Re: [time-nuts] Two pieces of old General Radio Freq. Nuts

HP used GR connectors in the 1415A Time Domain Reflectometer plug-in for the 140-family of oscilloscopes. I believe this is the only use of the GR connector in HP's "common" test instruments. Jeremy On Fri, May 26, 2017 at 10:13 PM Bill Byrom wrote: > Yes, the GR-874 was

Re: [time-nuts] Two pieces of old General Radio Freq. Nuts

Hi > On May 26, 2017, at 11:21 PM, Gary Woods wrote: > > On Mon, 22 May 2017 05:59:59 -0700, you wrote: > >> https://goo.gl/photos/tygN5ZFeFLUhc4zX6 >> >> Near Portland Oregon > > Neat stuff...did anybody but GR use those hermaphrodite connectors? At one time, GR

Re: [time-nuts] Two pieces of old General Radio Freq. Nuts

Hi Gary, I have seen them on old HP, Tektronix, and a few other brands. GR was the most famous for them tbough that I've seen. Mark KC0OHJ On May 26, 2017 9:52 PM, "Gary Woods" wrote: On Mon, 22 May 2017 05:59:59 -0700, you wrote:

[time-nuts] More TruePosition Arduino

Good morning all, First, a big thank you to Chris and a couple of other people who pointed me towards the low-cost USB logic analyzers. After some hair-pulling, I got it working with PulseView and it works fantastic! This morning, I spent some time adding various lines to my Arduino code

[time-nuts] Mystery Oscillator

Found an old oscillator when cleaning out a barn. It is a model YH890-1 made by Greenray Industries. Since it is 10 mhz. output, I though it might be useful for something. It has a BNC connector which I assume is the output and three terminals on the side. One is chassis ground. The label says

Re: [time-nuts] Two pieces of old General Radio Freq. Nuts

Yep, GR once made the best. The GR connector had at least three things going; as noted hermaphroditic. No need for several sexes. Second, they are seamless 50 ohms, very very small reflections at the connection. Third, banana plugs (also a GR idea, I think) fit in the center "post" of the

Re: [time-nuts] GPS Kit Plates

Jerry - Yes, from the GPS DE-9M connector to the PC (RS-232) and the DC power source. I have been DIY building D-subminiature cables since 1980 (parts not an issue). The SynPaQ/E version XTS (DE-9M) pin assignments are "non-standard" (not RS-232) and include DC power input, as well as 1 PPS

[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

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

I agree with some of what Donald and Rick are saying. But does anyone actually use a locked Cs standard for its short-term stability (e.g., tau < 10 s)? If that's your goal then what you do is run the standard in Cs-Off (free-run, standby) mode. Or just use best old OCXO you can find and

Re: [time-nuts] GNSS Disciplined Clock

Hi Second to second jitter *could* be another interpretation of the 15 ns. That would be a pretty loose number. Modern stuff after sawtooth correction gets down to < 1 ns on that basis. Since it’s a GPSDO, I would guess it’s under 1 ns (1x10^-9) at one second. Correcting for timing bias to

Re: [time-nuts] GNSS Disciplined Clock

Dear Chris As far as I know, atmospheric effect can not be compensated by looking at satellites from all over the sky and averaging, since it does not have a random nature, rather it introduces bias to the solution. For example, if atmospheric effect is not removed, one can not get a relative

Re: [time-nuts] GNSS Disciplined Clock

Dear Bob As I understand from your response, 15 ns reflects the jitter, i.e. the time difference between successive PPSs is not exactly 1 second and its standard deviation (one sigma) is 15 ns. In that case, "precision" is more appropriate than "accuracy" to be used in the datasheet. Moreover,

Re: [time-nuts] GPS Kit Plates

Jerry, Greg is referring to the adapter cable to split the power and pps out of the DB9. There may be enough interest to do a small second round. The prices would be higher due to the lower quantity. I'll give it some thought while I'm on my short overseas assignment June 4-11. Happy

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

Hi Having run a 5071A with a *very* good 10811 in it, the OCXO does dictate what happens at 0.1 seconds. Once you get past that, you are headed into a bit of a gray zone. You are partly looking at the Cs and partly looking at the OCXO. Pushing out the crossover between the two could help you

[time-nuts] HP5061B Versus HP5071 Cesium Line Frequencies

Donald, Will look forward to seeing your Allan Deviation plots before and after. That will be the only way to verify your modification will make any improvement. I suspect the improvement at a few seconds will degrade it at other Tau. Cheers, Corby

Re: [time-nuts] GPS Kit Plates

Steve and Jerry - Thank you for coordinating the acquisition and machining of these End Panels for the TAPR GPS Experimenters Kit. I understand these kits (SynPaQ/E version XTS) are EXHAUSTED at TAPR. Check the TAPR web site for details. https://www.tapr.org/gps_exp-kit.html The End Panels

Re: [time-nuts] GPS Kit Plates

Greg, to which adapter cable are you referring? From the PC to the DB9? What I did in the meantime was use breadboarding jumpers. The square female ends typically will press onto the DB9 male pins. Glad they fit your need. Steve, sounds like there won’t be another round? Jerry > On May

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