can Google it). You will read more because the filter
BW is off course not perfect, and the equivalent noise BW is greater than 1
MHz. I believe there is a correction for that. The other, is how the
detector inside the analyzer treats noise instead of a pure sine wave. Those
corrections will get you closer to your expected value, and, maybe the
others are due to your losses. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 (B)
908-902-3831 (C)

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Javier Herrero
Sent: Saturday, October 22, 2011 8:51 AM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] Noise source measurement

Hello all,

Perhaps a bit OT, but I'm measuring the output noise density of a noise 
source at a puntual frequency. I've fed the noise output to a 8566B 
spectrum analyzer, BW set to 1MHz and video BW set to 1kHz so the 
displayed trace is flat. I obtain a measurement of -45dBm, and I 
understand that the noise density then is -105dBm/Hz.

 From design variables, I was expecting a somewhat lower value, around 
-110dBm/Hz, but between the NoiseCom noise source and the output there 
are several things (attenuator, filter, amplifier, directional coupler, 
variable attenuator, ...), so perhaps there are slight differences 
between estimated insertion gains and losses accumulate up to 5dB. 
Before dismount the system and look directly at the noise source output 
and measure the losses/gains of each element, I would like to know if I 
am doing this mesasurement right or am I commiting some mistake?

Thanks! Best regards,

Javier, EA1CRB


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[time-nuts] MIT RADIATION LABORATORY SERIES 1940-1945 (28 VOLS) on eBay

[Mike Feher]

A guy is offering a complete set item # 320727122967 on eBay. I already have
one complete set and lots of duplicates, otherwise I would jump at it. I
like the hard copy a lot better than trying to read them on-line. Regards -
Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


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Re: [time-nuts] DDS'ery

[Mike Feher]

In the old days, HI, we used to use 6 dB/bit for SFDR for the DAC as a rule
of thumb. In practice, it needed to be somewhat better. So, even with 6
dB/bit it would require a minimum of 25 bits. Good thing back then, in the
early 70's I was working on ASW stuff at acoustic frequencies and some of
this was doable. However, we did not require a great SFDR. More recently in
the late 80's and 90's, I was concerned in getting DDSs in the 500 to 1 GHz
range. Lots of RD money and lots of promises, but, no cigar for a real
usable product. 73 - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Ulrich Bangert
Sent: Tuesday, June 21, 2011 5:03 AM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] DDS'ery

John,

as usual I second your opinion and I did have already on my mind to suggest
XILINX's DDS compiler to the group too.

However your statement 

 to provide SFDR up to 150 dB (and I'd notice it if I were 
 getting much less than that in practice.)

has pushed me up! When I tell the compiler to generate me a 150 dB SFDR DDS
then it produces an block with 28 (!) bits output witdh for the DAC. So, I
am asking myself what wonder-chips you may be using as DAC for your DDS that
features a dynamic range high enough to really measure a 150 dB SFDR?

Best regards
Ulrich Bangert, DF6JB

 -Ursprüngliche Nachricht-
 Von: time-nuts-boun...@febo.com 
 [mailto:time-nuts-boun...@febo.com] Im Auftrag von John Miles
 Gesendet: Dienstag, 21. Juni 2011 00:52
 An: 'Discussion of precise time and frequency measurement'
 Betreff: Re: [time-nuts] DDS'ery
 
 
 I'm not familiar with Altera's DDS options, but I will say 
 that Xilinx's DDS compiler is superb.  It can be configured 
 to provide SFDR up to 150 dB (and I'd notice it if I were 
 getting much less than that in practice.)
 
 As Javier hinted, the reason you can't use the MSB directly 
 is that its transition point is not necessarily stationary 
 between cycles of the frequency you're trying to synthesize.  
 It will flop around all over the place.  You need at least a 
 few more bits in most applications -- remember that in an 
 n-bit word, the magnitude represented by the n-1 LSBs is 
 almost as much as the bit-n MSB. 
 
 When DDS technology was first becoming popular in the 1980s, 
 Qualcomm was one of the main vendors, and they required 
 external DACs.  High-speed DACs were pricy and used a lot of 
 power, so I imagine that a great many people tried feeding 
 the MSB directly to the filter, as I did.  It could be 
 feasible at some selected frequencies or at very high 
 clock/output ratios, but in the general case the output 
 signal is just comically awful.  
 
 You would need a truly massive filter to provide the needed 
 flywheel effect to make up for those missing bits.  And it 
 would need to be a BPF, not just an LPF, because not all of 
 the artifacts associated with output quantization are above 
 the desired carrier frequency.  Sometimes the MSB's toggle 
 period is going to be shorter than it should be, and 
 sometimes it's going to be longer.
 
 -- john, KE5FX
 
 
  -Original Message-
  From: time-nuts-boun...@febo.com [mailto:time-nuts- 
 boun...@febo.com] 
  On Behalf Of Luis Cupido
  Sent: Monday, June 20, 2011 9:46 AM
  To: Discussion of precise time and frequency measurement
  Subject: Re: [time-nuts] DDS'ery
  
  Gracias, Javier.
  
  As you read in my previous email I'm basically
  worried about close-in spurs (those that
  will pass through the PLL loop filter).
  
  will digest that 4th section... tks.
  
  
  
  Since I'm inside an FPGA... I'm eager to get
  spurs down without leaving the digital world...
  Anyone knows any literature covering that ?
  
  Thanks.
  
  Luis cupido.
  ct1dmk.
  
  
  
  
  
  On 6/20/2011 4:52 PM, Javier Herrero wrote:
   To reduce the spurii due to quantization distortion. Here is an 
   explanation, in Section 4
  
   http://www.analog.com/static/imported-
  files/tutorials/450968421DDS_Tutorial_rev12-2-99.pdf
  
  
   Regards,
  
   Javier
  
   El 20/06/2011 17:39, Luis Cupido escribió:
   Well, if we really need to filter it out
   we better filter the MSB and square it
   again...
  
   Why having a DAC for ???
  
   Right ?
  
   Luis Cupido.
   ct1dmk.
  
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Re: [time-nuts] DDS'ery

[Mike Feher]

Actually it is (n*Fs +/-Fo), however, they do go down in amplitude as a
SinX/X. Theoretically, they would also be there after the Sin ROM, and the
only one really of concern in the real world is the Fs - Fo, hence the LPF.
When I used to design DDSs in the early 70's, we typically tried to use an
Fs that was about 2.5 times the max desired Fo, to make filtering easier. We
also used discrete parts then :). Now, with the higher speed devices
available a real high Fs can be selected to meet a desired Fmax. Of course
the limit is always being pushed, and, the devices are never fast enough.
Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Graham / KE9H
Sent: Monday, June 20, 2011 11:12 AM
To: time-nuts@febo.com
Subject: Re: [time-nuts] DDS'ery

Luis:

No, not the same.

The most significant bit out of the accumulator has the alias information
on it (Fs +/- Fo), so it still needs to be run through the low pass filter
to clean off the alias signals.  The alias signals manifest themselves 
as jitter,
so no amount of just clipping will remove them.

If your application is not sensitive to the alias frequencies, then OK to
drive out of the DDS directly.

If you are driving something like a mixer in a wide band radio, then you
still need to use the low pass filters.  They don't call them anti-alias 
filters
for no reason.

--- Graham / KE9H

==

On 6/20/2011 9:46 AM, Luis Cupido wrote:
 Folks, a quick one...

 A DDS, that is an accumulator with a DAC followed by a low pass filter 
 and comparator (zero crossing) to produce a square wave to drive a PLL 
 or a MIXER or else (at logic levels).

 Isn't it the very same thing as just using the most significant bit of 
 the accumulator.

 Or am I missing something here ?

 Comments appreciated.
 thanks.

 Luis Cupido.
 ct1dmk.

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Re: [time-nuts] smallest rubidium

[Mike Feher]

For what it is worth, I agree 100%. I have also been top posting for over 30
years.

A lot of times when I open a thread, and, do not see anything but previous
posts, I delete the whole thing. Why should I go all the way to the bottom
to see what someone may have said, or, to even see if there is something
there. Unfortunately, I probably miss out on some good info this way, but, I
do not have the patience to sort through it all. If I have been following
the threads then I know what has been said anyway. If I have not, the latest
top reply might peak my interest. 

Another thing that really annoys me is when people comment inside of a
previous post, about every paragraph/sentence or so. Most of the time it is
difficult to tell what was the previous post and when the new response
begins. 

Just put it all on top. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Rob Kimberley
Sent: Monday, May 23, 2011 9:30 AM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] smallest rubidium

I couldn't resist commenting about how top posting annoys you.
Interestingly, I have always top posted ever since my first email way, way
back. Everyone else I dealt with in business did it that way. It wasn't
until I got involved with groups like this, that it apparently became a
problem. 

It always seemed logical to me to have the answers to a question at the top
i.e. the most recent comment in the chain.

No doubt I'll get a lot of replies both top and bottom about this...
:-)
RK



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Re: [time-nuts] basic question on GPS satellites

[Mike Feher]

Gene -

My main GPS antenna is mounted in the middle of the peak of my Colonial
style house. I do not know if you noticed it when you were here. It has been
up there about 9 years with no problems. 73 - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of W2HX
Sent: Sunday, May 15, 2011 10:19 PM
To: time-nuts@febo.com
Subject: Re: [time-nuts] basic question on GPS satellites

Length is about 12', type is RG-58, antenna is at my window pointing to a
some blue sky (no splitter). I think from the emails from the folks on the
list, before anything, I need to find a better location for the antenna.
Thanks for the reply

73 Eugene W2HX




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Re: [time-nuts] Selecting a used HP sweep/frequency generator

[Mike Feher]

This is amazing - now I have to get one. 73 - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Pete Lancashire
Sent: Thursday, April 14, 2011 3:17 PM
To: Discussion of precise time and frequency measurement
Cc: k6...@comcast.net
Subject: Re: [time-nuts] Selecting a used HP sweep/frequency generator

And if you get a 3314A is can do something non of the others can do

http://www.slack.com/hp3314a.html

-pete

On Thu, Apr 14, 2011 at 11:47 AM,  k6...@comcast.net wrote:
 Bob--

 For that frequency range, I like the 3314A - 1 to 20 MHz with sweep,
bursts, gate, arb, and an easter egg. Lots of modulation capabilities.

 No easy way to synch it to 10MHz, as it runs off an internal crystal clock
(2 MHz?). I've thought about bootlegging it to my house (tbolt) standard,
but haven't done that yet.

 My real RF sweeper is a boat anchor, an old 8660C, which was incredibly
cheap by the pound when I got it...

 I paid around $200 for the 3314A on the usual auction site two or three
years ago; the current batch listed seem high.

 bob k6rtm
 --

 Message: 2
 Date: Thu, 14 Apr 2011 11:38:58 -0400
 From: Bob Bownes bow...@gmail.com
 To: Bob Bownes bow...@gmail.com
 Subject: [time-nuts] Selecting a used HP sweep/frequency generator
 Message-ID: BANLkTi=upy4x2wumn9rpaw-vreu4yw3...@mail.gmail.com
 Content-Type: text/plain; charset=ISO-8859-1

 Thought I would consult the assembled wisdom here.

 I'm looking for an HP frequency generator with sweep capability in the
 1-20Mhz range. I can live with 1-11, and would really love 1-55, but
 1-20 seems to be the most common. Other instruments I already own
 cover 10 and up. The goal here is to have something complementary to
 the 8640B, the 8620, and the 10m-20G sweeper.

 The candidates at present are the 3324 and 3325.

 The questions are:

 1) Of the 3324 and 3325, are there any of the A/B/C/etc variants to
 favour or avoid?

 2) Are there any other candidates to consider?

 This is for home, not work. Cost is, of course, a consideration. I
 already have 10mhz standard, so being able to lock to that is a plus.

 Thanks,
 Bob



 --

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Re: [time-nuts] latest on the lightsquared 'saga'

[Mike Feher]

That sounds neat. My recollection of SAW filters from many moons ago is that
they have a fair amount of insertion loss. One always has to consider
trade-offs. Do you know if it is placed after the antenna and before the
LNA, or, is it after the LNA? Also, you probably meant -159 dBm of
sensitivity, and, I expect that is on a one Hz basis. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Matt Osborn
Sent: Monday, March 07, 2011 2:59 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] latest on the lightsquared 'saga'

iLotus has the new TX Oncore timing receiver with a built in saw
filter and -159db sensitivity.  Has anyone had a chance to put it
through its paces?

-- kc0ukk at msosborn dot com

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Re: [time-nuts] GPS Filter

[Mike Feher]

I used to make some interdigital filters and amplifiers in the early 80's
for MDS TV reception in the 2.3 GHz range. One can easily fabricate a low
loss narrow band filter at 1.5 GHz if need be, and as mentioned before,
antennas should be easy as well. If this really becomes an issue, I am sure
there will be a lot of solutions offered and anyone with some RF experience
will also be able to handle it themselves. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Ziggy
Sent: Friday, March 04, 2011 7:47 PM
To: time-nuts@febo.com
Subject: Re: [time-nuts] GPS Filter

The discussion got me to thinking about how we used to filter out nearby 
interference on amateur TV - namely by using interdigital filters. This 
led to a search for GPS interdigital filters which i did indeed find. 
See Alison Microwave website at 
http://www.amlant.co.uk/DetailsAD430.htm for one example of an 
integrated antenna/filter/preamp. (I'm sure these aren't cheap, but I 
haven't asked.) As for retrofitting, you could add a filter after the 
antenna/amplifier assembly but I might be concerned that the amplified 
GPS antenna is pretty wide and may have trouble with a Lightsquared 
transmitter nearby. There are passive antennas though, and there are 
in-line amps - you'd need to add the filter in between. We made these 
ourselves for 439 and 1296 MHz - GPS L1 isn't much above that so with 
some care it should be doable. The tuning can be finicky though :\

Ziggy

On 03/04/2011 03:31 PM, John Ackermann N8UR wrote:
 Here's a measurement we did a few years ago on the HP 58535A:

http://www.febo.com/pages/hp_gps_splitter/port_1_hp_58535a_two_port_amp.png 


 John
 
 On 3/4/2011 1:31 PM, Bob Camp wrote:
 Hi

 Ok, now it's pretty obvious the RF world near your GPS will be 
 changing a *lot* in the near future. Lightsquared and a bunch of 
 similar outfits will be camping out right next door with very high 
 power gear. They will be running 1.5KW from somewhere in town. GPS is 
 running 30 watts from off planet.

 Has anybody tossed the various HP / Symmetricom GPS splitters on a 
 network analyzer? If so, what do the filters in them look like?

 I probably should corner the market on these things before asking a 
 question like that.

 The new neighbors will be at 1525 to 1559 MHz.  GPS L1 is at 1575.42 
 MHz.  That's what we are using for timing. L2 is down at 1227.5, 
 right now it's mainly military use. Obviously these guys are a bigger 
 deal for civilians than the military.

 So the question is - do the built in splitter filters have any real 
 rejection 15 to 50 MHz off of center?

 Probably worth checking. It would be a pleasant surprise if they 
 turned out to be useful.

 Bob



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Re: [time-nuts] GPS Filter

[Mike Feher]

Well, as you said John, for FWIW. In this case not much. As said low loss,
so increase in noise temp would be minimal, and, if it makes a difference
between an overloaded front end or a 0.5 dB loss in NF, it will be welcome.
Heck, we use filters in front of most of our Satcom LNBs at 21 GHz with
minimal effect. Been there and done that, as the saying goes. If necessary
the small increase in noise temp can easily be overcome by a slightly larger
aperture, especially since a view of the full sky is not really necessary
and birds below certain elevation angles are typically ignored by software
settings of one's own choosing. And again, I was talking about people who
have done this and can do it again. It would not be an issue for me. Regards
- Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of J. Forster
Sent: Friday, March 04, 2011 8:47 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] GPS Filter

I'm not so sure.

A filter ahead of a preamp significantly increases the system Noise
Temperature.

GPS signals are weak and link margins are small. The receiver preamps are
already very low noise.

I'd think that a narrow filter might well drive up the systen NF to the
point it'd be useless.

FWIW,

-John

=


 I used to make some interdigital filters and amplifiers in the early 80's
 for MDS TV reception in the 2.3 GHz range. One can easily fabricate a low
 loss narrow band filter at 1.5 GHz if need be, and as mentioned before,
 antennas should be easy as well. If this really becomes an issue, I am
 sure
 there will be a lot of solutions offered and anyone with some RF
 experience
 will also be able to handle it themselves. Regards - Mike

 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell


 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
 Behalf Of Ziggy
 Sent: Friday, March 04, 2011 7:47 PM
 To: time-nuts@febo.com
 Subject: Re: [time-nuts] GPS Filter

 The discussion got me to thinking about how we used to filter out nearby
 interference on amateur TV - namely by using interdigital filters. This
 led to a search for GPS interdigital filters which i did indeed find.
 See Alison Microwave website at
 http://www.amlant.co.uk/DetailsAD430.htm for one example of an
 integrated antenna/filter/preamp. (I'm sure these aren't cheap, but I
 haven't asked.) As for retrofitting, you could add a filter after the
 antenna/amplifier assembly but I might be concerned that the amplified
 GPS antenna is pretty wide and may have trouble with a Lightsquared
 transmitter nearby. There are passive antennas though, and there are
 in-line amps - you'd need to add the filter in between. We made these
 ourselves for 439 and 1296 MHz - GPS L1 isn't much above that so with
 some care it should be doable. The tuning can be finicky though :\

 Ziggy

 On 03/04/2011 03:31 PM, John Ackermann N8UR wrote:
 Here's a measurement we did a few years ago on the HP 58535A:


http://www.febo.com/pages/hp_gps_splitter/port_1_hp_58535a_two_port_amp.png


 John
 
 On 3/4/2011 1:31 PM, Bob Camp wrote:
 Hi

 Ok, now it's pretty obvious the RF world near your GPS will be
 changing a *lot* in the near future. Lightsquared and a bunch of
 similar outfits will be camping out right next door with very high
 power gear. They will be running 1.5KW from somewhere in town. GPS is
 running 30 watts from off planet.

 Has anybody tossed the various HP / Symmetricom GPS splitters on a
 network analyzer? If so, what do the filters in them look like?

 I probably should corner the market on these things before asking a
 question like that.

 The new neighbors will be at 1525 to 1559 MHz.  GPS L1 is at 1575.42
 MHz.  That's what we are using for timing. L2 is down at 1227.5,
 right now it's mainly military use. Obviously these guys are a bigger
 deal for civilians than the military.

 So the question is - do the built in splitter filters have any real
 rejection 15 to 50 MHz off of center?

 Probably worth checking. It would be a pleasant surprise if they
 turned out to be useful.

 Bob



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Re: [time-nuts] GPS Filter

[Mike Feher]

I used the 0.5 dB number for loss as a worst case. Of course they are
available. They are available even lower, and even at higher frequencies.
Whether or not is trivial is not relevant. What is required is relevant.
This would of course be relevant in small handheld disadvantaged GPS
receivers, but, for roof mounted time-nuts use it should not be a problem.
Even some indoor use it would be fine. If you really feel that you need less
than 0.5 dB of NF, get the numbers. What is the typical RIP from the various
birds at various locations? Then knowing Ga and NF you can calculate C/N and
Eb/No required for the processors to work with acceptable error. Anyway,
enough on this. This is something I can personally handle and am not
worried. Besides, imagine if all of the sudden millions of Cell phones
became useless. Just not going to happen. - Mike   

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: J. Forster [mailto:j...@quik.com] 
Sent: Friday, March 04, 2011 9:09 PM
To: Mike Feher
Cc: 'Discussion of precise time and frequency measurement'
Subject: RE: [time-nuts] GPS Filter

Preamps with NFs under 0.5 dB are available for the 1.5 GHz region. IMO a
doubling of system noise temperature is non-trivial.

-John

===


 Well, as you said John, for FWIW. In this case not much. As said low loss,
 so increase in noise temp would be minimal, and, if it makes a difference
 between an overloaded front end or a 0.5 dB loss in NF, it will be
 welcome.
 Heck, we use filters in front of most of our Satcom LNBs at 21 GHz with
 minimal effect. Been there and done that, as the saying goes. If necessary
 the small increase in noise temp can easily be overcome by a slightly
 larger
 aperture, especially since a view of the full sky is not really necessary
 and birds below certain elevation angles are typically ignored by software
 settings of one's own choosing. And again, I was talking about people who
 have done this and can do it again. It would not be an issue for me.
 Regards
 - Mike

 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell


 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
 Behalf Of J. Forster
 Sent: Friday, March 04, 2011 8:47 PM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] GPS Filter

 I'm not so sure.

 A filter ahead of a preamp significantly increases the system Noise
 Temperature.

 GPS signals are weak and link margins are small. The receiver preamps are
 already very low noise.

 I'd think that a narrow filter might well drive up the systen NF to the
 point it'd be useless.

 FWIW,

 -John

 =


 I used to make some interdigital filters and amplifiers in the early
 80's
 for MDS TV reception in the 2.3 GHz range. One can easily fabricate a
 low
 loss narrow band filter at 1.5 GHz if need be, and as mentioned before,
 antennas should be easy as well. If this really becomes an issue, I am
 sure
 there will be a lot of solutions offered and anyone with some RF
 experience
 will also be able to handle it themselves. Regards - Mike

 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell



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[time-nuts] Attn: Steve - K8JQ - GPS Antenna splitters

[Mike Feher]

Sorry to the rest of the group for this post. Steve - my emails to you keep
on getting lost it seems. If you provide a phone number I will call you.
Thanks - Mike

To the rest who purchased them - they were all shipped last week. Thanks -
Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: Mike Feher [mailto:mfe...@eozinc.com] 
Sent: Friday, February 04, 2011 9:26 PM
To: 'Discussion of precise time and frequency measurement'
Subject: RE: [time-nuts] GPS Antenna splitters

I still have some Symmetricom 58535A two way splitters available. Specs are
available on the Symmetricom web site. The pricing is as follows:

1 58535A  $35 plus $ 5.20 priority flat rate shipping
2 58535A  $65 plus $ 5.20 priority flat rate shipping
4 58535A $120 plus $10.95 priority flat rate shipping 

Thanks  Regards - Mike

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


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Re: [time-nuts] GPS Antenna splitters

[Mike Feher]

Hi Mark -

I have shipped a lot of these to Canada. The shipping cost is the same for
one or two units, and it is $11.95. If you pay by PayPal please add 4.5% on
to the total for their fees. PayPal to n...@eozinc.com . Thanks  73 - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Mark Spencer
Sent: Monday, February 07, 2011 10:35 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] GPS Antenna splitters

Mike, are able to ship to Canada and do you know roughly what the shipping
would 
be ?

I would be happy to purchase 2 of them so long as the shipping is
reasonable.    
I can pay via paypal or send a bank draft in USD.

Many thanks
Mark Spencer VE7AFZ



- Original Message 
From: Mike Feher mfe...@eozinc.com
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Sent: Fri, February 4, 2011 6:25:31 PM
Subject: Re: [time-nuts] GPS Antenna splitters

I still have some Symmetricom 58535A two way splitters available. Specs are
available on the Symmetricom web site. The pricing is as follows:

1 58535A  $35 plus $ 5.20 priority flat rate shipping
2 58535A  $65 plus $ 5.20 priority flat rate shipping
4 58535A $120 plus $10.95 priority flat rate shipping 

Thanks  Regards - Mike

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Dave M
Sent: Friday, February 04, 2011 8:16 PM
To: TimeNuts
Subject: [time-nuts] GPS Antenna splitters

Has anyone measured the gain (or loss) of the Minicircuits ZAPD-3DB-1575-3 
GPS antenna splitter?  I've seen a number on the auction site, and am 
wondering if they have any gain.  I see the 3DB in the model number, but 
don't know if it's gain or loss.
I have a TBolt and an HP Z3801A.  I can  use the antenna with only one 
receiver at a time, but would like to run them concurrently.    Since I'm 
using a 25db gain bullet antenna, I certainly don't want to lose any signal.

If the ZAPD-3DB-1575-3 splitter doesn't provide any gain internally, which 
model splitter(s) can you recommend?

David
dgminala at mediacombb dot net

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Re: [time-nuts] GPS Antenna splitters

[Mike Feher]

I still have some Symmetricom 58535A two way splitters available. Specs are
available on the Symmetricom web site. The pricing is as follows:

1 58535A  $35 plus $ 5.20 priority flat rate shipping
2 58535A  $65 plus $ 5.20 priority flat rate shipping
4 58535A $120 plus $10.95 priority flat rate shipping 

Thanks  Regards - Mike

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Dave M
Sent: Friday, February 04, 2011 8:16 PM
To: TimeNuts
Subject: [time-nuts] GPS Antenna splitters

Has anyone measured the gain (or loss) of the Minicircuits ZAPD-3DB-1575-3 
GPS antenna splitter?  I've seen a number on the auction site, and am 
wondering if they have any gain.  I see the 3DB in the model number, but 
don't know if it's gain or loss.
I have a TBolt and an HP Z3801A.  I can  use the antenna with only one 
receiver at a time, but would like to run them concurrently.Since I'm 
using a 25db gain bullet antenna, I certainly don't want to lose any signal.

If the ZAPD-3DB-1575-3 splitter doesn't provide any gain internally, which 
model splitter(s) can you recommend?

David
dgminala at mediacombb dot net

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Re: [time-nuts] power spectrum of hard limiter output

[Mike Feher]

Even the original is a good classic on PLLs. I have an original photocopy of
the typed pre-publication volume, as well as the actual book. Regarding hard
limiters, we did a lot of study on their behavior on the resulting power
spectra. We use a one bit quantizer of ASW signals and then displayed the
output power spectra on graph paper, back in the late 60's early 70's. I
have some of the original papers on the effects of hard limiting of signals,
with AWGN, however, they are downstairs in the inner sanctum and to find
them would be a challenge. Maybe if I get ambitious I'll venture downstairs
and see if I can locate the folders. Would be glad to scan them. Regards -
Mike   

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Magnus Danielson
Sent: Wednesday, January 26, 2011 12:34 AM
To: time-nuts@febo.com
Subject: Re: [time-nuts] power spectrum of hard limiter output

On 26/01/11 00:35, ehydra wrote:
 Hi Magnus -

 What book? This one maybe:
 Gardner F M PHASELOCK TECHNIQUES Wiley  Sons 1966

Yes, but there is later revisions of it. A classic on PLLs.

Cheers,
Magnus

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Re: [time-nuts] An (unknown?) nasty feature of the DDS principlefortime nuts applications

[Mike Feher]

Well, do not feel bad. I am now in my 66th year and still learning. BTW, I
built my first DDS back around 1970. Hard to believe. About the same time
that I built my first digital filter. Used all discrete components and back
then we still called them recursive and non-recursive. We never heard the
term DSP till much much later. I remember using the Remez Exchange
Algorithm to go from the S plane to the Z plane. Of course we also used the
common Matched Z and others as well. My senior project in the late 60's
was a switched capacitor filter. Seems like yesterday, and now I am an old
man with 5 grandkids :). Regards - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Ulrich Bangert
Sent: Tuesday, January 25, 2011 2:01 PM
To: Discussion of precise time and frequency measurement
Cc: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] An (unknown?) nasty feature of the DDS
principlefortime nuts applications

Bob,
I don't know the 33250 from my own experience but after all my Stanford
Research DS345 buy on ebay may not have been the best decision in my life.
At best I can say that I learn something new every day despite being at the
childish age of 55!

Ulrich Bangert
Ortholzer Weg 1
D-27243 Gross Ippener
Germany

Am 25.01.2011 um 18:07 schrieb Bob Camp li...@rtty.us:

 Hi
 
 Jitter from the sawtooth phase modulation on a DDS output is indeed a very
 real thing. I have an Agilent 33250A generator sitting here on the bench
 that makes a very nice variable jitter signal source.
 
 Bob 
 
 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
 Behalf Of Ulrich Bangert
 Sent: Tuesday, January 25, 2011 9:59 AM
 To: 'Discussion of precise time and frequency measurement'
 Subject: Re: [time-nuts] An (unknown?) nasty feature of the DDS
 principlefortime nuts applications
 
 Ahhh,
 
 I see what you mean because a few pages later there is word of a phase
 accumulator. But this phase accumulator is a part of the electronics that
 is responsible for generating the control voltage of a VCO that enables
the
 device to produce odd frequencies despite the integer dividers in the main
 loop. That IS different from what a phase accumulator's task is in a DDS.
 
 73s de Ulrich, DF6JB 
 
 -Ursprungliche Nachricht-
 Von: time-nuts-boun...@febo.com 
 [mailto:time-nuts-boun...@febo.com] Im Auftrag von Ulrich Bangert
 Gesendet: Dienstag, 25. Januar 2011 15:35
 An: 'Discussion of precise time and frequency measurement'
 Betreff: Re: [time-nuts] An (unknown?) nasty feature of the 
 DDS principlefor time nuts applications
 
 
 Gerhard,
 
 see page 8.6ff of the service manual to see that the HP3325 
 is not DDS based but uses a Fractional N Synthesizer scheme 
 which is something completely different and is not prone to 
 the described effects. Nevertheless it is true that the 
 HP3325 contibutes phase noise to the measurement but I had 
 anticipated that this was clear to everybode in the auditorium.
 
 73s de Ulrich, DFJB
 
 -Ursprungliche Nachricht-
 Von: time-nuts-boun...@febo.com
 [mailto:time-nuts-boun...@febo.com] Im Auftrag von dk...@arcor.de
 Gesendet: Dienstag, 25. Januar 2011 15:14
 An: time-nuts@febo.com
 Betreff: Re: [time-nuts] An (unknown?) nasty feature of the 
 DDS principle for time nuts applications
 
 
 
 Don't forget that your HP3325 is DDS-based, too, so it adds
 its own phase error sawtooth.
 
 73, Gerhard dk4xp
 
 
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Re: [time-nuts] Symmetricom Launches CSAC Product for Precise Timing and Sync...

[Mike Feher]

Looks familiar Said. Regards - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf 
Of saidj...@aol.com
Sent: Tuesday, January 18, 2011 2:37 PM
To: time-nuts@febo.com
Subject: Re: [time-nuts] Symmetricom Launches CSAC Product for Precise Timing 
and Sync...

Here is a link to the press release with more technical details and  
pictures:
 
_http://www.eetimes.com/electronics-news/4212176/Chip-scale-atomic-clock-app
roaches-performance-of-modules-2_ 
(http://www.eetimes.com/electronics-news/4212176/Chip-scale-atomic-clock-approaches-performance-of-modules-2)
 
 


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Re: [time-nuts] Hammond Boxes Available -

[Mike Feher]

Eric -

Not at all. I can use the room for all the other junk I buy. I appreciate
it. Thanks - Mike

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Eric Garner
Sent: Saturday, January 01, 2011 1:05 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Hammond Boxes Available -

Mike,

Do you mind if I forward your email to my local dorkbot group to see if
anyone is interested in your Hammond boxes?

Sent from my Banana jr (tm) Mobile Device

On Dec 31, 2010, at 7:49 PM, Mike Feher mfe...@eozinc.com wrote:

 Sorry for the on-line post. I thought it was sent to me direct. Best of
 time-nut happiness in 2011 - Mike
 
 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell
 
 
 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
 Behalf Of Mike Feher
 Sent: Friday, December 31, 2010 10:39 PM
 To: 'Discussion of precise time and frequency measurement'
 Subject: Re: [time-nuts] Hammond Boxes Available -
 
 Stan -
 
 Too many, HI. You would do better getting 3 as the shipping would be the
 same. I can let you have 3 for $22 plus the $10.70 shipping. You decide.
73
 - Mike
 
 Mike B. Feher, N4FS
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell
 
 
 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
 Behalf Of Stan, W1LE
 Sent: Friday, December 31, 2010 10:32 PM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] Hammond Boxes Available -
 
 Hello Mike,
 
 Any boxes left ?
 
 I am looking for 2 each sent by mail to zip 02644.
 
 Thanks   Stan, W1LE
 
 
 On 12/21/2010 1:51 PM, Mike Feher wrote:
 I have a quantity of NOS Hammond boxes available. These are model number
 1598HBK. Mouser is the cheapest source for these that I found on a quick
 search. These are considerably larger than the hard drive enclosures
 previously discussed, and, these are also plastic with aluminum front and
 back plates. They still make excellent small project boxes. Here is the
 Mouser link, you can find others with better photos:
 
 

http://www.mouser.com/ProductDetail/Hammond/1598HBK/?qs=3vio67wFuYpsW%252byy
 vIs3Bw%3D%3D
 
 My pricing is:
 
 1 unit   - $8.00
 2 units  - $15.00
 4 units  - $27.00
 10 units - $60.00
 
 Shipping will be extra, but only actual shipping cost, by your preferred
 method. Each box weighs 1 lb and 6 oz. Thanks  Merry Christmas to all -
 Mike
 
 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell
 
 
 
 
 ___
 time-nuts mailing list -- time-nuts@febo.com
 To unsubscribe, go to
 https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
 and follow the instructions there.
 
 
 
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 To unsubscribe, go to
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 and follow the instructions there.
 
 
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 To unsubscribe, go to
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Re: [time-nuts] Hammond Boxes Available -

[Mike Feher]

Stan -

Too many, HI. You would do better getting 3 as the shipping would be the
same. I can let you have 3 for $22 plus the $10.70 shipping. You decide. 73
- Mike

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Stan, W1LE
Sent: Friday, December 31, 2010 10:32 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Hammond Boxes Available -

Hello Mike,

Any boxes left ?

I am looking for 2 each sent by mail to zip 02644.

Thanks   Stan, W1LE


On 12/21/2010 1:51 PM, Mike Feher wrote:
 I have a quantity of NOS Hammond boxes available. These are model number
 1598HBK. Mouser is the cheapest source for these that I found on a quick
 search. These are considerably larger than the hard drive enclosures
 previously discussed, and, these are also plastic with aluminum front and
 back plates. They still make excellent small project boxes. Here is the
 Mouser link, you can find others with better photos:


http://www.mouser.com/ProductDetail/Hammond/1598HBK/?qs=3vio67wFuYpsW%252byy
 vIs3Bw%3D%3D

 My pricing is:

 1 unit   - $8.00
 2 units  - $15.00
 4 units  - $27.00
 10 units - $60.00

 Shipping will be extra, but only actual shipping cost, by your preferred
 method. Each box weighs 1 lb and 6 oz. Thanks  Merry Christmas to all -
 Mike

 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell




 ___
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Re: [time-nuts] Hammond Boxes Available -

[Mike Feher]

Sorry for the on-line post. I thought it was sent to me direct. Best of
time-nut happiness in 2011 - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Mike Feher
Sent: Friday, December 31, 2010 10:39 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] Hammond Boxes Available -

Stan -

Too many, HI. You would do better getting 3 as the shipping would be the
same. I can let you have 3 for $22 plus the $10.70 shipping. You decide. 73
- Mike

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Stan, W1LE
Sent: Friday, December 31, 2010 10:32 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Hammond Boxes Available -

Hello Mike,

Any boxes left ?

I am looking for 2 each sent by mail to zip 02644.

Thanks   Stan, W1LE


On 12/21/2010 1:51 PM, Mike Feher wrote:
 I have a quantity of NOS Hammond boxes available. These are model number
 1598HBK. Mouser is the cheapest source for these that I found on a quick
 search. These are considerably larger than the hard drive enclosures
 previously discussed, and, these are also plastic with aluminum front and
 back plates. They still make excellent small project boxes. Here is the
 Mouser link, you can find others with better photos:


http://www.mouser.com/ProductDetail/Hammond/1598HBK/?qs=3vio67wFuYpsW%252byy
 vIs3Bw%3D%3D

 My pricing is:

 1 unit   - $8.00
 2 units  - $15.00
 4 units  - $27.00
 10 units - $60.00

 Shipping will be extra, but only actual shipping cost, by your preferred
 method. Each box weighs 1 lb and 6 oz. Thanks  Merry Christmas to all -
 Mike

 Mike B. Feher, EOZ Inc.
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960 office
 908-902-3831 cell




 ___
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 To unsubscribe, go to
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[time-nuts] GPS Antenna Splitters Symmetricom 58535A Available

[Mike Feher]

This discussion prompted me to remind list members that I still have some of
the subject smart GPS splitters available. These are brand new in original
wrapping. The pricing is:

1 58535A  $35 plus $ 4.95 priority flat rate shipping
2 58535A  $65 plus $ 4.95 priority flat rate shipping
4 58535A $120 plus $10.70 priority flat rate shipping

I am not certain, but, it is possible that USPS flat rate priority may go up
in 2011. BTW, flat rate is not that much more to other countries, and, I do
not mind filing out the customs forms.

Best to all in 2011. Regards - Mike


Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Chris Albertson
Sent: Thursday, December 30, 2010 6:26 PM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] GPS Antenna

A few questions about GPS antenna


1) I read the Thunderbolt user manual and did not find any meaningful
spec on the antenna except that it is amplified and uses DC power in
the coax.  What signal level is the Thunderbolt expecting?   oes it
want a 24dB antenna or more or much less?

2) I want to feed two GPS units with one roof mounted antenna.  I
figure that splitters are just a transformers and will not pass DC to
power the antenna.  There must be an easy way around this.

3) Do people really run coax straight from a GPS antenna into their
house with no protection from lightening?  Maybe a GPS antenna is a
small target compared to a 100 foot wire antenna in Florida

-- 
=
Chris Albertson
Redondo Beach, California


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Re: [time-nuts] what is the best way to multiply a 10 Mhz signal?

[Mike Feher]

Interesting. When I used to use and build DDSs back in the early 70's, we
typically used 2.56 times the maximum required frequency for a clock, to get
above Nyquist and allow adequate filtering stop-band rejection. At the time
we could not go much higher due to limitations in device speeds, especially
the D/A. Today you can easily use a much higher clock frequency which would
simplify filtering and reduce gain variations. At 70 MHz clock you are only
at 2.333 Nyquist. Even at 2.56 by the time you get to your desired goal of
30 MHz, you will have what looks just about like a square wave. So,
filtering will be a must, and, after filtering, you will find that your
amplitude output will greatly decrease with frequency. The other question is
phase noise objectives. If that is not a real concern, then as suggested,
maybe a simple locked VCO would be the way to go. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Stephen Farthing
Sent: Tuesday, December 21, 2010 12:57 PM
To: Richard (Rick) Karlquist; time-nuts@febo.com
Subject: Re: [time-nuts] what is the best way to multiply a 10 Mhz signal?

Hi Rich

Thanks for the replyI have an AD9834 DDS chip I want to use for a
Frequency generator with an accuracy of 1 Hz from 0-30 Mhz. . This part can
be clocked at 75 Mhz - but unlike other DDS chips seems to have no internal
clock multipliers. So it seems to me if I can some how generate a 70 Mhz
clock signal from my rubidium standard I can solve the problem.

73s Steve

On 21 December 2010 17:36, Richard (Rick) Karlquist
rich...@karlquist.comwrote:

 I used to be in the synthesizer business (Zeta Labs)
 in a previous life.  I learned to ask the customers:
 what you are trying to accomplish as the end goal,
 before tackling a messy problem like multiplying by
 7.  Maybe you don't need to multiply by 7, but we
 can't tell from your question.

 Rick Karlquist N6RK


 On 12/21/2010 8:35 AM, Stephen Farthing wrote:

 Hi everyone,

 I want to multiply the output from my Efratom 101 (10Mhz) to clock a DDS
 at
 70 Mhz. Has anyone tried this?

 Regards,

 Steve G0XAR




-- 
It is vain to do with more that which can be done with less.
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[time-nuts] Hammond Boxes Available -

[Mike Feher]

I have a quantity of NOS Hammond boxes available. These are model number
1598HBK. Mouser is the cheapest source for these that I found on a quick
search. These are considerably larger than the hard drive enclosures
previously discussed, and, these are also plastic with aluminum front and
back plates. They still make excellent small project boxes. Here is the
Mouser link, you can find others with better photos:

http://www.mouser.com/ProductDetail/Hammond/1598HBK/?qs=3vio67wFuYpsW%252byy
vIs3Bw%3D%3D

My pricing is:

1 unit   - $8.00
2 units  - $15.00
4 units  - $27.00
10 units - $60.00

Shipping will be extra, but only actual shipping cost, by your preferred
method. Each box weighs 1 lb and 6 oz. Thanks  Merry Christmas to all -
Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell




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Re: [time-nuts] What is the best way to multiply a 10 Mhz

[Mike Feher]

The 6 mixer scheme was my first thought for lowest PN. That way you do not
get 20logN, but you just get the RMS sum of the noise power each time. That
would be 3 dB to get to 20 MHz, and, each time the sum becomes less than 3
dB, as the highest frequency dominates. It would only degrade approximately
a total of 10 dB vs. the 17 dB from a regular times 7. Regards - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bill Hawkins
Sent: Tuesday, December 21, 2010 2:55 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] What is the best way to multiply a 10 Mhz

So, two doublers for 40 MHz and a tripler for 30 and then
mix to get 70? What happens to phase noise when you do that?
Is it as bad as a PLL?

Seems like you ought to get adequate harmonic rejection.

What about six mixers to get 20, 30, 40, 50, 60, and 70 MHz?

Chips and tank coils are cheap, no?

Bill Hawkins


-Original Message-
From: Burt I. Weiner
Sent: Tuesday, December 21, 2010 1:39 PM

It would seem the most jitter free way to do it would be to simply 
multiply it up like we used to do.  Some reasonably Hi-Q LC circuits 
could make a nice flywheel and filter out other signals at the same 
time.  Once you have it to the desired signal frequency you could 
condition it to clock your DDS.

Am I missing something here?  Wouldn't be the first time, ya know!

Burt, K6OQK


Subject: Re: [time-nuts] what is the best way to multiply a 10 Mhz
 signal?


On 21/12/10 16:35, Stephen Farthing wrote:
  Hi everyone,
 
  I want to multiply the output from my Efratom 101 (10Mhz) to clock a DDS
at
  70 Mhz. Has anyone tried this?
 
  Regards,
 
  Steve G0XAR



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Re: [time-nuts] ok, newbie questions

[Mike Feher]

Said -

Hope you had a great Thanksgiving. I would think that buffer better be real
good. Otherwise it could impact the loop characteristics, since the OCXO
output is sampled and fed back. Regards - mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-901-9193 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Said Jackson
Sent: Saturday, November 27, 2010 1:22 PM
To: w...@w2hx.com; Discussion of precise time and frequency measurement
Cc: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] ok, newbie questions

I was thinking to tap-off the Ocxo itself with a small buffer and bypass all
of the internal stuff. Will report on that later..

Sent from my iPad



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Re: [time-nuts] First post - please disregard

[Mike Feher]

Go for it Gene - 73 - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-901-9193 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of W2HX
Sent: Thursday, November 25, 2010 11:12 PM
To: time-nuts@febo.com
Subject: [time-nuts] First post - please disregard

Getting ready to make a post and wanted to see if this list supports html or
only plain text and to see how urls are handled. (trying to avoid a mess of
a first post)

 

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemitem=270515147719ssPageName=
STRK:MEWAX:IT item=270515147719ssPageName=STRK:MEWAX:IT

 

 

73 Eugene W2HX

 

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Re: [time-nuts] First post - please disregard yet again

[Mike Feher]

BTW - I have some of those Thunderbolts as well as the T-30B power supplies
if that is what you are looking for - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-901-9193 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of W2HX
Sent: Thursday, November 25, 2010 11:17 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] First post - please disregard yet again

Yikes. That didn't look so good. One last attempt to enclose the url in
chevrons . If that doesn't work, I'll resort to tinyurl.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemitem=270515147719ssPageName=
STRK:MEWAX:IT


73 Eugene W2HX

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of W2HX
Sent: Thursday, November 25, 2010 11:12 PM
To: time-nuts@febo.com
Subject: [time-nuts] First post - please disregard

Getting ready to make a post and wanted to see if this list supports html or
only plain text and to see how urls are handled. (trying to avoid a mess of
a first post)

 

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemitem=270515147719ssPageName=
STRK:MEWAX:IT item=270515147719ssPageName=STRK:MEWAX:IT

 

 

73 Eugene W2HX

 

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Re: [time-nuts] ADEV

[Mike Feher]

10 MHz locked LNBs do not use a separate connector. Everything goes down/up
the single main coax. The typical L-band down-converted frequency and the 10
MHz are easily separated, as is the DC. These are definitely not
inexpensive. Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-901-9193 cell

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of jimlux
Sent: Sunday, November 14, 2010 11:49 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] ADEV

David I. Emery wrote:

   3. External reference LNBs with 10 MHz (pretty universal) going
 up the cable that also carries power and brings the L band signal down.
 I'm not entirely sure how many of these designs simply bandpass filter
 and then limit the 10 MHz and use that directly as a PLL reference and
 how many phase lock a VCXO to the 10 MHz coming in.  Otherwise similar
 (and often  derived from designs for) the internal reference PLL types
 in 2 above.

And, I'll bet those are fairly pricey.. (after all, it needs another 
connector, and that's a price sensitive application..)



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Re: [time-nuts] ext ref LNB Re: ADEV

[Mike Feher]

Well, that I do not know. The majority of Ku  Ka LNBs for home TV use are
using free running DRO's. I have a bunch of them, and never ran across any
locked ones, except for some of the ones used for internet service. My real
experience is what we use in military satcom terminals at Ku and Ka bands,
with apertures from 0.6 to 9.2 meters, and they are all locked to an
external 10 MHz reference. I doubt if you will see any major dumping of
those. Especially now, because of strict ITAR. Even if one can buy it
directly from the manufacturer, once the military has owned it, they will
probably dispose of it in such a way that we will not see them on ebay.
Regards - Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-901-9193 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of jimlux
Sent: Monday, November 15, 2010 9:21 AM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] ext ref LNB Re: ADEV

Mike Feher wrote:
 10 MHz locked LNBs do not use a separate connector. Everything goes
down/up
 the single main coax. The typical L-band down-converted frequency and the
10
 MHz are easily separated, as is the DC. These are definitely not
 inexpensive. Regards - Mike 
 


Ah.. but the question is really not whether the new price is cheap, 
but whether there's some reason why someone would be doing a massive 
refit, and dumping lots of these on the market surplus.

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Re: [time-nuts] ext ref LNB Re: ADEV

[Mike Feher]

The military Ka band is 20.2 to 21.2 on receive and 30 to 31 on transmit.
Norsat of course has been making these for about 15 years, one of the first.
Back when I was working on Milstar 25 years ago, with the same receive
frequency, even the NF was classified. No, it does not make sense, but, that
was the way it was. I just had to deal with some ITAR related issues, where,
COTS equipment is being used, yet, it is now built for, or owned by the
military, and, while the hardware is not classified, it is restricted, even
as to who may work on it. I am just saying, do not hold your breath to see
them coming on the military surplus market. Regards- Mike

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-901-9193 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of jimlux
Sent: Monday, November 15, 2010 10:16 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] ext ref LNB Re: ADEV

Mike Feher wrote:
 Well, that I do not know. The majority of Ku  Ka LNBs for home TV use are
 using free running DRO's. I have a bunch of them, and never ran across any
 locked ones, except for some of the ones used for internet service. My
real
 experience is what we use in military satcom terminals at Ku and Ka bands,
 with apertures from 0.6 to 9.2 meters, and they are all locked to an
 external 10 MHz reference. I doubt if you will see any major dumping of
 those. Especially now, because of strict ITAR. Even if one can buy it
 directly from the manufacturer, once the military has owned it, they will
 probably dispose of it in such a way that we will not see them on ebay.
 Regards - Mike


I doubt the LNB is export controlled.. It's unlikely to have an 
exotically low noise temperature, they're not cryogenic, they don't use 
components with dual-use, it's just part of a receiver.  If you go to 
the NORSAT website, for instance, they don't make much mention of export 
controls  (yeah, I'm sure the invoice/quote would have export 
boilerplate on it the contents of this have not been reviewed... use, 
sale, distribution may require license...)

http://www.norsat.com/lnb/blog

And I note that the datasheet's pretty sketchy on the external reference 
LNBs.. They give phase noise as follows (for Ku band, 10.75 GHz LO):
-75dBc/Hz @ 1kHz
-85 @ 10k
-95 @ 100k

But they don't say whether that's added to the reference noise, or 
that's the outside the loop noise, or what..

What's interesting is that the Ka-band LNB (for 18-19 GHz, which is low 
Ka, to my thinking.. I think 30 when I think Ka).. the noise is actually 
lower
-65 @ 1k
-75 @ 10k
-95 @ 100k
-100 @ 1M

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Re: [time-nuts] 5 and 10 MHz crystal filters

[Mike Feher]

Rick -

Unless I  misunderstood, I do not believe what you said is correct. A
crystal filter  can indeed improve the far out phase noise of a crystal
oscillator. The oscillator's noise is not only a function of the crystal,
but, the combination of the crystal noise and the amplifier noise used for
feedback and the Q of that circuit. All of those additional components
degrade crystal noise. Consequently, a 100 Hz wide filter at 10 MHz can
really do a nice job on just a decent 10 MHz oscillator. Lincoln Labs proved
this in their EDM of a satcom system in the early 80's that then I took over
in industry to replicate and improve in 1986. We did have a 10 MHz crystal
filter in there for cleanup. In our application, the final transmit
frequency was close to 45 GHz, and it needed to be very clean, even after an
optimal architecture used to get us up there. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-901-9193 cell


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Richard (Rick) Karlquist
Sent: Monday, November 15, 2010 4:44 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5 and 10 MHz crystal filters

A friendly warning about crystal filters.  Crystals, whether
used in an oscillator or filter, have intrinsic phase noise.
You cannot improve the phase noise of a crystal oscillator
with a crystal filter unless the filter crystals have lower
phase noise than the oscillator crystals.  In general, post
filtering of an oscillator is rarely done for the reasons
I mentioned.  One place where it made sense was in the HP
8662 with the 640 MHz output option where a 10811 is multiplied to 80
MHz and then filtered to reduce the noise floor.  It is further
multiplied to 640 MHz and filtered again by a SAW filter,
that was made at HP in those days.  As others have mentioned,
filter characteristic impedance is a function of the crystal
physics.  There is a specific impedance that you must use for
a given bandwidth.  Fortunately, it is easy to put transformers
at the ports to convert to 50 ohms.

Rick Karlquist
N6RK

On 11/15/2010 7:44 AM, John Ackermann N8UR wrote:
 I'd like to find a couple of 5.0 and/or 10.0 MHz crystal filters,
 preferably configured for use in-line with 50 ohm coax.

 I've done some googling but don't find anyone selling these as a stock
 item. Do they exist? Any pointers would be appreciated. Used/surplus is
 fine (even preferable).

 Thanks!

 John

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