Re: [time-nuts] Cesium Clock Avialable

Hi Doug. Did not see my email go by. Would like to have the cs standard. I'm visiting my family in Huntington Beach and can pick it up so no packing. Have cash. Off list at djl at Montana dot com Thanks Don AJ7LL On 2018-05-18 22:04, Doug Millar via time-nuts wrote: Hi, I am willing to part

Re: [time-nuts] Cesium Clock Avialable

Hi Doug I'm visiting just down the coast and could pick up the HP. If not sold I'll take it. Don AJ7LL On 2018-05-18 22:04, Doug Millar via time-nuts wrote: 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

Re: [time-nuts] Better quartz crystals with single isotope ?

Darn. maybe not grain boundaries, but dislocations? or both? Don On 2018-04-22 10:19, Poul-Henning Kamp wrote: Silicon comes in a number of isotopes but 95% of it is Silicon-28. When you make pure mono-crystaline silicon, you get 50-60% better thermal conductivity if you only use Silicon-28

Re: [time-nuts] Better quartz crystals with single isotope ?

Interesting indeed! Seems as if there ought to be info about drawing crystals mono vs poly isotopic somewhere out there. Also some info about crystal grain boundaries that might be generated in a zone furnace drawing by isotope inclusions. Seems the boundaries are responsible for the sudden

Re: [time-nuts] Pulsars, clocks, and time nuts (Jim Palfreyman)

Nice, Jim!!! On 2018-04-13 01:54, Tom Van Baak wrote: Amazing news... 1.2.3. 1) Many of you know that pulsars are weird astronomical sources of periodic signals. Some are so accurate that they rival atomic clocks for stability! True, but I don't have a 100 foot antenna at home so I'll take

Re: [time-nuts] quartz / liquid nitrogen

Tom: I sense a nice experiment! Dry ice temps can be attained with modest Dewars and thermoelectric fridge devices. PID controller and bob's your uncle. Type K thermocouple modules on epay. With that apparat, a nice set of adev vs temperature possible? Dry ice/acetone or ethyl alcohol

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

] http://hackaday.com/2018/03/02/new-part-day-atmegas-with-programmable-logic/#respond [15] http://hackaday.com/2018/03/02/new-part-day-atmegas-with-programmable-logic/#comments [16] https://subscribe.wordpress.com/?key=d109931f8119f9f47c8f2ccdf1639bbfemail=djl%40montana.comb=Cu-jouj-AjzbRThX%5DBc

Re: [time-nuts] Time nut over from the old days

Pete: I need a handwarmer. We're having a colder than usual winter. Don On 2018-02-28 12:45, Pete Lancashire wrote: If anyone wants it, he or she that comes up with the coolest reason can have it. It rattles so I will take a look inside and post what I find -pete On Feb 28, 2018 10:54 AM,

Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

Fine. The Chinese have no concept of, or ignore, intellectual property rights. They will cheerfully use 13 year old girls to put together stuff using counterfeit parts and ripped circuits. There is little or no quality control. The problem is that these goods drive better goods out of the

Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

Chinese made, ... This part looks almost identical to the Trimble Microcentered antenna I worked on recently. Right. It's Chinese made. 'nuff said. Don ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] Looking for some Frequency Electronics info....

start with the power supplies, and go on until morning... Don On 2018-02-19 16:57, walter shawlee 2 wrote: I recently got a strange little 1U FEI rack mounted unit called an FE-7923F-100-1, which appears to have rear 10MHz and dual 100Mhz outputs. it is called a Frequency Reference Unit.

Re: [time-nuts] Anyone have experience with this antenna?

There's a picture of the guts in the ebay description...it's a dual patch antenna! the patches seem to be trimmed to get a pattern. On 2018-02-05 20:33, John Green wrote:

Re: [time-nuts] PBS, Tue evening, The Secret of Tuxedo Park

pbs video player sucks big ones... On 2018-01-16 18:47, Joseph Gray wrote: If you want to watch this episode online, go here: http://video.unctv.org/video/3008204310 This is the UNC Public TV web site. Joe Gray W5JG On Tue, Jan 16, 2018 at 2:28 PM, Bill Tracey wrote: To

Re: [time-nuts] Allan variance by sine-wave fitting

True that the models depend on the noise statistics to be iid, that is ergodic. That's the first assumption, and, while making the math tractable, is the worst assumption. Don On 2017-11-28 01:52, Mattia Rizzi wrote: Hi This is true. But then the Fourier transformation integrates time from

Re: [time-nuts] Allan variance by sine-wave fitting

Forgot to add I think this can be proved mathematically. It's been a long time Don On 2017-11-22 12:52, djl wrote: You have it right, Bob. fitting is essentially a narrow band filter process. Fitting thus has essentially the same errors. Don On 2017-11-22 09:19, Bob kb8tq wrote: Hi

Re: [time-nuts] Allan variance by sine-wave fitting

You have it right, Bob. fitting is essentially a narrow band filter process. Fitting thus has essentially the same errors. Don On 2017-11-22 09:19, Bob kb8tq wrote: Hi The “risk” with any fitting process is that it can act as a filter. Fitting a single sine wave “edge” to find a zero is not

Re: [time-nuts] chrony vs ntpd

Would a step recovery diode be better? for example http://www.mwrf.com/analog-semiconductors/designing-step-recovery-diode-based-comb-generator Don On 2017-10-28 12:20, jimlux wrote: On 10/28/17 10:34 AM, John Ackermann N8UR wrote: Jim, I thought about using an RF-input sync pulse for

Re: [time-nuts] Machining some aluminum help!

Good even for mild steel too. Best is your good advice to use the drill press to keep the tap aligned. softer aluminum alloys are very "sticky" and demand backing off a turn for almost every turn forward for cutting taps to break the chip. I've found that the 6/32 tap is the most easily

Re: [time-nuts] 5370B Input Board Repair [WAS: 5370B Question / help needed]

Could it be that someone thought adhesive would be less prone to cracking from stress than solder? Also, do you think that the adhesive could be cleaned one end at a time and replaced with solder? I'm admittedly too lazy to look/try just now. Don On 2017-07-19 07:09, Gary Neilson wrote: This

Re: [time-nuts] Yet Another GPSDO design - Timing on the move

Thanks! for the nice reply. I did as you suggested and got a copy! Don On 2017-06-26 15:43, Jan-Derk Bakker wrote: On Mon, Jun 26, 2017 at 10:43 PM, djl <d...@montana.com> wrote: I'd really like to have a look at the schematic, but trying to read it leads to some app requiring me to b

Re: [time-nuts] Yet Another GPSDO design - Timing on the move

d'oh never mind don On 2017-06-26 14:43, djl wrote: I'd really like to have a look at the schematic, but trying to read it leads to some app requiring me to bare my machine's soul to an unknown app developer. Could plain .pdf be put somewhere not involving Google? Thanks don On 2017-06-26 14

Re: [time-nuts] Yet Another GPSDO design - Timing on the move

I'd really like to have a look at the schematic, but trying to read it leads to some app requiring me to bare my machine's soul to an unknown app developer. Could plain .pdf be put somewhere not involving Google? Thanks don On 2017-06-26 14:17, William H. Fite wrote: On Monday, June 26,

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] The Witching Hour; short fiction that will likely amuse time-nuts

But what if Tal Avda is in Arizona On 2017-05-21 14:50, Gregory Maxwell wrote: Found on the web: http://slatestarcodex.com/2013/11/03/the-witching-hour/ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] A good GPS-Receiver with 1PPS output...

Can't find this on Tindie??? On 2017-05-10 09:03, Mark Sims wrote: The GPS with the lowest PPS jitter/sawtooth is the Venus timing receiver... around 6 ns. Nick Sayer sells one on Tindie for $50. It is mounted on a board that has the same pinouts as the Adafruit Ultimate GPS. Also Navspark

[time-nuts] odd frequencies

Hi: Ran across this recently, for those looking for odd stable frequencies. http://www.qrp-labs.com/ocxokit I haven't built one of these, but for $16 plus shipping, hey. It does use a single-loop oven, built in. I've had conversation with QRP labs, and found them knowledgeable and congenial.

Re: [time-nuts] Vintage Frequency Measurement

The BC-221 was the backbone of WW2 communications. How else were all those sloppy BC-348's and AR-13's set to the called-for frequencies? Same for shipboard. Don On 2017-02-13 13:05, Brooke Clarke wrote: Hi Bob: The BC-221 is usually referred to as either a Frequency Meter or a Heterodyne

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

bought any prescription drugs lately? On 2017-01-20 09:58, Bob Camp wrote: Hi I completely agree that their spin at acquisition and the reality of what just came out is completely amazing. They said they would never do this and that. What they are doing is exactly what they said they would not

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

Interesting, Tom. I don't think I see any of those pesky grain boundary shifts or readjustments in the lattice structure? If I remember, these can cause instant shifts in frequency that do not heal? Don On 2016-11-12 14:54, Tom Van Baak wrote: There were postings recently about OCXO ageing,

Re: [time-nuts] HP 5275A

Just homemade opto-isolators. Used in choppers, too. The transistor was indeed bonded to the heatsink. Just replace the whole thing with a 3-legged regulator? or simply a modern PNP t0-220 with a little heat sink on it. 73, Don On 2016-11-06 15:15, paul swed wrote: Don't know what to say on

Re: [time-nuts] So what’s inside that Cs Beam Tube anyway?

Echo, Magnus. Thanks, Skip! Easy now to see the incredible expense of building one of these! Kinda Kludgy; Love the s/s spot welded keepers on the screw heads, e.g. My really dumb question is, why isn't there Cs plated on everything? Or is the Cs contained in the rf cavity only? I think I see

Re: [time-nuts] New PPB rated TCXO

But how the heck did they get some? According to the website, even data sheets are not available. Don On 2016-10-10 21:32, Henry Hallam wrote: I can attest that that oscillator was a lifesaver recently in a project I was tangentially involved with. They had tried several TCXOs and were

Re: [time-nuts] New PPB rated TCXO

Looks promising, but with no data sheets and no purchase source or pricing, just more vaporware... Don On 2016-10-10 20:02, Nick Sayer via time-nuts wrote: The video linked on that page is particularly interesting (if you take it on face value that they're not faking it. ;) ). Sent from my

Re: [time-nuts] HP 59309A Clock runs, sets via GPIB, but no GPIB output?

Hi Bob et al: I have 4 of these, got some time ago. Here is the data from the ROM's: s/nRom no 2510A04059 hp1818-2295A 2335 2136A03167 hp1818-2295A 0844 this one white ceramic with lotsa gold; the eldest. 2702A04579$M$hp1818-2295A 2912 this one costcutting.

Re: [time-nuts] TimeLab

That's easy, Magnus. Do not use a Fluke counter :-) Don On 2016-10-09 13:02, KA2WEU--- via time-nuts wrote: You guys never give up, happy Sunday In a message dated 10/9/2016 2:46:02 P.M. Eastern Daylight Time, mag...@rubidium.se writes: Hi, Agree. However, one need to make sure that the

[time-nuts] cleanup

of good road off I90. Contact me off list at djl ampersand montana dot com. There is more stuff here as well. Big sale. Thanks for your patience. Don -- Dr. Don Latham PO Box 404, Frenchtown, MT, 59834 VOX: 406-626-4304 ___ time-nuts mailing list -- time

Re: [time-nuts] Quartz Crystal Motional Movement

excellent vid, Bryan! On 2016-06-25 03:48, Bryan _ wrote: Quartz Crystal motional movement... https://youtu.be/y-rCgumTn4Q -=Bryan=- ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] Commercial software defined radio for clock metrology

This might be a good job for the Red Pitaya q.v. Don On 2016-05-27 18:17, Bruce Griffiths wrote: On Thursday, May 26, 2016 06:40:26 PM Bob Camp wrote: Hi Very interesting paper, thanks for sharing !! One question: In many DMTD (and single mixer) systems, a lowpass and high pass filter are

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

I like the little boards at: http://navspark.mybigcommerce.com/development-boards/ It's a GPS with a fully programmable 32-bit Arduino-compatible processor. $22 Crowdsourced about 3 yr ago, matured now. Various versions; you can even have Beidou :-). Don On 2016-05-22 19:45, Tom Van Baak

Re: [time-nuts] Precise Time transfer and relative position over a short baseline

I have not followed this closely. Why not use the data itself? The theoretical pattern for the telescope pair can be calculated. Even though the signals are not i.i.d, from phototubes, the data can be slid along and the delay pattern established and compared to the theoretical pattern? Timing

Re: [time-nuts] FEI-5660 Rubidium Oscillator

granite is not only radioactive, but also piezoelectric. Dpn On 03/29/2014 12:48 PM, Magnus Danielson wrote: On 28/03/14 04:47, Mark Sims wrote: no, No, NO granite! Granite tends to be rather radioactive (particularly avoid the pink stuff). Any audiofool worth his tin ears can't have no

Re: [time-nuts] GPSDO simulation tool

Well done! Don On 03/21/2014 03:55 PM, Tom Van Baak wrote: Designing a GPSDO is a permanent topic of time-nuts, and always invites lots of opinions and methods. The net performance of a microcontroller-based GPSDO is mostly due to the following ingredients: - the stability of the OCXO (or