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

Am Tue, 10 Apr 2018 17:43:25 +1200 schrieb donald collie : > I`ve just bought two GPSDO`s from China @ US$9-50 each [This is not an > error!] They are stated as being new, and use a Trimball dual oven > OCXO. I plan to run these in parallel [2 antennas, 2 feedlines, and 2

Re: [time-nuts] Can I haz an anti-hydrogen maser now?

The obvious trick would be to choose their distance such that only their noise cancels... SCNR, Florian Am Sat, 5 Aug 2017 01:09:00 +0100 schrieb Adrian Godwin : > Don't put it anywhere near your hydrogen maser or they'll cancel each > other out. > > > On Sat, Aug 5, 2017

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

Am Thu, 13 Oct 2016 17:57:02 -0500 schrieb "Graham / KE9H" : > Actually, if they have the "CE" stamp on the product, then they have > very specific radio interference limits that they must test and meet. > It must have been tested, certified, and the certification package >

Re: [time-nuts] Cable length calibration

Am Wed, 29 Jun 2016 12:28:50 -0700 schrieb Hal Murray : > > bro...@pacific.net said: > > At one point they were looking into making a GPS time receiver > > where the cable length calibration would be built-in. > > How would you do that? > > The obvious way is to

Re: [time-nuts] Temperature controlled TCVCXO

Am Fri, 13 May 2016 20:28:04 -0500 schrieb David : > It figures that HP would have done this if anybody had. I am not that > familiar with their design history so thanks for bringing this to my > attention. > > I did not find anything in the theory section of the original

Re: [time-nuts] 1 PPS 50-ohm driver

Am Mon, 18 Apr 2016 18:15:22 -0400 schrieb Bob Camp : > Hi > > If our approach was to fabricate an IC totally from scratch for this > or that application, there are a lot of things that could be done. > Unfortunately, for most of us, doing that to wire up an output on a > board …

Re: [time-nuts] 1 PPS 50-ohm driver

Am Sun, 17 Apr 2016 23:03:11 +0200 schrieb Gerhard Hoffmann : > Am 17.04.2016 um 16:59 schrieb Wojciech Owczarek: > > A slightly naive question(s) perhaps, so do excuse me, but I reckon > > this is a good opportunity to ask since I am approaching the same > > design questions

Re: [time-nuts] Reliability of atomic clocks

Am Mon, 28 Mar 2016 03:20:14 + schrieb Mark Sims : > > Mil-spec parts would be somewhat more reliable than commercial > > parts. > Actually, that is seldom true. The main difference between mil-spec > parts and commercial parts tends to be in the post-packaging device

Re: [time-nuts] Meaning of MTBF (was: Reliability of atomic clocks)

Am Mon, 28 Mar 2016 01:32:03 +0200 schrieb Attila Kinali : > Yes, the MTBF is a very simplicistic measure and there are a couple > of assumptions in its calculation which do not hold generally (or > rather, it's rather seldom that they hold). Yet it gives a number to > something

Re: [time-nuts] Calibration procedures - what is normal?

Am Sat, 13 Feb 2016 18:41:02 +1300 schrieb "Dave Brown" : > Cobham is a UK based defence and high end security supplier- > originally formed (not too many years ago) by their buying out of > several other companies in their lines of business. More recently > they have got

Re: [time-nuts] modern electronics education/jobs (was:

Am Thu, 12 Nov 2015 18:14:57 -0800 schrieb "Richard (Rick) Karlquist" : > > > On 11/12/2015 1:01 PM, William Schrempp wrote: > > > > has failed. I hear old machinists complaining about new machinists > > who can't drill a hole if the drill-press isn't > >

Re: [time-nuts] Beginners GPS locked frequency counter question

Am Sat, 31 Oct 2015 10:50:36 + schrieb Chris Wilson : > > > 31/10/2015 10:46 > >I have a Racal counter locked to 1 MHz on its rear panel external >input socket from my Trimble Thunderbolt GPS. I derive the 1 Mhz >from a David Partridge divider board. If

Re: [time-nuts] When NTP goes wrong...

Am Sun, 25 Oct 2015 13:34:43 + schrieb Wojciech Owczarek : > I think this is a classic case of confusing application security with > network security. The whole idea relies on spoofing packets. A > spoofing scenario is only realistic in a lab setting. Or in case of a

Re: [time-nuts] When NTP goes wrong...

Am Sun, 25 Oct 2015 07:14:24 + schrieb "Poul-Henning Kamp" <p...@phk.freebsd.dk>: > > In message <20151024123614.7bbfe...@aluminium.mobile.teply.info>, > Florian Teply writes: > > >But if I read that article on ars technica correctly, i

Re: [time-nuts] When NTP goes wrong...

Am Wed, 21 Oct 2015 22:54:15 -0700 schrieb Rob Seaman : > Mark Sims said: > > > Ars Technica just put up a piece on the effects of various attacks > > on NTP with a link to the original paper. > > > >

Re: [time-nuts] UPS for my time rack

Am Tue, 13 Oct 2015 18:54:58 + schrieb "Poul-Henning Kamp" : > > In message <4FD0F30EBAEF49609DF207E3EE61C15B@pc52>, "Tom Van Baak" > writes: > > > >I used to rely on one massive UPS (along with natural gas generator) > >for my entire lab. Eventually I found it

Re: [time-nuts] TTi TF930/960 linux programming

(and there isn't much to it) you can set up a more robust software system. That's exactly what I'm planning to do. In the end it will always need some sort of testing it out anyways. Thanks for sharing in any case. Florian James -Original Message- From: Florian Teply use

[time-nuts] TTi TF930/960 linux programming

Hi guys, I seem to recall that someone on this list mentioned that he's using a Thurlby-Tandar TF930 or 960 Frequency counter. As I'm considering to buy such a unit for some experiments at my workplace, I figured I'd better ask around here for some suggestions. Has someone already used one of

Re: [time-nuts] Harmonics suppression in ring oscillators

Am Thu, 19 Mar 2015 22:26:15 +0100 schrieb Attila Kinali att...@kinali.ch: Moin, On Thu, 19 Mar 2015 21:50:03 +0100 Florian Teply use...@teply.info wrote: My guess would be slightly different: the fundamental mode of oscillation could be considered the lowest energy state of all

Re: [time-nuts] Harmonics suppression in ring oscillators

Am Thu, 19 Mar 2015 14:17:58 +0100 schrieb Attila Kinali att...@kinali.ch: On Wed, 18 Mar 2015 21:19:55 +0100 Florian Teply use...@teply.info wrote: Good, I am not alone.. I felt stupid not being able to find something this basic. Maybe we are stupid not being able to find

Re: [time-nuts] Harmonics suppression in ring oscillators

Am Wed, 18 Mar 2015 09:23:27 +0100 schrieb Attila Kinali att...@kinali.ch: On Tue, 17 Mar 2015 22:04:49 +0100 Florian Teply use...@teply.info wrote: funnily I stumbled across that very question just a few weeks ago while doing my very first ring oscillator designs myself. Good, I am

Re: [time-nuts] Harmonics suppression in ring oscillators

Hi, funnily I stumbled across that very question just a few weeks ago while doing my very first ring oscillator designs myself. The explanation I have come to is essentially the following: In principle, you're right, a ring oscillator CAN oscillate at a number of frequencies. Given the way the

Re: [time-nuts] New WWVB modulation format receivers (NOT)

Am Fri, 21 Feb 2014 11:42:05 -0800 (PST) schrieb Bob Albert bob91...@yahoo.com: Oops yes I goofed, it's 500 MHz.  500 GHz is beyond state of the art I would think. Depends on your circuit development skills. Bipolars with gain at 500GHz are in principle possible, both in III/V-semiconductors

Re: [time-nuts] New WWVB modulation format receivers (NOT)

that the computing shouldn't be an issue for anything nowadays. Why bother with a hardware solution when software can do it more easily? Nuts answer: because we can? Florian -Chuck Harris Florian Teply wrote: Well, if someone comes up with a circuit, I could check how much chip area that would

Re: [time-nuts] New WWVB modulation format receivers (NOT)

Am Wed, 19 Feb 2014 22:45:56 -0800 schrieb Richard (Rick) Karlquist rich...@karlquist.com: On 2/19/2014 9:10 PM, John Marvin wrote: I guess my question is who has the right to grant exclusive rights for the ability to decode a very simple protocol? Was a patent actually granted for

Re: [time-nuts] Yb clock - stability estimation procedure?

Am Mon, 26 Aug 2013 07:56:51 -0400 schrieb Bob Camp li...@rtty.us: Hi On Aug 26, 2013, at 2:01 AM, Magnus Danielson mag...@rubidium.dyndns.org wrote: On 08/25/2013 08:25 PM, Bob Camp wrote: Hi The most common approach is to *assume* that the two devices are not correlated.

Re: [time-nuts] Multiple Time Interval Counters to measure Transients?

Am Sun, 09 Sep 2012 02:40:23 +0200 schrieb Magnus Danielson mag...@rubidium.dyndns.org: Hi Florian, On 09/08/2012 07:34 PM, Florian Teply wrote: The idea I have right now is employing something on the order of three to five comparators per output, fed with different trigger levels

Re: [time-nuts] Multiple Time Interval Counters to measure Transients?

Hello, Am Sat, 8 Sep 2012 21:56:45 +0200 (CEST) schrieb Marek Peca ma...@duch.cz: Well, for the CMOS stuff 100ps should do just fine. Of course, less is better, but there's only so much one can reasonably do for so many channels... Even a PICTIC should be able to do better than 500 ps for

[time-nuts] Multiple Time Interval Counters to measure Transients?

Hi fellow time nuts, quite soon I'll have to come up with a clever idea to characterize a few chips of a 130nm BiCMOS technology for transients. Unfortunately, I'll have to look at something on the order of five dozen outputs per chip, all at the same time. If money and development time was no

Re: [time-nuts] Multiple Time Interval Counters to measure Transients?

Hello, Am Sat, 8 Sep 2012 19:41:28 +0200 (CEST) schrieb Marek Peca ma...@duch.cz: (..) But then I'll have to throw a few hundred Time Interval Counters at the problem in order to get the information on the duration of the transients. So in general, amplitude information comes from the

Re: [time-nuts] broadband MPX signal stereo

Am Thu, 15 Mar 2012 22:08:12 +0100 schrieb Azelio Boriani azelio.bori...@screen.it: Yes, there is people who have what in the past was expensive test equipment and now can be bought by 1/10 of the original price. The problem is that you need someone who can record 2 seconds of a signal that

Re: [time-nuts] Looking for an IEEE paper

On Saturday 05 June 2010 23:55:15 John Miles wrote: Many thanks - I ended up with a couple of copies. :) That's why i announced it on-list as well ;-) Regards, Florian signature.asc Description: This is a digitally signed message part. ___

Re: [time-nuts] Looking for an IEEE paper

On Saturday 05 June 2010 11:29:03 John Miles wrote: I'm interested in tracking down a copy of Walls's Cross-Correlation Phase Noise Measurements from the 1992 IEEE Frequency Control Symposium proceedings, but apparently the IEEE's no longer offering their traditional $10 a la carte downloads.

Re: [time-nuts] OT - GPS and North

Am Saturday 21 November 2009 15:05:12 schrieb iov...@inwind.it: Does a stationary (not in motion) GPS receiver know where the North is? As far as I can understand, it doesn't, isn't it? Umm, as far as i understand it, a single receiver with a single omnidirectional antenna (at least with

Re: [time-nuts] OT - GPS and North

Am Saturday 21 November 2009 20:32:11 schrieb J. Forster: OK. Sme GPS receivers have magnetic sensors. What do they do with/about magnetic deviation. Just a wild guess: The GPS receiver also knows its location, and magnetic deviation is known to some degree in its variation over earth's

Re: [time-nuts] Adret 4101A, the DCF77 and a good antenna

Am Wednesday 21 October 2009 01:16:55 schrieb Alan Melia: Marco, have you considered that HBG on 75.0kHz might be stronger with you from Switzerland??. In a lab or other complex quite often with off-air standards the problem is local noise. I have a friend in Porto who used to be able to lock

Re: [time-nuts] Gold plating on aluminum

Am Tuesday 20 October 2009 21:01:06 schrieb Corby Dawson: Hi, I am working on a project to plate the lamp reflector in an HP 5065A with gold. The existing reflector is aluminum. What little I can find suggests that in addition to some preliminary plating the layer just below the gold should

Re: [time-nuts] time-nuts Digest, Vol 63, Issue 52

Am Sunday 11 October 2009 16:57:50 schrieb Arnold Tibus: On Sun, 11 Oct 2009 16:27:32 +0200, Arnold Tibus wrote: When used these numbers in calculations we anyway have to convert these ppm, ppb, ppt etc. to scientific numbers using exponents There are too often discussions and

Re: [time-nuts] GPS antenna and lightning

Am Sunday 04 October 2009 10:57:22 schrieb kevin-use...@horizon.com: Consider a lightning strike to be the closest thing to an ideal current source you are going to encounter. You *cannot* stop it with series impedance alone, no matter how high; you have to provide it with a very low shunt

Re: [time-nuts] GPS antenna and lightning

Am Sunday 04 October 2009 12:43:16 schrieb Rex: Kevin, That is a very informative description. I've not lived in a lightning-probable area with antennas. Here lightining is a remote possibility, but I'm trying to digest what you have told us. You said, For example, if you have equipment

Re: [time-nuts] GPS antenna and lightning

Am Saturday 26 September 2009 14:44:52 schrieb Robert Vassar: Nothing will save you from a direct strike. At least nothing you can likely afford. You're more likely to get clobbered by a surge from the grid, or induced voltage from a nearby strike. Use the box method. Draw a diagram of