Re: [time-nuts] Fwd: HP 53131A Power Off Mod

*Important Update:* due to a mistake in my thinking, I had to upgrade the fuse I added to a 220V, 3A model to match the fuses on the internal switching power supply. My original plans were to mount the fuse on the power supply PCB and use it only to fuse the small power adapter used to power the r

Re: [time-nuts] Fwd: HP 53131A Power Off Mod

The PCBs and Parts arrived and, after putting everything together and testing it, it all seems to work fine. And, to document everything, I've put up a web page at my web site that describes the mod and how to implement it: https://sites.google.com/site/wayneholder/hp-53131a-power-off-mod I ha

Re: [time-nuts] Fwd: HP 53131A Power Off Mod

Thanks! I plan to publish the Gerber files and make them available to fab at OSH Park as part of an a article I'll put up on my webpage at https://sites.google.com/site/wayneholder/ but I want to make sure everything works as expected before I do. I'm still waiting for parts and the PCBs to show

Re: [time-nuts] Fwd: HP 53131A Power Off Mod

Hi Wayne, Congrats on a nice simple mod ! I have both a 53131 and 181 in need of these :) Can you share the gerbers for your PCBs and then I can cut them out on my mill. I could probably make a few for any interested Australians, to save on cross pond postage. thanks Tim On 8/05/2018 9:

[time-nuts] Fwd: quartz / liquid nitrogen

at low temperatures bipolar devices will have reduced gain 73 KJ6UHN Alex Forwarded Message Subject:[time-nuts] quartz / liquid nitrogen Date: Mon, 2 Apr 2018 12:46:26 -0700 From: Tom Van Baak Reply-To: Tom Van Baak , Discussion of precise time and frequency

[time-nuts] Fwd: [New post] New Part Day: ATMegas With Programmable Logic

nutters might find this of interest. Don Original Message SUBJECT: [New post] New Part Day: ATMegas With Programmable Logic DATE: 2018-03-02 05:00 FROM: Hackaday

[time-nuts] Fwd: Cannot Command RFTGm-II-Rb / RFTGm-II-XO

@Mark - I would certainly take the latest version of Lady Heather to compile. I have already compiled and am using the Dec 2016 / v5 version of LH now, and while it receives data it does not recognize either Rb or XO devices. I did pull down RFTG.EXE, et. al., off the ko4bb.com web site. Unfortunat

Re: [time-nuts] Fwd: A talk on Atomic Clocks by Steve Jefferts NISTBoulder Wed 11/15

t" Sent: Saturday, November 11, 2017 7:50 AM Subject: [time-nuts] Fwd: A talk on Atomic Clocks by Steve Jefferts NISTBoulder Wed 11/15 For time-nuts in the Washington/Baltimore area... > > http://www.aps.org/units/maspg/ > November 2017 Event > > Date: November 15, 2017 >

[time-nuts] Fwd: A talk on Atomic Clocks by Steve Jefferts NIST Boulder Wed 11/15

For time-nuts in the Washington/Baltimore area... > > http://www.aps.org/units/maspg/ > November 2017 Event > > Date: November 15, 2017 > Speaker: Steven R. Jefferts > Topic: Primary Frequency References at NIST: Atomic Clocks > Time and Location: 1:00 p.m., with Q&A to follow in a 1st floor con

[time-nuts] Fwd: Distribution divider/amplifier for 10MHz GPSDO

Hi, > Is it safe to have RG174 coming out of the GPSDO, tapping into it with a BNC T-junction that plugs into the back of each device that needs the 10mhz input, and then terminating the strand with a 50 ohm terminator? Besides the usual signal integrity issues, remember to provide a solid earth

Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

there is no reason for an eclipse to affect time. However, working on the 1999 data made available by the German group, I had found a periodicity in the noise in one of the time series. In particular, a pattern (a peak) was repeated every 35 minutes, which was the periodicity recorded by a gravi

Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

On 8/4/17 7:22 AM, Tom Van Baak wrote: We were originally going to put a 5071A-locked beacon on three ham bands, but decided WWV and CHU would be better sources, and logistics were turning into a problem: I'm going to be doing my wideband recording from a cottage in northern Michigan. But I'm st

Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

> We were originally going to put a 5071A-locked beacon on three ham > bands, but decided WWV and CHU would be better sources, and logistics > were turning into a problem: I'm going to be doing my wideband recording > from a cottage in northern Michigan. But I'm still a time-nut, so the > rece

Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

On 8/3/17 12:10 PM, John Ackermann N8UR wrote: This is a little off-topic, but thought some of the group might be interested... so please forgive the interruption. Here's a time-nuts connection some ionosphere scientists I've been working with suggest that you sync your SDR and make it receive

Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

17 9:20 PM Subject: Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse That experiment is happening, too. Folks will be monitoring WWV and CHU in narrowband mode with the same tools they use in the frequency measuring tests. (You can't really do direct phase comparisons on

Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

ll be more useful that we could imagine. Alan G3NYK - Original Message - From: "John Ackermann N8UR" To: "Discussion of precise time and frequency measurement" Sent: Thursday, August 03, 2017 8:10 PM Subject: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

ence and electronics. If it does that it will be more useful that we could imagine. Alan G3NYK - Original Message - From: "John Ackermann N8UR" To: "Discussion of precise time and frequency measurement" Sent: Thursday, August 03, 2017 8:10 PM Subject: [time-n

[time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

This is a little off-topic, but thought some of the group might be interested... so please forgive the interruption. John Forwarded Message Subject: [hpsdr] SDR experiment for the solar eclipse Date: Thu, 3 Aug 2017 15:07:57 -0400 From: John Ackermann N8UR To: fmt-n...@yahoo

[time-nuts] Fwd: Annual Maintenance Shutdown of the MSF Service 14 - 31 August 2017

The 60KHz time signal service "MSF" in the UK is to be closed down during the day for the latter part of August for routine maintenance: Annual Maintenance Shutdown of the MSF Service The annual maintenance shutdown of the MSF service to allow

[time-nuts] Fwd: 5370B Question / help needed

I have a 5370B from ebay, it was missing a couple of boards and had a bad interpolator card. Also a bad input hybrid on the stop channel. My unit acts similar to yours, TI measurement on the 10mhz signal shows 107 ns. Frequency and Period measurement is spot on. I think it needs an alignment

[time-nuts] Fwd: Temperature sensors and quartz crystals (was: HP5061B Versus HP5071 Cesium Line Frequencies)

https://www.febo.com/pipermail/time-nuts/2017-May/105566.html I said that thermistors have been obsolete for 40 years not themocouples. (With a FEW rare exceptions) I do not consider platinum wire to be a thermistor. I own a 100 Ω platinum wire thermometer for the DVM in my 2236 Tekronix. It is

[time-nuts] Fwd: Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

From: jimlux Date: Sun, Jun 4, 2017 at 4:47 AM Subject: Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies To: time-nuts@febo.com On 6/3/17 9:56 PM, Donald E. Pauly wrote: > It was only in the early 70s that Analog Devices invented the AD590 > solid state temperature senso

[time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

I've bought dozens of them over the years and talked to crystal engineers for tens of hours. I watched them plated and tuned at a crystal filter company in Phoenix. I own Virgil Bottom's book on the subject and understood half of it. πθ°μΩω±√·Γλ WB0KVV -- Forwarded message -- F

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

In message <3ca81847-63c4-f803-994d-8e07c9973...@earthlink.net>, jimlux writes: >Modern RTDs all are 0.00385 ohm/ohm/degree at 25C. Typically, you have >a 100 ohm device (although there are Pt1000s), so it's changing 0.385 >ohm/degree. 1 part in 3000 Depending how much money you want

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

On 6/3/17 9:56 PM, Donald E. Pauly wrote: It was only in the early 70s that Analog Devices invented the AD590 solid state temperature sensor. It made thermister bridges obsolete. There is a difference between something like a platinum resistance thermometer (PRT or RTD) and a thermistor, but

[time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

You have a fundamental misunderstanding of the AT curve family. See my QBASIC plot at http://gonascent.com/papers/hp/hp5061/photos/newxtl.jpg . The commonly described AT cut is shown as the largest sine wave in the blue rectangle. The left side of the rectangle is -55°C, the center is 25° C and

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

On 6/3/17 8:26 PM, Hal Murray wrote: jim...@earthlink.net said: I guess the regen receiver must have had some gain at 1 MHz. I found an old GE datasheet that gives the ft of 0.6 MHz. (and the hfe wasn't bad, 20, at DC, probably) But you sure weren't building a 5MHz or 10 MHz oscillator wit

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

jim...@earthlink.net said: > I guess the regen receiver must have had some gain at 1 MHz. I found an old > GE datasheet that gives the ft of 0.6 MHz. (and the hfe wasn't bad, 20, at > DC, probably) > But you sure weren't building a 5MHz or 10 MHz oscillator with a 2N107 or a > CK722. Or the 2

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

On 6/3/17 2:38 PM, Poul-Henning Kamp wrote: In message , "Donald E. Pauly" writes: Electronic thermal coolers did not exist then http://www.thermoelectrics.caltech.edu/thermoelectrics/history.html I'm not sure about fancy coolers.. Yeah, people showed that the effect worked, but

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

In message , "Donald E. Pauly" writes: >Electronic thermal coolers did not exist then http://www.thermoelectrics.caltech.edu/thermoelectrics/history.html >Electronic temperature sensors did not exist either. https://en.wikipedia.org/wiki/Resistance_thermometer#History -- Poul-Henni

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

In message , jimlux writes: One final detail about TEC's which people usually don't have to worry about, is that they're not happy about switching directions. You generally end up with them mechanically tearing themselves apart if you use them for mixed cooling/heating. -- Poul-Hennin

[time-nuts] Fwd: Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

. Highest power is required at high ambient temperatures. πθ°μΩω±√·Γ WB0KVV https://www.febo.com/pipermail/time-nuts/2017-June/date.html -- Forwarded message -- From: Bruce Griffiths Date: Fri, Jun 2, 2017 at 4:34 PM Subject: Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line

[time-nuts] Fwd: HP10811 Oscillator Thermal Fuse

https://www.febo.com/pipermail/time-nuts/2017-Jun/date.html We finally got in the Panasonic thermal fuses for the HP10811 and have a few extra. They will either plug in or solder. Contact me if you need one. πθ°μΩω±√·Γλ WB0KVV -- Forwarded message -- From: Van Horn, David Date

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

Thermomechanical fatigue can significantly reduce the lifetime of Peltier devices if the ripple current flowing in the Peltier device is too high. This can become an issue with switchmode drive to a Peltier cooler. Bruce > > On 03 June 2017 at 11:02 jimlux wrote: > > On 6/2/17 2:51

[time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

https://www.febo.com/pipermail/time-nuts/2017-May/105566.html Electronic thermal coolers did not exist then so it could not be done. Electronic temperature sensors did not exist either. That crystal cut has been known since the 1940's at least. It has been neglected because of limited temperatur

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

With an AT crystal, manufacturing tolerances will likely ensure that the inflection point slope is non zero whereas the same manufacturing tolerances will merely change the turnover temperature. Its likely that a more manufacturable design will result if one operates at a turnover point (with th

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

On 6/2/17 2:51 PM, Donald E. Pauly wrote: This is an improvement of 476 to 1. You apparently have not thought thru what improvements are possible with thermal coolers/heaters. Among these is near instant warm up and greatly reduced power for thermal management. without getting into the whole

[time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

# 2 is not true. A cut has either two turning points or zero. Where both turning points exist there are two temperatures at which the temperature coefficient of frequency is zero. Cut 0 on figure 6 at https://coloradocrystal.com/applications has no turnover point. It is neither fish nor fowl.

[time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

https://www.febo.com/pipermail/time-nuts/2017-May/105566.html If we build this circuit it would be a bench model not designed to be inside a hot chassis. It would be able to lock ± 5° C of 25° C. My idea of an oven is to keep the crystal and oscillator at 25° C ±0.001 °C with 60 second warm up/c

[time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

https://www.febo.com/pipermail/time-nuts/2017-May/105500.html We recently did a partial alignment of the lock servo on our #2 HP5061B after replacing the beam tube. The previous owner had tried to fix it by turning adjustments. This made a big improvement in the lock. KB7APQ got the idea to use

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

Though I will never see a OSA 3000, It certainly sounds like a hack could be done to obtain a Cs off reference. But then when you don't actually have one you can make comments like that. Sounds nice. Regards Paul WB8TSL On Sun, May 28, 2017 at 8:20 AM, Magnus Danielson < mag...@rubidium.dyndns.org

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

Hi, On 05/28/2017 11:52 AM, "Björn Gabrielsson" wrote: So while I'm eager to see Donald's results, I question their merit. The 5061 standards already have a very convenient Cs-Off switch right on the front panel. It is there so you get the pure 10811 performance when you need it. Use it. In fac

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

> So while I'm eager to see Donald's results, I question their merit. The 5061 standards already have a very convenient Cs-Off switch right on the front panel. It is there so you get the pure 10811 performance when you need it. Use it. In fact there's lots of people run their precious 5061 in > Cs-

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

ich also helps you tailor the ADEV you want out of the instrument. /tvb - Original Message - From: "Richard (Rick) Karlquist" To: "Discussion of precise time and frequency measurement" ; "Donald E. Pauly" Sent: Saturday, May 27, 2017 5:15 PM Subject: Re: [tim

Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

On 5/27/2017 2:08 PM, Donald E. Pauly wrote: I am investigating the total redesign of the HP5061B lock system for vastly improved performance. It looks like the performance of the HP5071A can be beaten by 10 to 1 for averaging times on the order of a few seconds. πθ°μΩω±√·Γλ WB0KV That's an

[time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

Tom: The Greek letters are my pallet for common electronic letters. I transposed two items in my last post and here they are corrected. Note that the √(frequency error)=ratio of Zeeman frequencies as well as ratio of C fields. model/freq error cps/Zeeman freq kc/C field/(milliGauss) 5061A 1.59

[time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

https://www.febo.com/pipermail/time-nuts/2017-May/105298.html Those were interesting links. C field levels are a small fraction of the earth's field of 700 milliGauss. The C field winding is a few turns inside the beam tube. They are driven by several different possible currents depending upon t

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

grace of G-d, the house would have burnt down. A thermal fuse in the > transformer would have prevented several thousand dollars of damage. > That would have paid for over a thousand thermal fuses. > > πθ°μΩω±√·Γλ > WB0KVV > > Forwarded message -- > From: David G

[time-nuts] Fwd: time.gov

Be sure to post your result. Five years ago I regularly checked my Casio LED watch which was holding 0.3 seconds per week. It always worked properly. Perhaps we should report this to Trump so he can fire the head of NIST. -- Forwarded message -- From: Jerry Hancock Date: Thu, M

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

There's an excellent article out there on the web called "Low Voltage, the incompetent ignition source" I highly recommend a read. I dealt with a case like this a couple years ago. Failed fet in an H bridge caused a fault which the brick SMPS picked up as a short, and went into "hiccup" mode

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

Forwarded message -- From: David G. McGaw Date: Wed, May 10, 2017 at 8:20 PM Subject: Re: [time-nuts] Fwd: HP10811 Oscillator Thermal Fuse To: Discussion of precise time and frequency measurement I too have had a fuse open up due to a failed thermistor in a HP10811. David N1HAC

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

cussion of precise time and frequency measurement Subject: Re: [time-nuts] Fwd: HP10811 Oscillator Thermal Fuse I too have had a fuse open up due to a failed thermistor in a HP10811. David N1HAC On 5/10/17 7:43 PM, Dan Rae wrote: > As I reported the last time this subject came up, or m

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

I too have had a fuse open up due to a failed thermistor in a HP10811. David N1HAC On 5/10/17 7:43 PM, Dan Rae wrote: As I reported the last time this subject came up, or maybe the time before, the only time I had an open thermal fuse was in a 10811 that had an open thermistor. I was able to

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

kb...@n1k.org said: > The is related to safety (full time power on). As it worked out, the fuse > did not help them in that respect. The Fed’s still ruled the gear had to be > shut off at night. Could you please say more... Does that mean unplugging gear with always-on OCXOs? Or dumping the

[time-nuts] Fwd: Fwd: HP10811 Oscillator Thermal Fuse

istors in which disaster was avoided by the thermal fuse blowing. πθ°μΩω±√·Γλ WB0KVV -- Forwarded message -- From: Richard (Rick) Karlquist Date: Wed, May 10, 2017 at 5:34 PM Subject: Re: [time-nuts] Fwd: HP10811 Oscillator Thermal Fuse To: Discussion of precise time and frequency mea

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

The view from inside HP when I worked with the people who designed and built the 10811 some 35-40 years ago was that: 1. 10811 ovens rarely fail. 2. When they do fail, it is rarely because the oven runs away. I know I have never encountered a runaway. No one at HP had a "trophy" on their desk

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

As I reported the last time this subject came up, or maybe the time before, the only time I had an open thermal fuse was in a 10811 that had an open thermistor. I was able to replace that and get the OCXO working, but if the fuse had been replaced with a wire link I'm sure the entire oven woul

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

r proportion of nuisance blows. > > πθ°μΩω±√·Γλ > WB0KVV > > From: Mike Feher > Date: Tue, May 9, 2017 at 9:10 PM > Subject: Re: [time-nuts] Fwd: HP10811 Oscillator Thermal Fuse > To: Discussion of precise time and frequency measurement > > Respectfully I disag

[time-nuts] Fwd: HP10811 Oscillator Thermal Fuse

nuisance blows. πθ°μΩω±√·Γλ WB0KVV From: Mike Feher Date: Tue, May 9, 2017 at 9:10 PM Subject: Re: [time-nuts] Fwd: HP10811 Oscillator Thermal Fuse To: Discussion of precise time and frequency measurement Respectfully I disagree. I have totally shorted out numerous oscillator’s fuses with no

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

- 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> https://www.fe

[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 woul

Re: [time-nuts] Fwd: HP5061B High Ion Current/Tubes Out of Cesium

Don't forget Skips great hi-res pixs. Those pictures actually triggered a complete re-thinking for me about how C tubes actually work. Further digging and reading that set me straight. I think Poul-Henning helped me also. I doubt there are fumes in a 004. But a low flux tube there may be hope. Rega

Re: [time-nuts] Fwd: HP5061B High Ion Current/Tubes Out of Cesium

In message , "Donald E. Pauly" writes: >I think that a website should be started with the collected wisdom of >this list. I've been advocating a time-nuts wiki for some time, but I don't have time to run it myself. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.

[time-nuts] Fwd: HP5061B High Ion Current/Tubes Out of Cesium

https://www.febo.com/pipermail/time-nuts/2017-April/thread.html We did not attempt to achieve lock because we saw absolutely no beam current with the beam adjust all the way up. We were running the oven above 150° C which is more than 65° above normal oven temperatures. Cesium pressure should hav

[time-nuts] Fwd: HP5061B Peak to Valley Ratios

https://www.febo.com/pipermail/time-nuts/2017-April/104600.html Here is the plot on the Zeeman frequency data that we gathered this morning. It is close to Figure 4-43 (page 4-31) in the service manual for the HP5061B. Thanks to Jonathon for plotting this. http://gonascent.com/papers/hp/hp5061/

Re: [time-nuts] Fwd: HP5061B Ion Current

Donald, Very good and it is as I thought. No real magic a tough job. Whats good about the suspended approach is it preserves the can nicely. I have done a pry (small screw driver or xactor blade) and drip approach and it actually slightly bends the can lip out. I have never opened one of the HV sup

[time-nuts] Fwd: HP5061B Ion Current

https://www.febo.com/pipermail/time-nuts/2017-March/104374.html We continue troubleshooting our 2nd HP5061 acquisition. The 200 Meg resistor in the +3,500 V supply had gone way up in value and made it appear that the supply was half normal voltage. See the black resistor in http://gonascent.com/

[time-nuts] Fwd: Fwd: HP5061B Ion Current

https://www.febo.com/pipermail/time-nuts/2017-March/104374.html The -2500 supply is nearly identical to the +3500 supply. We will post some photos on the disassembly process. We also had to disassemble the +3,500 supply because the 200 Meg resistor had gone up in value. It showed only 1,900 V

Re: [time-nuts] Fwd: HP5061B Ion Current

Really good pix on the inside of the 3500V module. So the opening of the can is the typical lots of heat and pry it open approach right? How about a good pix of the 2500 Volt module? Thanks Paul WB8TSL On Sun, Mar 26, 2017 at 6:42 PM, Donald E. Pauly wrote: > https://www.febo.com/pipermail/time-

[time-nuts] Fwd: HP5061B Ion Current

https://www.febo.com/pipermail/time-nuts/2017-March/104374.html We continue to try to achieve lock on our latest HP5061B acquisition. We found that the -2,500 supply would only come up to -780 V under normal 55 Meg multiplier load. When we pulled off the HV lead to the beam tube, it came up to on

[time-nuts] Fwd: HP5061B Ion Current

https://www.febo.com/pipermail/time-nuts/2017-March/104374.html The design on the voltage and current limiter is complete but not breadboarded yet. We are getting a little more time on our HP5061B beam tube after beefing up the +3,500 Volt power supply. We have the frequency control R4 turned al

Re: [time-nuts] Fwd: Fwd: HP5061B Ion Current

dnesday, March 22, 2017 11:32 AM > To: time-nuts; rwa...@aol.com; Donald E. Pauly > Subject: [time-nuts] Fwd: Fwd: HP5061B Ion Current > > https://www.febo.com/pipermail/time-nuts/2017-March/104374.html > > I have posted two HP patents on the cesium beam tube at > http://gon

[time-nuts] Fwd: Fwd: HP5061B Ion Current

: Re: [time-nuts] Fwd: HP5061B Ion Current To: Discussion of precise time and frequency measurement , rwa...@aol.com That's some very nice work, Donald. Looking back, I have junked one or two Cs tubes that might have been usable if I'd thought through the problem of high ion pump current

[time-nuts] Fwd: HP5061B Ion Current

https://www.febo.com/pipermail/time-nuts/2017-March/104374.html You bring up an interesting point. As the cesium is used up over the years, it forms a cesium frost which deposits on everything inside the tube. If it gets thick enough it conducts or can arc between frost grains. A charged capaci

Re: [time-nuts] Fwd: HP5061B Ion Current

That's some very nice work, Donald. Looking back, I have junked one or two Cs tubes that might have been usable if I'd thought through the problem of high ion pump current as you and KB7APQ seem to have done. Another good reason to raise the lockout threshold would be to cut down on the repet

[time-nuts] Fwd: HP5061B Ion Current

https://www.febo.com/pipermail/time-nuts/2017-March/104374.html Paul: I don't think that I made myself clear. This power supply is a rare example of HP engineering incompetence. The transformer is EASILY capable of 10 Watts out at 3500 V. Instead they made it where it can't even put out 100 mW

Re: [time-nuts] Fwd: Dusty 53131A

Hi, To state the obvious, I think the same goes for 53132A and indeed several others. Cheers, Magnus On 03/06/2017 08:19 AM, Bob Camp wrote: Hi 53131’s are dust magnets. It is not at all uncommon for them to fill up with dust, overheat, and die. Popping them open every 10 years or so to cl

Re: [time-nuts] Fwd: Dusty 53131A

Hi 53131’s are dust magnets. It is not at all uncommon for them to fill up with dust, overheat, and die. Popping them open every 10 years or so to clean them out is well worth the effort. Bob > On Mar 5, 2017, at 8:54 PM, Scott Stobbe wrote: > > Recently the fan in my 53131 has been making

[time-nuts] Fwd: Dusty 53131A

Recently the fan in my 53131 has been making a pretty awful sound, so its time to replace it. When I disassembled the counter I found the trim cap had turned into a fur ball. Not that it really matters since it runs on an external reference, but its interesting to see if the dust has any effect. Se

[time-nuts] (fwd) Re: ``direct'' RS-232 vs. RS-232 via USB vs. PPSdecoding cards

> >I think that's enough to synchronize the counter on the Ethernet card with >the CPU counter. You need either something like a PPS connected to both the >Ethernet and some pin on the CPU, or you need some pin the CPU can control >connected over to the Ethernet. It seems like it would be pret

Re: [time-nuts] Fwd: Best replacement for Trimble Bullet antenna

With roof mounted antenna practical issuers are important. 1) Do birds like to tech on it, they will it then can find a way to stand on top of it. They poop on whatever they perch on. 2) Same with snow in some places 3) Can you route the lead wire down the mast? Some antenna mount to a pipe fla

[time-nuts] Fwd: Best replacement for Trimble Bullet antenna

I have a used version of the subject antenna, which is still quite operational. However, I recently needed either a way to tie into reception from this antenna or purchase additional antennas. Given the cost of active patch antennas, I tried one from Adafruit. While comparing reception on a Trimbl

[time-nuts] Fwd: TNS-BUF High Isolation, Low Noise Buffer Amp Available

We've received enough orders to go ahead with production on the TNS-BUF, so here's your last chance to join the cool kids -- we'll take orders at http://tapr.org/kits_tns-buf through tomorrow, Oct. 20. John Forwarded Message Subject: [time-nuts] TNS-BUF High Isolation, Low Noi

[time-nuts] Fwd: CGSIC: Best Practices for Leap Second Event Occurring on 31 December 2016

Fellow time-nuts, I think this might be of some interest. I think the third paragraph is of interest, as it makes clear that owners of equipment have to ensure themselves that it will operate properly with regard to leap-seconds. I think that for the most part, this is a fairly well written

[time-nuts] Fwd: TNS-BUF High Isolation, Low Noise Buffer Amp Available

Just a reminder that the deadline to order TNS-BUF isolation amps is next week -- October 20. John Forwarded Message Subject: [time-nuts] TNS-BUF High Isolation, Low Noise Buffer Amp Available Date: Wed, 5 Oct 2016 10:15:46 -0400 From: John Ackermann N8UR Reply-To: Discussion

Re: [time-nuts] Fwd: "NUT4ANT is a four-channel, all-frequency, GNSS RF-to-bits receiver"

On Thu, 22 Sep 2016 17:29:38 -0700 Bill Woodcock wrote: > > The latest and greatest from Crowd Supply. > > View this email in your browser > > > > > >

[time-nuts] Fwd: "NUT4ANT is a four-channel, all-frequency, GNSS RF-to-bits receiver"

Perhaps of interest, forwarded from CrowdSupply. -Bill > Begin forwarded message: > > From: Crowd Supply > Subject: A satellite-guided floating Panopticon bristling with the talons of > freedom > Date: September 22, 2016 at 2:56:38 PM PDT > To: > Reply-To: Cro

[time-nuts] Fwd: Re: For Sale Reference Synthesizer for Microwave "Brick"

Price reduced, final hours! http://www.ebay.com/itm/162197662488?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649 On 8/22/2016 10:47 PM, Joe Leikhim wrote: For anyone still playing with old school CALIFORNIA MICROWAVE type Microwave brick cavity oscillators. http://www.ebay.com/itm/162

[time-nuts] Fwd: Home-brew GPSDO

-- re-posting with smaller attachment -- On Thu, Mar 17, 2016 at 12:40 PM, Logan Cummings wrote: > I was planning on using the Due's ADC to measure the voltage on the > integrator capacitor, but hadn't decided yet about a "good" current source > vs. a series resistor on the output of an XOR or

Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly

What was interesting was in addition to the bump was that the Garmin nav receiver in the car was unable to get a fix until it did a full cold start Content by Scott Typos by Siri > On Jan 28, 2016, at 5:37 PM, Magnus Danielson > wrote: > > Poul-Henning, > >> On 01/28/2016 11:27 PM, Poul-Henn

Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly

In message <56aa6aa2.6050...@rubidium.dyndns.org>, Magnus Danielson writes: >> And, did this "ripple in the force" cause all those NTP synchronized >> clocks to hiccup (if a NTP ticker is UTC driven vs GPS driven) > >NTP bumping around 13,7 us... I'm not sure I *really* care for most usag

Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly

Poul-Henning, On 01/28/2016 11:27 PM, Poul-Henning Kamp wrote: In message <56aa6aa2.6050...@rubidium.dyndns.org>, Magnus Danielson writes: And, did this "ripple in the force" cause all those NTP synchronized clocks to hiccup (if a NTP ticker is UTC driven vs GPS driven) NTP bumping

Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly

Tom, On 01/28/2016 04:58 PM, Tom Van Baak wrote: I've not been following this discussion too closely, but were the nav solutions from the GPS steady and continuous during the event (that is, was just a time discontinuity). I'm guessing that since the problem was only in the "how to convert from

Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly

Jim, On 01/28/2016 01:22 PM, jimlux wrote: On 1/27/16 11:46 PM, Magnus Danielson wrote: Fellow time-nuts, Here is the official statement. Cheers, Magnus I know we're all time-nuts here and not position-nuts. The thing in the statement that was intriguing was about GPS guided munitions. 1

Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly

> I've not been following this discussion too closely, but were the nav > solutions from the GPS steady and continuous during the event (that is, > was just a time discontinuity). I'm guessing that since the problem was > only in the "how to convert from GPS to UTC" parameters that the nav > s

Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly

On 1/27/16 11:46 PM, Magnus Danielson wrote: Fellow time-nuts, Here is the official statement. Cheers, Magnus I know we're all time-nuts here and not position-nuts. The thing in the statement that was intriguing was about GPS guided munitions. 13.7 microseconds is about 4.5 km. I've not

[time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly

Fellow time-nuts, Here is the official statement. Cheers, Magnus Forwarded Message Subject: CGSIC: FW: Official Press Release - GPS Ground System Anomaly Date: Thu, 28 Jan 2016 01:13:13 + From: Civil Global Positioning System Service Interface Committee (CGSIC) Reply-To

[time-nuts] Fwd: 5065 ?? direct

GREEN LIGHT!!! My last step was to twiddle the two pots (R3 and R11) on the multiplier back and forth a few times (setting them back to their original setting afterwards). 2nd harmonic popped up and is steady. I hit the Logic Reset, and the green light is ON! Error was pretty close to zero, I c

Re: [time-nuts] Fwd: 5065 ?? direct

OK excellent Jim. That should be gud-e-nuf asthey say. On your scope you should be able to sniff the multiplier chain and see if every thing is there certainly at the low end were the sythesiser mixes into the multiplier. I start a business trip in the morning so will not respond till Friday most l

[time-nuts] Fwd: 5065 ?? direct

Paul, I have a 350 MHz scope, HP5335A, various power supplies, DVMs, and sig gens up to 1 GHz. No working Spec An on my bench now, but I have access to one if needed... Jim -- Forwarded message -- From: paul swed Date: Tue, Dec 8, 2015 at 1:35 PM Subject: Re: 5065 ?? direct T

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