So, I just recently started trying to resurrect a Spectracom 8160A reference
oscillator. I'm assuming this is proposed WWVB change going to bite me in the
butt on this project as well. Not sure how it differs from units like the HP
117, but my understanding is that most of the old VLF receivers
In message Pine.LNX.4.64.1203170042050.2576@tesla, Marek Peca writes:
My only argument against your versatile and well-performing solution is
that it is a little bit overkill.
As if running a handfull precision oscillators just for fun isn't
overkill also ? :-)
In other words, it would be
Moin!
On Fri, 16 Mar 2012 13:45:04 +
Poul-Henning Kamp p...@phk.freebsd.dk wrote:
Hmm.. i someday have to look for a good introdcution into this stuff
that doesn't rely on a lot of math. All the books i have rely at least
on Laplace.. often on z-transformation as well. And that math isn't
On Fri, 16 Mar 2012 20:02:27 -0700
gary li...@lazygranch.com wrote:
I lost track of who wrote this, but why is it assume a ferrite rod has
non-linear phase. [Group delay error I presume). Now I assume this
presumes the rod is used in a LC circuit, but if the Q is not high, the
phase
Hello all,
a friend purchased from the bay a subj. in the LPRO configuration.
After some problems encountered during the first power ups, he asked for
help - I'm passing the questions further...
After about 9 minutes of warm-up from room temperature (22°C) the lock
signal goes low, but after
In message 20120317104723.8c1832454f14a3f91a4fb...@kinali.ch, Attila Kinali w
rites:
That said, i think this can be ignored for all practical purposes
in an VLF receiver, as the enviromental changes in the atmospheric
signal path are much larger than the small error you get from the
filter. But
On Sat, 17 Mar 2012 10:01:13 +
Poul-Henning Kamp p...@phk.freebsd.dk wrote:
That said, i think this can be ignored for all practical purposes
in an VLF receiver, as the enviromental changes in the atmospheric
signal path are much larger than the small error you get from the
filter. But
In message 2012031719.9536107ebf82050fe14ee...@kinali.ch, Attila Kinali w
rites:
On Sat, 17 Mar 2012 10:01:13 +
Could you explain why? Yes, you need a higher BW for Loran-C,
but the phase(f) function will give you only a distortion of
the signal and a constant time delay in your signal
I've designed filters for datacom chips. I know filtering. My point is the
original author is making some assumptions in the design which are not stated.
What I don't have a lot of hands on experience is with open circuit magnetics.
(I do with closed circuit magnetics.) But I claim if the
On 16 March 2012 16:22, Rix Seacord eseac...@verizon.net wrote:
Luckily, I use PayPal for most of my online purchases.
From the experience of a friend, who bought something eBay that needed
refunding by Paypal, it was a long complex process
1) Buy bandbag from eBay she believed was a fake.
2)
Patent Pending only means that if you copy the design and sell it, some time
in the future (if and when the patent is granted), you may have to stop. You
will not have to buy back your products or pay anything or be required to
license for past use once the patent is granted as long as you stop
On Sat, 17 Mar 2012 10:15:17 +
Poul-Henning Kamp p...@phk.freebsd.dk wrote:
In message 2012031719.9536107ebf82050fe14ee...@kinali.ch, Attila Kinali
w
rites:
On Sat, 17 Mar 2012 10:01:13 +
Could you explain why? Yes, you need a higher BW for Loran-C,
but the phase(f) function
On Sat, 17 Mar 2012 10:27:03 +
li...@lazygranch.com wrote:
What I don't have a lot of hands on experience is with open circuit
magnetics. (I do with closed circuit magnetics.) But I claim if the
ferrite rod antenna is not capacitively loaded to resonate at the
comm frequency, then there
On Sat, 17 Mar 2012 10:15:17 +
Poul-Henning Kamp p...@phk.freebsd.dk wrote:
Either you need to characterize the exact behaviour of your filter
and build the necessary compensation for its phase/frequency behaviour
into your receiver, or you need a very flat filter (both freq+phase)
in
Rich,
I would love to have a set of the pictures.
Joe
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Rich
Sent: Friday, March 16, 2012 3:05 PM
To: time-nuts@febo.com
Subject: Re: [time-nuts] FE5680A
This is my first post here.
Any filter's group delay can be equalized by all pass filters.
Delay builds up at the filter corner. Since everything in the real world
is causal, you add delay outside that corner frequency but in the
passband to equalize it. This is to say, you can't remove delay, but
just add it to flatten
Hello, gary,
I lost track of who wrote this, but why is it assume a ferrite rod has
non-linear phase. [Group delay error I presume). Now I assume this presumes
the rod is used in a LC circuit, but if the Q is not high, the phase
linearity won't necessarily be bad.
Basically I'd like to hear
On Fri, Mar 16, 2012 at 11:44 PM, Javier Herrero jherr...@hvsistemas.es wrote:
Hello,
Javier Serrano can confirm it for sure, but I think that the article with
the OPERA results is based on data from 2009 to 2011, not from data taken
the previous day :)
Exactly. OPERA first published a
On Sat, 17 Mar 2012 06:13:28 -0700
gary li...@lazygranch.com wrote:
On 3/17/2012 5:44 AM, Attila Kinali wrote:
On Sat, 17 Mar 2012 10:15:17 +
Poul-Henning Kampp...@phk.freebsd.dk wrote:
Either you need to characterize the exact behaviour of your filter
and build the necessary
Dear Poul-Henning,
My only argument against your versatile and well-performing solution is
that it is a little bit overkill.
As if running a handfull precision oscillators just for fun isn't
overkill also ? :-)
I don't know -- are there any limits for the fun in a time-nut sense? :-)
I hope
I've designed filters for datacom chips. I know filtering. My point is
the original author is making some assumptions in the design which are
not stated.
Yes, my fault, I didn't write it properly, so by a ferrite rod in
context of DCF/WWVB reception, I meand a ferrite antenna in an LC tuned
Any filter's group delay can be equalized by all pass filters.
Delay builds up at the filter corner. Since everything in the real world is
causal, you add delay outside that corner frequency but in the passband to
equalize it. This is to say, you can't remove delay, but just add it to
flatten
Which basically matched my assumption. If the inductor is loaded, you
have a narrowband filter. So again, this does not imply that a ferrite
rod antenna per se has phase distortion. It is the LC filter than
effects the group delay.
On 3/17/2012 6:19 AM, Marek Peca wrote:
Hello, gary,
I
Yes, in order to equalize group delay, you need to know what to
equalize. But with an educated guess as to the system response, he could
get close.
All this said, in 2012, I would rather the amplifier be simple gain, the
inductor not loaded with capacitance and the filtering done past the
Which basically matched my assumption. If the inductor is loaded, you have a
narrowband filter. So again, this does not imply that a ferrite rod antenna
per se has phase distortion. It is the LC filter than effects the group
delay.
Yes, exactly. Excuse my loose speech before not explicitly
LPFRS from fluke.l? OK, then open it up and clean it, the LPFRS from
fluke.l suffers from high humidity/water immersion and usually are very
rusty inside. I have received one that was very bad but after cleaning with
tetrachloroethylene (translated with google) it is working properly, maybe
it
Hi
The problem with delay compensation in a Time Nut environment is that to do it
you add delay. Your all pass network adds enough delay to the fast part of
the passband to make it come out the same as the slow part. In real circuits
you inevitably add some delay everywhere with the all pass,
Yes, in order to equalize group delay, you need to know what to equalize. But
with an educated guess as to the system response, he could get close.
All this said, in 2012, I would rather the amplifier be simple gain, the
inductor not loaded with capacitance and the filtering done past the
I think the tempco of the ferrite is more significant than drift in the
analog filter. Of course this again implies the better design is to not
load the inductor with a cap, i.e. stay broadband, and then just filter
post the preamp.
The open circuit voltage will be lower without the resonant
Wow, no limits on the reverse engineering capabilities of this group...
amazing, now where is Elio? He must be interested in this. [I have no
FE5680A but followed the heavy posting about it, I prefer the LPFRS Rb]
On Sat, Mar 17, 2012 at 2:12 PM, J. L. Trantham jlt...@att.net wrote:
Rich,
I
OK, thank you for the information.
On Sat, Mar 17, 2012 at 2:21 PM, Javier Serrano
javier.serrano.par...@gmail.com wrote:
On Fri, Mar 16, 2012 at 11:44 PM, Javier Herrero jherr...@hvsistemas.es
wrote:
Hello,
Javier Serrano can confirm it for sure, but I think that the article with
the
Hi
If it is water immersion damage, wash it in soap and water. Then rinse it in
hot deionized water (above 10 mega ohms if you can get it). After that bake it
at 80C with good air flow for 24 hours. It still may rust, but most of the
guck from the water will be gone.
I once spent a lot of
I think the tempco of the ferrite is more significant than drift in the
analog filter.
Perhaps I was unclear in this as well. I do not use nor plan to use any
other filter than the (ferrite-L)-C resonant circuit itself. So, yes, the
tempco of the ferrite makes its coefficients variation.
Some years ago, I bought some original IBM memory for a Thinkpad laptop.
The stuff physically fit, but shorted out when installed, because the
package profile was different.
I complained to eBay and spent a bunch of money on Express Mail, etc.
I got NOTHING.
Conclusion: eBay protections are
That would be 36ns group delay variation if I did the math correctly.
However, what material are you using for the ferrite? The material can
have a significant tempco.
On 3/17/2012 7:17 AM, Marek Peca wrote:
However, for f0=77.5kHz and B=1kHz, the LC circuit with Q=40 gives phase
error
That would be 36ns group delay variation if I did the math correctly.
OK
And in article P. Hetzel: Time dissemination via the LF transmitter DCF77
using a pseudo-random phase-shift keying of the carrier, 2nd EFTF
Neuchatel, 1988., they conclude with timing results of about 2..10e-6 s
RMS
Yes, correct. The problem is that I have no deionized water nor a suitable
oven. The use of the tetrachloroethylene has simplified the procedure for
me (after all I was refunded, should the Rb fail it is not a money loss).
Anyway I'll try to locate a supply for high quality deionized water, the
http://www.fair-rite.com/newfair/materials61.htm
OK, assuming type 61, it is 0.1%/deg C. Let's go with +/- 5 degrees,
which would be for indoor use. I don't have the equation handy for a
damped LC. Certainly undamped would be worst case. f=1/(2*pi*sqrt(LC)).
When the dust settles, the
@Joe:
I'll post a link of the 25 high res x-rays of the FE-5680A board on the
company website. Gimmie a few days and I'll post the link... Also in
assembling my composite image I also included in the middle a schematic and
an optical layout taken from these three websites for guidance:
Hi Marek -
I don't know where you are in CZ. I'm on the boarder in DE near PL and
CZ. The distance to DCF77 is about 450km and if I check the amplitude
across 24h I see considerable very deep fading effects! I think it is
useless as a phase-coupled time receiver. At least in specific
You must understand the difference between deionized and destillated
water! I think often they sell deionized water of poor quality as
destillated on gas stations etc. Much like destillated as a general
synonym for the best water.
If all fails, simple rain water is very good. Wait for a heavy
Dear Henry,
I don't know where you are in CZ. I'm on the boarder in DE near PL and CZ.
my former measurement (the one at YouTube, fairly good reception, winter)
has been done under Erzgebirge, Teplice, CZ. Now I moved near Sumava
(Boehmischer Wald), so tests may follow, if I will return to
The ferrite loop antenna receives the magnetic portion of the EM wave. It
doesn't have to be a bandpass LC filter.
The Wellbrook loop antennas are one example of a broadband antenna that
receives the magnetic portion.
-Original Message-
From: ehydra ehy...@arcor.de
Sender:
gary wrote:
OK, assuming type 61, it is 0.1%/deg C.
IME, Type 78 is the usual choice for resonant antennas below 200 kHz
(tempco of initial permeability = 1.0%/deg C). I have seen Type 33
used for broadband LF/MF antennas (tempco of initial permeability =
0.1%/deg C). Type 61 is
This is interesting. I have two temex units one which works and one which has
similar issues to yours. The performance of my working one is quite good.
(If you want any specifics let me know and I can provide more details in a few
days, but I recall it is notably better than either of my
Yes, trichloroethylene is banned but not tetrachloroethylene that was used
when the first was banned.
Fluke.l has other LPFRS but beware: they are much worst than the one in the
picture, usually they go on auction so try to stay low should you ever want
to bid on one.
Actually item 29068516928 is
Rich,
Thanks. I had seen the information below. I await your posting of the
X-Ray images.
Joe
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Rich
Sent: Saturday, March 17, 2012 10:10 AM
To: time-nuts@febo.com
Subject: Re:
Marek Peca schrieb:
This was almost the only reason for ferrite rod -- simplicity and
attenuation of TVs, some LCDs, 50Hz etc.
If you make the antenna about 10x bigger you can omit the whole ferrite.
The only benefit of a ferrite loaded coil is the size of it!
In ancient time radios had flat
Check out Observations on Ferrite Rod Antennas, QEX, 2008. Type 61 works
better at low frequencies regardless of manufacturers guidelines.
-Original Message-
From: Charles P. Steinmetz charles_steinm...@lavabit.com
Sender: time-nuts-boun...@febo.com
Date: Sat, 17 Mar 2012 12:01:36
To:
Wouldn't the difference be directly proportional to the relative permeability?
If so, the difference would be more like 125, not 10, depending on core
material.
-Original Message-
From: ehydra ehy...@arcor.de
Sender: time-nuts-boun...@febo.com
Date: Sat, 17 Mar 2012 21:22:17
To:
In the end every antenna receives the EM wave! The EM-wave is the far
field. The antenna works in the near field where a dominant component
can be the E or M. That depends on the antenna. Between the near and the
far field the field is converted and local Z0 highly complicated.
As far as I know
Hi:
The material permeability gets reduced to effective permeability depending on the rod length / diameter radio (you would
like it to be = 100) to realize the material permeability).
For example: http://www.magneticsgroup.com/pdf/erods.pdf
More on ferrite loop sticks at:
No, there is a geometric saturation. You can't use the better
permeability in reality.
The optimum length to width relation is about 6 to 10 for ferrite rods.
Here is a diagram:
http://ehydra.dyndns.info/NG/time-nuts/Pettengill%20002.jpg
This is one of the classics in my link list:
In message 4f64f279.4040...@arcor.de, ehydra writes:
Marek Peca schrieb:
This was almost the only reason for ferrite rod -- simplicity and
attenuation of TVs, some LCDs, 50Hz etc.
If you make the antenna about 10x bigger you can omit the whole ferrite.
I have used two antennas, an unloade
I wonder if a GPSDO could be built around these chips.
Original Message
Subject:Maxim EE-Mail #12.11 - March 17, 2012
Date: Sat, 17 Mar 2012 10:52:26 -0700
From: Maxim EE-Mail maxim-eemail-notif...@blast.maxim-ic.com
Reply-To:
On Sat, 17 Mar 2012 15:40:27 -0700
Chuck Forsberg WA7KGX N2469R c...@omen.com wrote:
I wonder if a GPSDO could be built around these chips.
Sure, the MAX2769 is a standard GPS L1 frontend with integrated PLL,
quadrature modulators, AGC and 2bit ADCs. Nothing too fancy, but
nice and neatly
On 03/17/2012 11:40 PM, Chuck Forsberg WA7KGX N2469R wrote:
I wonder if a GPSDO could be built around these chips.
Locking it up to a 10 MHz seems doable, you need to use the fractional
division, but you can make it spot on if my back-of-the-envelope
analysis is correct.
You will have to
Since you guys know about and use this stuff, what can anyone tell me
about a Rockland 5110-37 programmable synthesizer? All I can find on
the net are references to a 5110-06, which is supposed to go up to 2
MHz. It obviously is programed via a large Amphenol connector on the
back. The are no
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