Re: [time-nuts] (UK) NPL open house

. No absolute confirmations yet, as one of the people I wanted to visit is going on jury service tomorrow, but I'm hopeful one of his colleagues can show me around. Dr David Kirkby Ph.D C.Eng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, CHELMSFORD, Essex

Re: [time-nuts] Dual GPSDO - any advantage?

On 10 April 2018 at 16:56, donald collie wrote: > I have the Chinapost tracking numbers, so I don`t think it`s a scam - just > real good value. I hope you are right, but I doubt you are. It is not uncommon to be sent fake tracking numbers. I was 99% sure a Keithley

Re: [time-nuts] Dual GPSDO - any advantage?

On 10 April 2018 at 17:11, Clint Jay wrote: > Sad to say I think I was right, the listings have been pulled already and > the seller now has zero items for sale. > The listing has not been pulled. Yes the seller has 0 to sell, but because he has sold out of the 100. I still

Re: [time-nuts] Dual GPSDO - any advantage?

On 10 April 2018 at 16:23, Dr. David Kirkby <drkir...@kirkbymicrowave.co.uk> wrote: > On 10 April 2018 at 15:32, Clint Jay <cjaysh...@gmail.com> wrote: > >> Ahh, I've found the listing, has anyone received one? >> >> I hate to say this but I'm highly s

Re: [time-nuts] Dual GPSDO - any advantage?

On 10 April 2018 at 15:32, Clint Jay wrote: > Ahh, I've found the listing, has anyone received one? > > I hate to say this but I'm highly sceptical that they will ever turn up, > looks and smells very much like the standard eBay scam to me. > -- > Clint. M0UAW IO83 > I'm

Re: [time-nuts] Weird Stuff WareHouse shutting down

On 8 Apr 2018 16:56, "jimlux" wrote: > > Test equipment tends to be aged - Unless you have a particular need for a HP 600 series microwave signal generator, there are probably better sources available much cheaper that use more modern components. In this day and age, I

Re: [time-nuts] Environmental sensor recommendations.

On 5 April 2018 at 15:44, John Green wrote: > Why has no one mentioned thermocouples? > I had some experience with thermistors a few years back designing thermal > attenuators and equalizers for CATV. NTC thermistors can have a large > change of resistance for a unit change in

[time-nuts] Open day at the National Physical Laboratory (NPL) on Thursday 17 May 2018.

NPL opens their doors to the public once every 2 years. It is well worth going. Tickets are only 3.00 each, and that money is donated to a cancer charity. More details at http://www.npl.co.uk/open-house/ To make the most of it, you need to 1) Arrive early (14:00) 2) Leave when they close

Re: [time-nuts] WWV/CHU

On 30 March 2018 at 06:49, Tom Van Baak wrote: > > FYI: for the original spam-free version, please use: > > https://tf.nist.gov/general/pdf/469.pdf > > In general, if the author or paper is related to NIST, the original > copyright-free PDF will be available in the NIST Time

Re: [time-nuts] Need a Watch Recommendation

On 5 March 2018 at 16:50, William H. Fite wrote: > And that is just my point--well, part of it, anyway--ultra-precise > measurement of time is profoundly important, and rightly the primary focus > of this group. But for the wrist, very, very few of us need pin-point >

Re: [time-nuts] eBay GPS antenna test results.

On 9 February 2018 at 21:43, John Green wrote: > To those who doubted that the antenna was actually a 3.3 to 18 volt design, > it seems you were correct. Today, I hooked it up to a variable power supply > and slowly raised the DC voltage fed to the antenna. It began to pull >

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

pay the return cost. Dr David Kirkby Ph.D C.Eng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Chelmsford, Essex, CM3 6DT, United Kingdom Registered in England and Wales as company number 08914892 http://www.kirkbymicrowave.co.uk/ Tel 01621'680100 / +44 16

Re: [time-nuts] Stable32 now available

On 5 January 2018 at 14:21, Graham wrote: > Lulu is currently having a promotion with free postage for those > contemplating ordering a copy of the manual from Lulu. > > Get free mail or 50% off ground shipping! > Use promo code *SHIPIT2018* > Expires Jan 8 at 11:59 pm ET >

Re: [time-nuts] Stable32 now available

On 3 January 2018 at 11:08, Poul-Henning Kamp wrote: > > Anyway, code like this can be written to compile and work across all the > relevant *IX operating systems with a minimum of effort, so I don't think > a separate port to any of *BSD, Linux, Solaris or AIX should be

Re: [time-nuts] Stable32 now available

On 3 January 2018 at 04:09, Tom Van Baak wrote: > I asked Bill for clarification and here's some of what he shared: > > > Tom: > > > > I’m glad that the word is getting out that Stable32 is now freely > available. > > > > My donation to the IEEE UFFC included all source

Re: [time-nuts] Stable32 now available

On 2 January 2018 at 14:10, paul swed wrote: > Jelen > Thank you for informing us about Stable32. I have been busy downloading > details. > I was surprised by the size of the use manual at some 348 pages. > I believe I have a very long way to. I suspect we need a Stable32

Re: [time-nuts] Stable32 now available

On 2 January 2018 at 09:30, Matthias Jelen wrote: > Dear Time-Nuts, > > Happy New Year! > > Maybe this is of interest for some of you: > > A copy of Stable32 was on my wish-list for Christmas and I asked for the > possibility of a non-profit-license. Bill Riley informed me

[time-nuts] Cheap ($90) time interval counter on eBay

I can't possibly imagine that this is going to have the performance of the high end TI counters, but it might interest someone to have a play without breaking the bank. https://m.ebay.com/itm/ADC-100A-Time-Interval-Analyzer-Tested-Working-/261303897956 Dave

Re: [time-nuts] External cooling fans - source

On 18 December 2017 at 23:11, Charles Steinmetz wrote: > From time to time, the subject of external cooling fans comes up -- for > example, in discussions of the HP 5370A/B with their steaming hot > heatsinks. I have several times recommended very quiet, all-metal, 4"

[time-nuts] "Timekeeping today – from stars to atoms" lecture by Peter Whibberley of NPL, organised by IET.

This might interest some. It's on 6th December in London.

Re: [time-nuts] Favorite counters (current production)?

On 10 November 2017 at 16:37, Bob Camp wrote: > Hi > > There is no perfect answer. I’d go with the 53230 simply because it > *might* be supported > the longest. > > Bob > If I had to take a bet, I would say the SR620 will be supported longer. Stanford Research seem to be selling

Re: [time-nuts] R XSRM Rubidium Standard

On 15 Sep 2017 10:45, "Scott McGrath" wrote: > > Precisely my point, But when purchasing i expect to pay for a calibration at a minimum. I have on occasions requested sellers to send an item to the manufacturer (Agilent or Keysight) for calibration *before* shipping it to

Re: [time-nuts] Something for all TIME NUTS!!

On 27 June 2017 at 23:02, Don Murray via time-nuts wrote: > Hello all... > > For the SERIOUS time nut... you might want to give yourself a few hours > before you go check out this site... and beyond!! > > 73 > Don > W4WJ > > >

Re: [time-nuts] SR620 TCXO calibration

On 19 June 2017 at 21:43, David C. Partridge wrote: > Yes please. ... > OK, the code is here http://www.kirkbymicrowave.co.uk/tmp/srs-0.02.tar.gz Note 1) It has only be tested on Solaris SPARC, with a National Instruments GPIB card. 2) I would expect it to run

Re: [time-nuts] SR620 TCXO calibration

I should have added, mine had an OCXO - I just see you had a TCXO. I don't have the SR620 any more. I swapped it, along with a HP 4.2 GHz signal generator, for an HP 4291B impedance and material analyzer. Dave ___ time-nuts mailing list --

Re: [time-nuts] SR620 TCXO calibration

On 19 June 2017 at 15:35, David C. Partridge wrote: > I think I'm being dense, but I can't work out how to get this thing to > display CalDat 04. I have managed to get it to display CalDat 0 value, > but > can't work out how to step through to view adjust CalDat

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

On 5 June 2017 at 00:59, Attila Kinali wrote: > Moin, > > This discussion is kind of getting heated. > Let's put some facts in, to steer it away from > opinion based discussion. > I can't find it now, but I know someone said thermocouples are obsolete. I spoke to a friend

Re: [time-nuts] Measuring coax temperature coefficient with a TICC

Pi f C >> G, so it simplifies to sqrt(L/C). Those two assumptions become less valid at low frequencies. Overall, what you are doing seems interesting, but I would question how much the results will relate to real-world use of coax, where its not normal to have great real of it. Dr. David

Re: [time-nuts] Vintage Frequency Measurement

On 12 February 2017 at 06:08, Scott Stobbe wrote: > I was inspired recently coming across a Lampkin 105 frequency meter, as to > how frequency measurement was done before counters. > > Certainly zero-beating a dial calibrated oscillator, would be one approach. > > Is

Re: [time-nuts] Line Frequency standard change - Possible ?

On 9 February 2017 at 21:31, Poul-Henning Kamp wrote: > > The only other possible "balance signal" is the voltage, and it > suffers from a host of noise mechanisms, from bad contacts and > lightning strikes to temperature, but worst of all, it takes double > hit when you

[time-nuts] HP 58503A GPS time and frequency receiver - How do I determine why the ALARM LED is on?

I've got an HP 58503A purchased from China a couple of years ago. It has a bit of a hard life, having been in water at some time. But it seems to work ok, as far as I can tell. Today there was a power failure for 5 minutes or so. The red ALARM LED is on. It is not clear to me why, although of

Re: [time-nuts] Thermal effects on cables

On 23 January 2017 at 17:29, Tim Shoppa wrote: > > Funny how people always want to put the words "dielectric" and "constant" > right next to each other but we know it isn't constant :-) > > Tim N3QE > Yes. I will have to look into this, as I see some quite widely different

Re: [time-nuts] Thermal effects on cables

oI On 23 Jan 2017 17:02, "REEVES Paul" wrote: > > Hi David, Hi Paul > Surely the impedance of the cable is only affected by the ratio of the inner conductor and outer conductor diameters modified by the internal dielectric constant, nothing to do with the

Re: [time-nuts] Thermal effects on cables

On 13 January 2017 at 06:52, Ole Petter Ronningen wrote: > Hi, all > > The question of phase shifts in cables pops up every now and then on this > list - I stumbled across a good table of measured phase shifts with > temperature in different cable types in this paper: >

Re: [time-nuts] HP 55300A Date Problem

On 21 January 2017 at 17:29, Gary Neilson wrote: > I have a HP 55300A Telecom Primary Reference Standard that I am using as a > frequency reference (10 mhz) in my lab. > I suppose this is one of those open-ended questions, but what the definition of a "Primary Reference"?

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

On 12 January 2017 at 02:31, Bob Camp wrote: > Hi > Hi Bob > > The most basic issue you are going to run into is that your counter is not > high enough > resolution / accuracy to give you meaningful data for time intervals under > a few hundred > seconds. Is that true if I'm

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

MY AIMS 1) Try to learn about the various statistical tests (ADEV, MDEV etc), and how best to compare oscillators, by making some measurements on various oscillators I have. 2) Investigate the short/medium term stability of the output of various bits of test kit. All are locked to GPS by

Re: [time-nuts] hm H Maser

On 10 January 2017 at 15:35, Ole Petter Rønningen wrote: > ... having said that, I for one think I'm with Bob on this one. The thing > about masers are that they are big. At least active masers. And they > require a substantial volume be kept at ultra high vacuum - which

Re: [time-nuts] hm H Maser

Once 9 Jan 2017 12:59, "Bob Camp" <kb...@n1k.org> wrote: > > Hi > > Ok here are some rough numbers: > > > On Jan 9, 2017, at 4:35 AM, Dr. David Kirkby (Kirkby Microwave Ltd) < drkir...@kirkbymicrowave.co.uk> wrote: > > It would be interesting

Re: [time-nuts] What signals if any are on the unpopulated SMC pads onthe 58503A motherboard?

On 9 January 2017 at 10:44, Roy Phillips wrote: > I would be grateful for an answer to this question, as I also have a an HP > 58503 - is the manual for the instrument available for download ? > Thank you > Roy > I know its a bit unlikely to use SMC in such a case, but

Re: [time-nuts] hm H Maser

On 8 Jan 2017 17:34, "Bob Camp" wrote: > You are talking about a project that will take many years and likely > more money than the price of a new home. If that is “fun money”, then > fine. For most people that sort of commitment is a bit outside the range > of do it for fun. It

Re: [time-nuts] hm H Maser

On 8 January 2017 at 15:22, Bob Camp wrote: > Hi > > I guess the question then would be: > > Is a H Maser that runs 6.6 x 10^-12 at 1 second worth the trouble? > > With 100 KHz / C temperature coefficients running around, getting > good stability in a real world setting at 1 day

Re: [time-nuts] Line Voltage - USA

On 4 January 2017 at 14:25, Dr. David Kirkby (Kirkby Microwave Ltd) < drkir...@kirkbymicrowave.co.uk> wrote: > > I just phoned Tektronix and they want £160 (GBP) + VAT to calibrate this > 6000 count handheld DMM. Ouch. I will not bother with that. > Sorry, 60,000 to

Re: [time-nuts] Line Voltage - USA

Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, company number 08914892. http://www.kirkbymicrowave.co.uk/ Tel: 07910 441670 / +44 7910 441670 (0900 to 2100 GMT only please) On 4

Re: [time-nuts] Line Voltage - USA

On 4 January 2017 at 09:34, Poul-Henning Kamp wrote: > > > >Do you have a reference to this +6%? I've heard from various sources that > >the UK is 230 -6%/+10%. If the EU dictates otherwise, then I'm certainly > >over the 6% limit. I may or may not be over the 10%

Re: [time-nuts] Line Voltage - USA

On 2 January 2017 at 05:15, Jeremy Nichols wrote: > Thank you for the detailed analysis, Bill. The voltage measurements I made > in my garage laboratory were duplicated by the utility with their meter, > which was connected at the service entrance. I have just been chatting

Re: [time-nuts] Line Voltage - USA

On 2 January 2017 at 18:14, Poul-Henning Kamp wrote: > > In message qnosgqvz...@mail.gmail.com> > , Tim Shoppa writes: > > >What modern loads are actually sensitive to high (say, +10 to +20%) line > >voltage? > > In EU you're supposed to have 230V +/- 6% in your

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

On 30 December 2016 at 23:58, Dr. David Kirkby - Kirkby Microwave Ltd < drkir...@kirkbymicrowave.co.uk> wrote: > I bought a 5370B TI counter which arrived today. It needs a bit of TLC, > but nothing too bad. But one of the rotary knobs is incomplete. Does anyone > have a spare k

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

On 2 January 2017 at 18:21, Robert Atkinson wrote: > I've a spare knob and it's on it's way to Dave. f > Cheers Robert. I'll send you some money. Drop me a private email with your PayPal address. > 5370 counters do seem to run hot so I don't think you have a fault. As

[time-nuts] Reproducibility of position data from multiple surveys of HP 58503A GPS receiver

ut I stand to be corrected. -- Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, company number 08914892. http://www.kirkbymicrowave.co.uk/ Tel: 07910 441670 / +44 7910 441670 (0900 to 210

Re: [time-nuts] Line Voltage [Was: Anyone (ideally in the UK) ...]

On 1 Jan 2017 11:10, "Hal Murray" wrote: > > The nice thing about the APC units is that they are close to free if you are > already going to purchase a UPS. > > I agree that something like the Dranetz 658 would be better, but a quick peek > at eBay shows prices far beyond

Re: [time-nuts] Line Voltage [Was: Anyone (ideally in the UK) ...]

On 1 Jan 2017 05:07, "Chris Albertson" wrote: > > Just a comment for anyone who wants to log line voltage v. time. If > you have an APC "Smart UPS" battery backup unit these will log voltage > and frequency to a file. If the information is for your own use only, that

Re: [time-nuts] Capture of leapsecond on HP 58503A time and frequency reference receiver

Reposting the output in a fixed width font. It looked fixed on my other client. I note the clock says "Time _ +1 leap second pending" at 23:59:60, which one can argue is wrong. *Status reports a couple of times before the leap second. * scpi > SYSTEM:STATUS? ---

Re: [time-nuts] Leap-second capture on laptop

On 1 January 2017 at 01:00, Magnus Danielson wrote: > Fellow time-nuts, > > While not fancy by any means, my laptop captured the leap-second being > inserted by this message in the /var/log/syslog: > Jan 1 00:59:59 greytop kernel: [78458.839942] Clock: inserting leap

[time-nuts] Capture of leapsecond on HP 58503A time and frequency reference receiver

LON E 0:46:36.343 ELEV MASK 10 deg HGT +44.72 m (MSL) HEALTH MONITOR . [ OK ] Self Test: OKInt Pwr: OK Oven Pwr: OK OCXO: OK EFC: OK GPS Rcv: OK scpi > -- Dr. David Kir

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

On 31 December 2016 at 13:03, EB4APL wrote: > Hi, > > I'm not totally sure about the limits, but I have read several times that > in the UK the nominal supply voltage is 230 V +10%/−6% to accommodate the > fact that most supplies are in fact still 240 V. The context was that a

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

On 31 Dec 2016 02:03, "Bob Stewart" wrote: > > 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

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

of the 11 kV transformer, so other properties around me probably get poorer voltage regulation, but a few less volts. Dave -- Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, company

Re: [time-nuts] Problem with HP 83623A 20 GHz sweep generator stepping up/down 100 Hz when not wanted.

On 22 December 2016 at 20:54, Bill Byrom wrote: > Read about the synthesizer design of that generator here: > > https://ia600407.us.archive.org/10/items/Hewlett-Packard_ > Journal_Vol._42_No._2_1991-04_Hewlett-Packard/Hewlett- >

Re: [time-nuts] Problem with HP 83623A 20 GHz sweep generator stepping up/down 100 Hz when not wanted.

On 22 December 2016 at 01:35, Brooke Clarke wrote: > Hi David: > > Do you have a comb generator? > No. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] Problem with HP 83623A 20 GHz sweep generator stepping up/down 100 Hz when not wanted.

On 22 December 2016 at 03:51, Tom Knox wrote: > If it is any help, the 836XXA/B series are all capable of 1Hz resolution > but are locked at 1KHz unless you enter the license key for option 008. So > it could be software/firmware related. > > Happy Merry; > > Thomas Knox > I

Re: [time-nuts] Problem with HP 83623A 20 GHz sweep generator stepping up/down 100 Hz when not wanted.

On 22 December 2016 at 03:17, paul swed wrote: > Dave Congratulations on 10 Ghz SSB. > This was not a QSO at all. It was simply a one way transmission from a signal generator at my end to a receiver at his end. No QSO was attempted. > Now to your question. I will fully

[time-nuts] Problem with HP 83623A 20 GHz sweep generator stepping up/down 100 Hz when not wanted.

I run a test over the weekend with a fellow radio ham. I transmitted 100 mW or so at 10368.115 MHz from an HP 83623A 10 MHz to 20 GHz sweep generator http://www.keysight.com/en/pd-101862%3Aepsg%3Apro-pn-83623A/synthesized-sweeper-10-mhz-to-20-ghz-high-power?cc=GB=eng into a small horn

Re: [time-nuts] Problem with HP 83623A 20 GHz sweep generator stepping up/down 100 Hz when not wanted.

On 21 December 2016 at 23:42, Dr. David Kirkby (Kirkby Microwave Ltd) < drkir...@kirkbymicrowave.co.uk> wrote: > But one thing to possibly is > > * Set sweep generator to 10.368 GHz > * Set sweep generator to 10.378 GHz, so there's a 10 MHz difference. > I mean set the V

Re: [time-nuts] Why is holdover LED on HP 58503A not lit, when GPS lock is unlit too?

On 18 December 2016 at 22:41, Dr. David Kirkby (Kirkby Microwave Ltd) < drkir...@kirkbymicrowave.co.uk> wrote: > It is looking much better now. I > > 1) Powered off > 2) Left off for 30 s > 3) Pulled antenna out. > 4) Powered on > 5) Connected antenna, making

Re: [time-nuts] Why is holdover LED on HP 58503A not lit, when GPS lock is unlit too?

It is looking much better now. I 1) Powered off 2) Left off for 30 s 3) Pulled antenna out. 4) Powered on 5) Connected antenna, making sure if was firmly screwed in. It then got GPS lock in a few minutes. It is running at reduced accuracy, with the survey only 9.7% complete, but it is looking

Re: [time-nuts] Why is holdover LED on HP 58503A not lit, when GPS lock is unlit too?

On 18 December 2016 at 18:19, Dan Rae <dan...@verizon.net> wrote: > On 12/18/2016 9:34 AM, Dr. David Kirkby (Kirkby Microwave Ltd) wrote: > >> >> *12 -- ---MODE Survey: 0% >> complete >> &

Re: [time-nuts] Why is holdover LED on HP 58503A not lit, when GPS lock is unlit too?

On 18 December 2016 at 14:31, Tim Shoppa wrote: > A common misconception, is that holdover is the opposite of GPS lock. > Sometimes we might even talk about the two as if we're in one or the other. > But really the power-on state, is that we're in neither holdover or GPS >

Re: [time-nuts] Why is holdover LED on HP 58503A not lit, when GPS lock is unlit too?

On 18 December 2016 at 17:34, Dr. David Kirkby (Kirkby Microwave Ltd) < drkir...@kirkbymicrowave.co.uk> wrote: > But perhaps things have improved, as its not attempting to track 6 > (PRN=15, 2, 21, 25, 26 and 28), whereas before it was attempting to track > just with a PRN of 32.

[time-nuts] Why is holdover LED on HP 58503A not lit, when GPS lock is unlit too?

m (MSL) HEALTH MONITOR . [ OK ] Self Test: OKInt Pwr: OK Oven Pwr: OK OCXO: OK EFC: OK GPS Rcv: OK scpi > Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales

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

On 9 December 2016 at 19:58, BIll Ezell wrote: > Sorry if I'm behind the times, just did a new project that required a pcb, > and ExpressPCB is my go-to vendor for one-off boards. I just noticed they > now provide the low-cost boards (fixed size, 3x5, quantity 3) that I've >

Re: [time-nuts] Need for a document comparing time interval counters

On 21 November 2016 at 21:10, Bob Camp wrote: > Hi > > With both counters running on the same external standard (and no internal > OCXO), the 53230 > beats the 53132 both on frequency and time. It also has slightly better > isolation of the 10 MHz > internals so the “dead zone” at

[time-nuts] Do reflections up/down the antenna cable cause a problem with GPS?

on the antenna/cable/receiver are a problem, then attenuators can improve the match, but of course they reduce the signal level too. A more intelligent, but more difficult solution, is to build a matching network. For that one would need a VNA to measure the impedance in the first place. Dr. David Kirkby

[time-nuts] Need for a document comparing time interval counters

If anyone has the time & inclination, a document comparing different time interval counters would be useful to budding time nuts. There are quite a few different models at prices that are affordable to many. I have had a HP 5370B and a Stanford Research  SR620, but have neither now. I

[time-nuts] Do the HP 5334A & 5335A counter/timers take the same oven oscillator?

manuals would answer at least some of the questions, but I only have access to a mobile phone now, so are hoping that someone might know. In any case, different part numbers might actually work, even if not as stable as the correct OCXO. Dave Dr David Kirkby Managing Director Kirkby Microwave Ltd

[time-nuts] Any reference to many/all ways of measuring frequency?

reasonable travelling expenses. Dr David Kirkby Managing Director Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Chelmsford, Essex, CM3 6DT, United Kingdom Registered in England and Wales as company number 08914892 http://www.kirkbymicrowave.co.uk/ Tel 07910 441670 / +44 7910

Re: [time-nuts] Man with too many clocks.

On 4 Nov 2016 17:48, "Bob Camp" wrote: > > Hi > > The only practical way to set the 10811 or 10544 is with a >= 10 turn pot on the EFC. I > never have worked out just why there are so many instruments that don’t have a pot on > the EFC. > > Bob I'm amazed my 18 GHz HP 5342A

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

On 31 October 2016 at 10:37, Poul-Henning Kamp wrote: > > In message gmail.com>, "Dr. David K > irkby (Kirkby Microwave Ltd)" writes: > > >> > [...] so it might be a relatively cheap way to measure

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

On 31 Oct 2016 06:07, "Poul-Henning Kamp" wrote: > > > In message < canx10hcpa5sozukqe00c5hcm-zrwkblnsojcoljokdriols...@mail.gmail.com>, "Dr. David K > irkby (Kirkby Microwave Ltd)" writes: > > > [...] so it might be a relatively cheap way to measure humidity. > >

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

On 28 October 2016 at 01:05, Poul-Henning Kamp wrote: >The exception is the "cold mirror" type of sensor, which measures the > >dewpoint by cooling a mirror and bouncing a light off it to sense the > >temperature where dew condenses on it. Those are expensive, and they >

Re: [time-nuts] Has anybody checked this? GPSDO in kit

On 22 October 2016 at 17:22, Chris Albertson wrote: > > You have to remember what this thing replaces. In ham radio, some people > are using vacuum tube oscillators with mechanical variable capacitor > tuning. Maybe some advanced rigs use gear drive on the capacitor

Re: [time-nuts] Prologix USB-GPIB Controller

On 10 October 2016 at 09:35, Charles Steinmetz wrote: > Poul-Henning wrote: > > And for voltage references, "pre-owned" is likely to mean "better". >> > > Perhaps, but third-world recyclers are not known for gentle treatment > during the parts removal process. I had some

Re: [time-nuts] Prologix USB-GPIB Controller

feit, they are hardly legal devices. Like Bob Camp said, it is better to pay more money and get a genuine product. Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, co

[time-nuts] What's the best Windows 10 ntp client?

At my amateur radio club we have Internet access via a WiFi dongle with a Pay As You Go card. A Windows 10 PC is only powered up while we are there, so on around 2-4 hours per week.  Does anyone have any thoughts on what might be the most suitable software to run on our Windows 10 PC to set

Re: [time-nuts] Anybody want a Thunderbolt power supply?

Original message From: Charles Steinmetz Date:09/01/2016 06:07 (GMT+00:00) To: time-nuts@febo.com Subject: Re: [time-nuts] Anybody want a Thunderbolt power supply? Randall wrote: > Tested and guaranteed samples of all of these can be bought for $25-100 if you are

Re: [time-nuts] negative mention of products (was: DIY VNA design)

On 22 August 2016 at 23:15, Attila Kinali <att...@kinali.ch> wrote: > On Mon, 22 Aug 2016 16:16:16 +0100 > "Dr. David Kirkby (Kirkby Microwave Ltd)" <drkir...@kirkbymicrowave.co.uk> > wrote: > > > That resulted in the manufacturer of the RigExpert contacti

Re: [time-nuts] DIY VNA design

On 22 August 2016 at 02:51, bownes <bow...@gmail.com> wrote: > > Comment inline > > > > On Aug 21, 2016, at 18:59, Dr. David Kirkby (Kirkby Microwave Ltd) < > drkir...@kirkbymicrowave.co.uk> wrote: > > > > I am not convinced that this is time-nuts rela

Re: [time-nuts] DIY VNA design

On 21 Aug 2016 03:19, "Attila Kinali" wrote: > > Moin, > > I stumbled over a new open hardware/source VNA design: > http://hforsten.com/cheap-homemade-30-mhz-6-ghz-vector-network-analyzer.html > > Unlike other designs out there, this one is very well done and has very > little

Re: [time-nuts] HP5370 power supply measurements

On 13 Jul 2016 08:31, "Charles Steinmetz" wrote: > An external fan blowing on the heatsink keeps my 5370s nice and cool, for about $10 each. So more noise. > *if the counters were operated 24/7/365*. I sometimes take data for a few months straight, but very, very far

Re: [time-nuts] Visiting Greenwich

On 5 Jul 2016 00:43, "Dave Martindale" wrote: > > I am in London England at the moment, playing tourist with the rest of my > family. I want one day to be a visit to the National Maritime Museum at > Greenwich, which includes the Royal Observatory Greenwich. I am >

Re: [time-nuts] Cable length calibration

On 30 June 2016 at 09:19, Scott McGrath wrote: > If the nominal velocity of propagation is known and length is known delay > is easily determined mathematically > Except that coax does not have a uniform impedance or velocity factor. Both will vary as a function of position

Re: [time-nuts] buying a time interval counter

On 29 Jun 2016 17:02, "Stéphane Rey" wrote: > > Hello there, > > I'm planning to buy a such instrument in order to do some frequency stability measurement at work. The SR620 seems to be discontinued. It still looks available to me http://www.thinksrs.com/products/SR620.htm

Re: [time-nuts] Phase noise measurements on the cheap with an Agilent E4406A VSA Transmitter Tester?

On 18 June 2016 at 21:01, John Miles wrote: > > and looked at what was used to make the phase noise measurements. It was > an > > Agilent E4406A. The noise floor is nowhere near as low as the more > > expensive instruments, but the E4406A is available for under $500, which > is >

[time-nuts] Phase noise measurements on the cheap with an Agilent E4406A VSA Transmitter Tester?

I was looking at some high end commercial low noise oscillators and see they use instrument like the Agilent E5052B signal source analyzer for phase noise measurements. When I looked for them on eBay, it soon because apparently they were very expensive. Then I see this oscillator that locks to

Re: [time-nuts] How can I generate a very clean 1 W signal @ 116 MHz ?

On 30 May 2016 17:01, "Richard (Rick) Karlquist" <rich...@karlquist.com> wrote: > > On 5/30/2016 4:06 AM, Dr. David Kirkby (Kirkby Microwave Ltd) wrote: >> I'm wondering what's the best way to generate 116 MHz with very low phase >> noise. Phase noise at < 20

[time-nuts] How can I generate a very clean 1 W signal @ 116 MHz ?

I was thinking about designing a 2 m (144-146 MHz) ->HF (28-30 MHz) transverter, using a 116 MHz local oscillator feeding a level 30 mixer. 116 + 28 = 144 116 + 30 = 146 I'm wondering what's the best way to generate 116 MHz with very low phase noise. Phase noise at < 20 kHz offset is

Re: [time-nuts] NPL open day

going. Say hello if you see me. Dr David Kirkby Managing Director Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Chelmsford, Essex, CM3 6DT, United Kingdom Registered in England and Wales as company number 08914892 http://www.kirkbymicrowave.co.uk/ Tel 07910 441670 / +4

Re: [time-nuts] Using lasers for data transmission

On 1 May 2016 15:02, "Bruce Griffiths" wrote: > > The solution with high power is to use a beam expander so that the unaided eye cannot collect a power greater than the safe limit. Using near IR beams also helps. > Bruce It is a long time since I worked with lasers,

Re: [time-nuts] Using lasers for data transmission

> Hi, > Several (many?) years ago National Geographic magazine show a picture taken here in southern California of the state government sending red laser signals between different mountain tops to keep track what was going on near fault lines > There were no technical details on what was taking

Re: [time-nuts] RG6 or LMR400 for GPS Antenna (Symmetricom 58532A and T-bolt)

On 21 Apr 2016 01:00, "Bob Camp" wrote: > > Hi > > RG-6 Quad Shield should be fine as long as it’s meeting the published specs. The advantage of LRM-400 is that you likely *know* where it came from and what the specs are. There is plenty of coax marked LMR400 that is produced in

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