Re: [time-nuts] Three-cornered hat on timelab?

-GPSDOs/info From: Bob kb8tq <kb...@n1k.org> To: Bob Stewart <b...@evoria.net> Cc: Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Wednesday, May 3, 2017 11:11 AM Subject: Re: [time-nuts] Three-cornered hat on timelab? Hi If you convert

[time-nuts] 5370 problems, was Re: Three-cornered hat on timelab?

ay. Just use that OEM board, and your TIC, and your PRS-45A. Collect sawtooth data too. You should get down to 2 or 3 ns RMS. /tvb ----- Original Message - From: "Bob Stewart" <b...@evoria.net> To: "Discussion of Precise Time and Frequency Measurement" <time-nuts

Re: [time-nuts] Three-cornered hat on timelab?

From: Bob kb8tq <kb...@n1k.org> To: Bob Stewart <b...@evoria.net> Cc: Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Wednesday, May 3, 2017 10:48 AM Subject: Re: [time-nuts] Three-cornered hat on timelab? Hi Dump it to a csv file and do

Re: [time-nuts] Three-cornered hat on timelab?

Hi Bob, What I should have asked is this: "how do I get that from a Timelab dataset?"    Bob From: Bob kb8tq <kb...@n1k.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Cc: Tom Van Baak

Re: [time-nuts] Three-cornered hat on timelab?

't require buying expensive gear? My first suggestion is for you run a standalone GPS timing receiver like a M12+T or ublox-6. Put all your GPSDO away. Just use that OEM board, and your TIC, and your PRS-45A. Collect sawtooth data too. You should get down to 2 or 3 ns RMS. /tvb ----- Original

Re: [time-nuts] Three-cornered hat on timelab?

you're using.  I've had good luck with the Trimble 34310-Ts that are about $20 each depending on the vendor. Bob  From: Jim Harman <j99har...@gmail.com> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent:

Re: [time-nuts] Three-cornered hat on timelab?

was good.  Maybe in another 5 years the sunspots will be back up and I can see the comparison to now. Bob From: Magnus Danielson <mag...@rubidium.se> To: Bob Stewart <b...@evoria.net>; Discussion of Precise Time and Frequency Measurement <time-nuts@febo.com> Cc: mag...

Re: [time-nuts] TAPR Oncore M12+ kit

Hi Bob, It may be because the process of cutting the boards apart is not part of the board milling process.  Yes, cutting holes in boards for through-hole parts is part of the business - round holes.  The fab house for OSHPark won't make oval holes.  They won't overlap two holes, either, nor

Re: [time-nuts] Three-cornered hat on timelab?

From: Bob kb8tq <kb...@n1k.org> To: Bob Stewart <b...@evoria.net> Cc: Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Thursday, April 27, 2017 4:17 PM Subject: Re: [time-nuts] Three-cornered hat on timelab? Hi Dig into spac

Re: [time-nuts] Three-cornered hat on timelab?

From: jimlux <jim...@earthlink.net> To: time-nuts@febo.com Sent: Thursday, April 27, 2017 5:03 PM Subject: Re: [time-nuts] Three-cornered hat on timelab? On 4/27/17 12:10 PM, Bob Stewart wrote: > Hi Bob, > said: > "You have roughly 25 ns p-p in the data you show.&quo

Re: [time-nuts] Three-cornered hat on timelab?

robably increasing as the value gets lower. Not trying to crucify you with your own words, Bob.  Like many of the time-nuts who don't post, I'm just trying to make some sense of this in terms I can deal with. Bob From: Bob kb8tq <kb...@n1k.org> To: Bob Stewart <b...@evoria.net&g

Re: [time-nuts] Three-cornered hat on timelab?

to happen? Bob - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Magnus Danielson <mag...@rubidium.dyndns.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency

Re: [time-nuts] Three-cornered hat on timelab?

Hi Magnus, Today I started a long run against my PRS-45A.  Maybe this time I won't have a power outage.  I'll see what it tells me in a few days. Bob  From: Magnus Danielson <mag...@rubidium.dyndns.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time a

Re: [time-nuts] Three-cornered hat on timelab?

ges/sidereal/14years.htm http://leapsecond.com/pages/sidereal/sv.htm http://leapsecond.com/pages/gps-orbit/ - Original Message ----- From: "Bob Stewart" <b...@evoria.net> To: "Bob kb8tq" <kb...@n1k.org>; "Discussion of Precise Time and Frequency Measure

Re: [time-nuts] Three-cornered hat on timelab?

Hi Bob, OK, thanks.  I've kicked off a 7 day run of a GFS against the PRS-45A.  That should be long enough to separate out the GFS from the PRS' drift direction from the ionosphere. Bob  From: Bob kb8tq <kb...@n1k.org> To: Bob Stewart <b...@evoria.net> Cc: Discussion of

Re: [time-nuts] Three-cornered hat on timelab?

and Bruce and others have spoken about.  This bothers me a lot.  Could it be my location here in Houston?  Could it be the Ublox LEA-6T compared to the much older Motorola in the KS? Bob  From: Bob kb8tq <kb...@n1k.org> To: Bob Stewart <b...@evoria.net> Cc: Discussion of

Re: [time-nuts] Three-cornered hat on timelab?

be great! Bob  From: Bob kb8tq <kb...@n1k.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Cc: John Miles <j...@miles.io> Sent: Thursday, April 13, 2017 7:19 PM Subject: Re: [time-nuts] Three-cornere

Re: [time-nuts] Three-cornered hat on timelab?

e consistent with the source labels you apply.  I would use frequency-count mode to simplify things, at least at first.  This is already a very challenging measurement for all the reasons mentioned. -- john, KE5FX Miles Design LLC From: Bob Stewart [mailto:b...@evoria.net] Sent: Thursday, Ap

Re: [time-nuts] Three-cornered hat on timelab?

Hi John, Thanks!  With lesser equipment, such as the 5370A, would longer runs be better?  I used a set of 1 hr runs and the result wasn't quite what I had expected.  However, it may be that I had mislabeled the files, and thus got the sources confused.  Of course, it may be that the ionospheric

[time-nuts] Three-cornered hat on timelab?

It was mentioned that Timelab can do a three-cornered hat.  I can't find it.  Is this something that can only be done with multiple Timepods connected, or is there an option that I'm missing?  Or is there some other tool that needs to be used?  For the record, I want to create the 3c-hat from

[time-nuts] Timelab file needed

Does anyone have a timelab file for a KS-24361?  My KS has a much worse 1s ADEV (and on down the line) than I would have expected, and I'd like to see what others are getting. Bob AE6RV.com GFS GPSDO list:

Re: [time-nuts] Timelab, GPIB-USB-B in a VM

I don't know how they're done in VMWare, but in VirtualBox, you have to setup the USB configuration for the VM before you start it.  You just click the machine, settings, then USB, then add a device, then select from what's available.  Which means you have to have it plugged in and enumerated

[time-nuts] Timelab file wanted

have one, could you send me a copy off-list? thanks, Bob Stewart ---   bob at evoria dot net   - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info ___ time-nuts mailing

Re: [time-nuts] time-nuts equipment verification from scratch (was: WTB: GPSDO)

I would say that the price for a home-built time-nuts quality GPSDO is going to be significantly greater than $200.  Yes, if you are making them for sale, eventually the unit cost will get down there.  But to build one single good GPSDO, you're going to throw away a lot of prototypes on the way

Re: [time-nuts] ADEV query Timelab and TICC

These look a lot like the 25ns pops I was getting when I first started generating the 1PPS output from the PIC.  In my case, the PIC uses a PLL to multiply the external clock from 10MHz to 80MHz, which is then  divided to 40MHz and used as an instruction clock.  This gave an occasional early or

Re: [time-nuts] Cs standard stability

<bruce.griffi...@xtra.co.nz> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Saturday, March 4, 2017 7:14 PM Subject: Re: [time-nuts] Cs standard stability BobYou should to use the same measurement bandwidth w

Re: [time-nuts] Cs standard stability

.nz> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Saturday, March 4, 2017 6:03 PM Subject: Re: [time-nuts] Cs standard stability BobWe are certainly not off track.The phase noise of the GPSDO affects the trig

Re: [time-nuts] Cs standard stability

tracks what is to be expected when run on a good 5370, isn't it? Bob From: Bruce Griffiths <bruce.griffi...@xtra.co.nz> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Saturday, March 4, 2017 5:22 PM

Re: [time-nuts] Cs standard stability

From: Bruce Griffiths <bruce.griffi...@xtra.co.nz> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Saturday, March 4, 2017 4:28 PM Subject: Re: [time-nuts] Cs standard stability Bob Your reasoning appe

Re: [time-nuts] Cs standard stability

anything more than that.  Correct? Bob From: Bruce Griffiths <bruce.griffi...@xtra.co.nz> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Saturday, March 4, 2017 3:44 AM Subject: Re: [time-nuts] Cs

[time-nuts] Cs standard stability

I hooked up my PRS-45A yesterday, just to do some ADEV comparisons with my GPSDO.  Unfortunately, the GPSDO seems to be better by almost two points at all tau as measured on my HP 5370A and plotted by Timelab.  So, can I infer from that that the OCXO in the PRS has a problem, or could it be

Re: [time-nuts] Timelab question

From: Andrew Rodland <and...@cleverdomain.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Friday, February 24, 2017 12:18 AM Subject: Re: [time-nuts] Timelab question On Tue, Feb 21, 2017 at 5:26

Re: [time-nuts] TTimelab question

Hi John, I have to agree with you about enclosures.  They make the difference between a DIY unit and a nice commercial unit, but they are very expensive.  The enclosures I use are about $20 each from Mouser.  But the end panels are another $20 each: milled front and back.  So, that's $60 per

Re: [time-nuts] Timelab question

.  I've pretty much given up on it. Bob  From: John Miles <j...@miles.io> To: 'Bob Stewart' <b...@evoria.net>; 'Discussion of precise time and frequency measurement' <time-nuts@febo.com> Sent: Tuesday, February 21, 2017 3:56 PM Subject: RE: [time-nuts] Timelab questi

Re: [time-nuts] advice

there; whether it's time or something else. Bob Stewart (Not a physicist)  From: Rhoderick Beery <rjbe...@gmail.com> To: time-nuts@febo.com Sent: Tuesday, February 21, 2017 11:13 AM Subject: [time-nuts] advice Greetings Time-Nuts! I'm a physics theorist interested in perf

Re: [time-nuts] Timelab question

John, I apologize.  I was mistaken in my question.  Under wine it behaves poorly, but that's to be expected.  Under XP in a Virtual box, it works as you say.  The same in a real Win 10 box.  The problem is actually that I was expecting the "No" box to be checked, and to require the user to

[time-nuts] Timelab question

Is there a way to change the escape key in Timelab so that it doesn't default to "yes"?  I love Timelab, but this is driving me nuts.  I hit the escape key and it asks me if I really want to exit.  No, I don't!  So, I hit the escape key and yes, it does exit. Bob

Re: [time-nuts] Vintage Frequency Measurement

In fact, I used a similar method for adjusting the AOR DDS-2A synthesizer on my Collins rig.  I tune an AM radio to WWV.  And I tun the DDS-2A / Collins to the same signal only using SSB.  Then when WWV is sending the tone modulated signal, I tune the DDS-2A calibration control to eliminate the

Re: [time-nuts] Sub-ps delay line

Since you need a set-and-forget type of solution, could you use a wide trace on your board and laser etch/mill it to set your delay, similar to the way film resistors are trimmed?  IOW, add length by turning the wide trace into a zig-zag. Bob 

Re: [time-nuts] What interrupts aging?

Hi John, My experience, which is far from scientific, is that any disturbance to the Trimbles I use is like a slap in the face.  It can be just a momentary power loss or a large change in the EFC.  After either of these events, it goes into some period of retrace before it settles back down. 

Re: [time-nuts] Power Problems Lucent KS-24361, L101 & L102

To add in some small manner to what Bob Camp said: IIRC, the input is polarity protected by a diode or two.  I think the input to the brick is floated; i.e. neither of the two power leads is connected to ground.  The brick can be disassembled, if you're careful.  The components, except for the

Re: [time-nuts] distribution amp question + hp 59309A

Walter said: "Also on an unrelated topic, I found an HP 59309A HPIB clock on a forgotten shelf  and looked at it, and was surprised to see such a poor primary time standard oscillator inside, just a 1Mhz crystal using a cmos buffer oscillator. It can accept an external standard, but it did feel

Re: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year

I used KICAD for my GPSDO.  I've never used Eagle, so I don't know what differences there are.  I had used ExpressPCB, so it did take some getting used to.  Even at my early entry-level stage, a number of components supplied with the program were unusable.  This was mainly due to the size of

Re: [time-nuts] General questions about making measurements with time interval counter.

ter two display the number of terms used in the calculation, which partly addresses your question. /tvb - Original Message - From: "Scott Stobbe" <scott.j.sto...@gmail.com> To: "Bob Stewart" <b...@evoria.net>; "Discussion of precise time and frequen

Re: [time-nuts] General questions about making measurements with time interval counter.

.  Bob From: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Thursday, January 12, 2017 2:38 PM Subject: Re: [time-nuts] General questions about making measurements with time

Re: [time-nuts] General questions about making measurements with time interval counter.

th someone. Bob - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <t

Re: [time-nuts] General questions about making measurements with time interval counter.

Hi Bob, Normally I see somewhere between 2E-11 and 4E-11 at 1S tau on my 5370A, as in the blue trace on the attached plot.  Am I misunderstanding your meaning?  Granted, I am clocking the 5370A with a GPSDO, but I believe I see about the same thing with the HP10811.  This test was 1PPS vs 1PPS

Re: [time-nuts] hm H Maser

This may be a dumb question, but how much of an H Maser's advantage over a Cs Standard, for us mere mortal time-nuts, is down to the output oscillator it uses, rather than the reference source (H MASER or Cs beam)? Bob From: Dr. David Kirkby (Kirkby Microwave Ltd)

Re: [time-nuts] Something odd - ionosphere?

storms on Jan. 8th asbright auroras > <http://spaceweathergallery.com/aurora_gallery.htm>flicker around the > Arctic Circle. > > http://spaceweather.com/ for further details > > cheers, Graham ve3gtc > > On 2017-01-08 20:48, Bob Stewart wrote: >> This mo

Re: [time-nuts] Something odd - ionosphere?

geomagnetic storms on Jan. 8th asbright auroras <http://spaceweathergallery.com/aurora_gallery.htm>flicker around the Arctic Circle. http://spaceweather.com/ for further details cheers, Graham ve3gtc On 2017-01-08 20:48, Bob Stewart wrote: > This morning at about 0400 CST and again at

[time-nuts] Something odd - ionosphere?

This morning at about 0400 CST and again at more or less 0800CST, I noticed a number of large phase excursions on one of the GPSDOs I'm testing.  It also happened the day before but I didn't notice the time.  I am comparing the 1PPS from two separate units on a 5370.  On the one unit I was

[time-nuts] Tom's PICDiv?

Hi all, I was wondering if anyone makes a nice, complete unit from one of Tom's PICDivs; preferably with an external 10MHz input, a 10MHz output and a 1PPS output?  It would be nice if it also accepted a 1PPS in to sync the PIC's output to an external 1PPS source, but that's not a necessity. 

[time-nuts] Leap second on LEA-6T

Here's the leap second as my GPSDOs saw it.  But, I'm still in the dark about how Ublox does their pending leap second notification.  There are very few messages that have any leap second info, and I had hoped that the aiding message AID-HUI would do something at the leap second.  But, the

Re: [time-nuts] Anyone (ideally in the UK) got a spare rotary knob for the 5370B TI counter?

If you can touch the heat sink for 2 seconds, you're made of sterner stuff than I am!  They run very hot.  It's a good idea to get a GPIB extender so your GPIB cable can clear the heat sink.  Somebody, can't remember who, worked up a nice looking conversion to a pair of switching supplies.  I

Re: [time-nuts] u-blox timing modules

Hi John, Could you tell me why one would use choose an LEA-M8F over an LEA-M8T? Bob - AE6RV  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: John Haine To:

Re: [time-nuts] 1PPS users?

/groups/GFS-GPSDOs/info From: Scott Stobbe <scott.j.sto...@gmail.com> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Sunday, December 18, 2016 8:22 PM Subject: Re: [time-nuts] 1PPS users? Part of the

Re: [time-nuts] 1PPS users?

:56 PM Subject: Re: [time-nuts] 1PPS users? On 12/18/16 3:16 PM, Bob Stewart wrote: > One thing I've never really understood is who actually uses the high-quality > 1PPS output from a GPSDO.  I have spent a lot of time, effort, and money on > developing my GPSDO without a w

[time-nuts] 1PPS users?

One thing I've never really understood is who actually uses the high-quality 1PPS output from a GPSDO.  I have spent a lot of time, effort, and money on developing my GPSDO without a whole of thought to the user base.  It was just a quest for the best result I could obtain with a particular

Re: [time-nuts] Lady Heather for homebrew GPSDO

Mark, I haven't had the time to look at the LH code yet, but is there a sort of natural interface that would most easily fit?  I'm speaking about both sides of the conversation: receiving data streams and sending commands.  It seems a bit strange to me that NMEA would be the preferred type of

Re: [time-nuts] Lady Heather for homebrew GPSDO

Hi Jim, A couple of years ago, I asked the group if there was a standard UI that I should use for the GPSDO that I was developing.  Everyone said no, just do what works.  I don't think it occurred to anyone, certainly not to me, just how big a role that LH plays in the world of GPSDOs.  So,

Re: [time-nuts] OT: ExpressPCB (cross-post from volts-nuts)

I built my first set of boards with ExpressPCB, but they get expensive quickly if you want to make something that's not in their special form factor.  I use KICAD and OshPark.com to make my boards (there are other board makers).  I just ordered some boards that are .7" x .63" that cost $8.40

Re: [time-nuts] Vintage Quartz Crystal Manufacturing

To me, these devices look like they may have a quartz crystal at the bottom, and spring and screw adjuster on the top. Bob - AE6RV From: Paul Berger To: Discussion of precise time and frequency measurement Sent: Saturday, November 26, 2016 10:47

[time-nuts] TDOP impact on accuracy of receiver's 1PPS

I can't help but notice that there is an impact on the measured phase error every time the TDOP reported by the LEA-6T changes.  What I don't know is how to characterize the impact.  Is the impact more of a change in the error band, rather than a bias in one direction or the other?  Would a

Re: [time-nuts] Thermal impact on OCXO

Hi Bob, said:  "Most (> 99%) OCXO’s are made to custom specs for large OEM’s. The sort consists of “ship these” and “send these to the crusher”.  Needless to say, the emphasis is on a process that throws out as few as possible. " We've seen a serious improvement in manufacturing yields at close

Re: [time-nuts] precision timing pulse

Just a short comment on getting a PIC up and running.  Microchip have come out with a number of tools, especially their "Configurator" software that will get you started pretty quickly.  And there is a long list of example programs on microchip's website for simple programs that do things like

Re: [time-nuts] quartz drift rates, linear or log

So, are you measuring OCXO stability or EFC stability? Bob  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Tom Van Baak To: Discussion of precise time and frequency

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

, then, yes, it's an easy job to make the pulsewidth very stable at whatever value you choose. Bob  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Adrian Godwin <artgod...@gmail.com> To: Bob S

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

o do precise time with a high level language. /tvb - Original Message - From: "Bob Stewart" <b...@evoria.net> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Wednesday, November 09, 2016 9:30 AM Subject: Re: [time-nuts]

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

I'd like to comment on the idea of measuring the width of the pulse.  My experience with creating the 1PPS from an interrupt is that it's fairly straightforward how to do the set interrupt:  The interrupt happens, you execute one, maybe two instructions to raise the output pin, and you leave

Re: [time-nuts] Thermal impact on OCXO

/GFS-GPSDOs/info From: Scott Stobbe <scott.j.sto...@gmail.com> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Monday, November 7, 2016 2:48 PM Subject: Re: [time-nuts] Thermal impact on OCXO Another n

Re: [time-nuts] Thermal impact on OCXO

test lead to the EFC (breaking a trace in the process) there was enough off time to thoroughly insult the OCXO. Bob - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Bob Camp <kb...@n1k.o

Re: [time-nuts] Thermal impact on OCXO

: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net> Cc: Discussion of Precise Time and Frequency Measurement <time-nuts@febo.com> Sent: Monday, November 7, 2016 11:54 AM Subject: Re: [time-nuts] Thermal impact on OCXO Hi I would suggest you read the papers

Re: [time-nuts] Thermal impact on OCXO

/groups/GFS-GPSDOs/info From: Scott Stobbe <scott.j.sto...@gmail.com> To: Bob Camp <kb...@n1k.org> Cc: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Monday, November 7, 2016 9:34 AM Subject: Re: [time-nuts

Re: [time-nuts] Thermal impact on OCXO

Hi guys, First of all, thanks for the additional responses.  I was a bit angry and rude yesterday, and I figured this thread was over.  Thanks for staying with me. I haven't had time to look over the data etc in your responses.  I'll do that and get back to the list if appropriate. I spoke to

Re: [time-nuts] Thermal impact on OCXO

divider; which is a 15K/16K divider. Bob  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net> Cc: Discussion of Precise Time a

Re: [time-nuts] Thermal impact on OCXO

-GPSDOs/info From: Scott Stobbe <scott.j.sto...@gmail.com> To: Bob Stewart <b...@evoria.net> Cc: Discussion of Precise Time and Frequency Measurement <time-nuts@febo.com> Sent: Saturday, November 5, 2016 9:19 PM Subject: Re: [time-nuts] Thermal impact on OCXO If your

Re: [time-nuts] Thermal impact on OCXO

groups/GFS-GPSDOs/info From: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net> Sent: Saturday, November 5, 2016 8:46 PM Subject: Re: [time-nuts] Thermal impact on OCXO Hi My experience is that the aging on these oscillators is so far below a number of issues tha

Re: [time-nuts] Thermal impact on OCXO

From: Scott Stobbe <scott.j.sto...@gmail.com> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Saturday, November 5, 2016 8:38 PM Subject: Re: [time-nuts] Thermal impact on OCXO I think that's a nice p

Re: [time-nuts] Thermal impact on OCXO

B between the OCXO ground pin and “ground” from grabbing the OCXO is harder to measure, but also pretty typical. It sums right into the EFC line. It’s not a rabbit hole so much as the details of the design at the level you have chosen to look at. Bob > On Nov 5, 2016, at 8:10 PM, Bob Stewart &l

Re: [time-nuts] Thermal impact on OCXO

pact on OCXO ...with a 20bit DAC, a suitable voltage reference for that DAC and an HP3458... On Sun, Nov 6, 2016 at 12:39 AM, Bob Stewart <b...@evoria.net> wrote: > Hi Hal, > > With a 20 bit DAC, even a small aging rate is going to show up.  I'll let the > one GPSDO cook for a mon

Re: [time-nuts] Thermal impact on OCXO

GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Hal Murray <hmur...@megapathdsl.net> To: Bob Stewart <b...@evoria.net> Cc: Hal Murray <hmur...@megapathdsl.net> Sent: Saturday, November 5, 2016 6:23 PM Subject: Re: [time-nuts] Thermal impact on OCXO >

Re: [time-nuts] I love the smell of tantalum in the morning

Hi John, I've never used the hot tweezers.  I'm going to have to look into them.  Normally, for desoldering, I use a narrower nozzle with an elevated temperature - usually between 280C and 350C.  That blows the part completely off the pads just as soon as the solder flows, with little impact

Re: [time-nuts] I love the smell of tantalum in the morning

Hi Tom, Personally, I wouldn't touch this without a hot air gun.  I don't know what your budget is.  What I consider reasonable may be an order of magnitude smaller than for you.  So, I use a generically labeled 852D+ rework combo.  It has both solder pencil and hot air gun.  There are better

Re: [time-nuts] Thermal impact on OCXO

Oh dear.  I attached the wrong file.  Here's the correct one.  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info ___ time-nuts mailing list -- time-nuts@febo.com

Re: [time-nuts] Thermal impact on OCXO

r question?  If not, let me know what's missing. Bob - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Hal Murray <hmur...@megapathdsl.net> To: Bob Stewart <b...@evoria.net>; Discussion of prec

Re: [time-nuts] Thermal impact on OCXO

 - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com>

Re: [time-nuts] Thermal impact on OCXO

there. Bob - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Scott Stobbe <scott.j.sto...@gmail.com> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measuremen

Re: [time-nuts] Thermal impact on OCXO

OK, never mind.  I see the obvious.  Phase changes faster at a higher frequency than it does at a lower frequency. Bob  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Bob Stewart &l

[time-nuts] Thermal impact on OCXO

In the general case, is the impact of changing the ambient temperature around an OCXO from, say, 40C to 41C the same as changing it from 41C to 40C all else being equal?  IOW, if I somehow have the same temperature ramp over the same time period in both directions, will I wind up with the same

Re: [time-nuts] 12.6GhZ Yb clock - was Cs tube pics

m your synthesis chain to the 12.6 GHz hyperfine transition > in Yb is not continuous. There's a measurement sequence of state > preparation etc that means you only get an error measurement every 10 to > 100 s. so you need a good flywheel in between. > > Cheers > Michael > > On

Re: [time-nuts] 12.6GhZ Yb clock - was Cs tube pics

Hi Michael, I've got a dumb question about the need for a really good flywheel oscillator for the 12.6Ghz Yb clock:  What is the signal that is locking that oscillator?  Is it a 1PPS, or is it something in the RF domain, such as 10MHz or higher? I still hope to make a modern version of the old

Re: [time-nuts] theoretical Allan Variance question

Perfect?  I can't tell you that.  But I can tell you that the 1s ADEV that I can measure is limited to the stability of the reference oscillator, and to the resolution and stability of the measuring device.  For example, I have an HP 5370A TIC.  It's good to about +/- 20ps.  So, that's the

Re: [time-nuts] Opening an Isotemp OCXO

>From experience, I can tell you that you can't always depend on the seller >when it comes to how to feed your new OCXO.  For instance, the seller of the >Trimble 65256 insisted that it took 12V.  So, that's what I used, and all the >magic smoke came tumbling out. Bob   From: Peter

Re: [time-nuts] Opening an Isotemp OCXO

Hi Bob, Can't the OCXOs be characterized pretty closely by someone with the right tools and staff?  I don't have a big sample to speak from, but the Trimbles I use only have a couple of ceramic coated pieces, and those can be exposed down to the die by hand and then characterized, can't they? 

Re: [time-nuts] Aging and Thermal Correction in Holdover

From: Attila Kinali <att...@kinali.ch> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Thursday, October 27, 2016 1:45 PM Subject: Re: [time-nuts] Aging and Thermal Correction in Holdover On Thu, 27 Oct 2016 16:13:06 +0000 (UTC) Bo

Re: [time-nuts] Aging and Thermal Correction in Holdover

Kinali <att...@kinali.ch> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Wednesday, October 26, 2016 1:28 PM Subject: Re: [time-nuts] Aging and Thermal Correction in Holdover On Wed, 26 Oct 2016 17:01:

Re: [time-nuts] Temp/Humidity control systems?

Hi John, Have you looked into walk-in humidors to see if there are any ideas there that you could use?  Yeah, those use high levels of humidity, but there might be something in common with your needs. Bob  - AE6RV.com GFS GPSDO

[time-nuts] Aging and Thermal Correction in Holdover

I'm working on the Aging and Thermal Correction algorithms in my GPSDO.  At this point, it's pretty simple: For aging, every X seconds I either increment or decrement the DAC value by 1 as determined by the unit's performance history.  For thermal, every X seconds (user settable) I check to see

Re: [time-nuts] For those that insist on using switching power supplies

I've actually got 10 or 12 of those sitting in a box.  I got them because of the "grounded" power header.  The units I got used the 3-pin header but only had a 2-wire plug.  So, something seemed wrong and I opened it up.  I noticed the same thing: that the non-soldered ground pin went nowhere. 

Re: [time-nuts] TimeLab

AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Sunday, October 9, 2016 11:50 AM Subject: Re

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