Re: [time-nuts] Paywall rant

Both ACM and IEEE are publishers at heart. IEEE likes to boast that they publish almost a third of the world's technical literature. It's instructive to look at their annual reports, where sources and uses of funds are documented. Follow the money, always. Joe Gwinn Ref:

Re: [time-nuts] wwvb weak on east coast especially when the pre-amps under water.

time-nuts-boun...@febo.com wrote on 05/14/2012 05:04:13 PM: > From: paul swed > To: Discussion of precise time and frequency measurement n...@febo.com> > Date: 05/14/2012 05:04 PM > Subject: Re: [time-nuts] wwvb weak on east coast especially > when the pre-amps under water. > Sent by: time-n

Re: [time-nuts] Question about precise frequency / phase measurement

The traditional approach was to use a double-balanced mixer configured as a phase detector, pass the phase detector output through a low-pass filter (with 1 Hz bandwidth), and plot the result using a chart recorder. The chart recorder would also have marks from some kind of accurate clock. After

Re: [time-nuts] Missing parts of threads

The usual cause of causality problems is senders' mis-set local computer clocks. The rest of the email system believes the header date and time. Joe Gwinn From: "David C. Partridge" To: "'Discussion of precise time and frequency measurement'" Date: 04/18/2012 09:22 AM

Re: [time-nuts] Best location for a GPS antenna...?

I think I know why. I worked on such computers, and they were very sensitive to ESD. If you touched the cabinet during the winter, when it's very dry, the spark would be enough to crash the computer, although permanent damage was rare. The problem was that the computers were under-designed back

Re: [time-nuts] Distribution amp - Use a video amp unit ?

I have seen National LMH6702 current-feedback video amplifier chips in non-inverting amplifier configuration used to implement a wideband 10 MHz distribution amplifier. Joe From: "Charles P. Steinmetz" To: Discussion of precise time and frequency measurement Date: 03/27/

Re: [time-nuts] Distribution amp - Use a video amp unit ?

It would be interesting if the FTS-1050A curves were also plotted. Joe From: John Ackermann N8UR To: Discussion of precise time and frequency measurement Date: 03/25/2012 03:54 PM Subject:Re: [time-nuts] Distribution amp - Use a video amp unit ? Sent by:t

Re: [time-nuts] Neutrinos not so fast? (defective connector)

Björn, time-nuts-boun...@febo.com wrote on 02/23/2012 04:53:06 PM: > From: b...@lysator.liu.se > To: "Discussion of precise time and frequency measurement" > > Date: 02/23/2012 04:53 PM > Subject: Re: [time-nuts] Neutrinos not so fast? (defectove connector) > Sent by: time-nuts-boun...@febo.co

Re: [time-nuts] Neutrinos not so fast? (defectove connector)

A possible mechanism occurs to me. High-precision GPS is very vulnerable to multipath errors. A loos connector will have a significant reflection. The reflected energy will propagate backwards, and be reflected off the transmitter output discontinuity, the twice-reflected energy propagating back

Re: [time-nuts] ebay warning

With any luck, these same guys had worked in the factory that made the cell phones in question. Joe From: Jim Cotton To: time-nuts@febo.com Date: 02/21/2012 03:17 PM Subject:Re: [time-nuts] ebay warning Sent by:time-nuts-boun...@febo.com In an electronics mall (on

Re: [time-nuts] Why a 10MHz sinewave output?

As mentioned below, the propagation speed of the various harmonics varies. What also varies is the temperature coefficient of propagation speed. This, taken with imperfect impedance matches, yields complicated variation of zero-crossing times with temperature. The tempcos are particularly large be

Re: [time-nuts] Epoch rollover?

The last rollover was in August 1999, just before Y2K, and the next rollover will be in April 2019. From: "Bruce Lane" To:

Re: [time-nuts] Did the FCC put LightSquared on ice?

Under FCC rules, receivers have an economic lifetime, so if one makes changes slowly enough, it's OK. (I worked for the FCC in the 1970s.) From: Chuck Forsberg WA7KGX N2469R

Re: [time-nuts] DDS'ery narrow scoped.

May Google be with you: A search on the title and an author yielded: From: Luis Cupido

Re: [time-nuts] 60hz disciplined watch

time-nuts-boun...@febo.com wrote on 04/20/2011 10:38:41 AM: > From: > > cook michael > > To: > > time-nuts@febo.com > > Date: > > 04/20/2011 10:39 AM > > Subject: > > Re: [time-nuts] 60hz disciplined watch > > Sent by: > > time-nuts-boun...@febo.com > > > > > Le 20/04/2011 16:17, Joh

Re: [time-nuts] Upgrading TS2100 from TCXO to OCXO

There are some hidden configuration parameters in the TS2100 that vary by oscillator type (between TCXO,OCXO, and Rb), and include some control loop parameters. It matters a lot that the firmware uses the correct algorithm and parameters. The Rubidiums are quite far from the crystals, but I a

Re: [time-nuts] Why .30 cal holes can't be seen at 800 yds...

time-nuts-boun...@febo.com wrote on 11/03/2010 05:55:16 PM: > From: > > "William H. Fite" > > To: > > Discussion of precise time and frequency measurement > > Date: > > 11/03/2010 05:55 PM > > Subject: > > Re: [time-nuts] Why .30 cal holes can't be seen at 800 yds... > > Sent by: > > t

Re: [time-nuts] A real world project need for timing accuracy...

I have to ask why a simple optical pulse link would not work. For example, fire a 1 ms pulse from the target area towards the firing area when the bullet arrives at the target. The firing area electronics hears the shot and times to the arrival of the optical pulse from the target. Dischargin

Re: [time-nuts] Steve's new QTH...

time-nuts-boun...@febo.com wrote on 09/07/2010 02:57:07 PM: > From: > > Hal Murray > > To: > > Discussion of precise time and frequency measurement > > Date: > > 09/07/2010 03:15 PM > > Subject: > > Re: [time-nuts] Steve's new QTH... > > Sent by: > > time-nuts-boun...@febo.com > > >

Re: [time-nuts] Phase noise measurement (Levinzon cite)

There is a critical typo below: The author's name is "Levinzon", not "Levinson", the s becoming a z. The rest of the cite is correct. time-nuts-boun...@febo.com wrote on 08/21/2010 08:03:46 AM: > From: > > ewkeh...@aol.com > > To: > > time-nuts@febo.com > > Date: > > 08/21/2010 08:04 AM

Re: [time-nuts] surface mount (was PICTIC II Parts from Mouser)

It's amazing what one can do by hand. In the 1970s I worked in an electrophysiology lab where we put glass microelectrodes into rat neurons. The microelectrodes were made in the lab by heating 1 mm diameter glass tubing to an orange heat and pulling abruptly. (This was done in a simple machi

Re: [time-nuts] Long period variation of GPS PPS timing?

time-nuts-boun...@febo.com wrote on 07/01/2010 02:01:25 PM: > From: > > Paul Nicholson > > To: > > Discussion of precise time and frequency measurement > > Date: > > 07/01/2010 02:02 PM > > Subject: > > Re: [time-nuts] Long period variation of GPS PPS timing? > > Sent by: > > time-nuts

Re: [time-nuts] Long period variation of GPS PPS timing?

time-nuts-boun...@febo.com wrote on 07/01/2010 12:06:54 PM: > From: > > Paul Nicholson > > To: > > Discussion of precise time and frequency measurement > > Date: > > 07/01/2010 12:08 PM > > Subject: > > Re: [time-nuts] Long period variation of GPS PPS timing? > > Sent by: > > time-nuts

Re: [time-nuts] Microphonic Inductor?

Said, time-nuts-boun...@febo.com wrote on 04/13/2010 12:49:05 PM: > From: > > saidj...@aol.com > > To: > > time-nuts@febo.com > > Date: > > 04/13/2010 12:54 PM > > Subject: > > Re: [time-nuts] Microphonic Inductor? > > Sent by: > > time-nuts-boun...@febo.com > > Hi there, > > I do hav

Re: [time-nuts] need help with LPF

Said, time-nuts-boun...@febo.com wrote on 04/12/2010 09:10:36 PM: > From: > > saidj...@aol.com > > To: > > time-nuts@febo.com > > Date: > > 04/12/2010 09:13 PM > > Subject: > > Re: [time-nuts] need help with LPF > > Sent by: > > time-nuts-boun...@febo.com > > Hi Joe/Bob, > > the board

Re: [time-nuts] need help with LPF

Said, time-nuts-boun...@febo.com wrote on 04/12/2010 07:42:39 PM: > From: > > saidj...@aol.com > > To: > > time-nuts@febo.com > > Date: > > 04/12/2010 07:52 PM > > Subject: > > [time-nuts] need help with LPF > > Sent by: > > time-nuts-boun...@febo.com > > > Hello guys, > > need some

Re: [time-nuts] OT Question - Surplus Places

There is also Young Engineering in Salem, Mass. < http://www.youngengsales.com/> They used to have more electronics stuff, but they seem to have become a used machine tool dealer. Well, the electronics stuff may be too numerous and cheap to be worth listing on the website. time-nuts-boun...@f

Re: [time-nuts] HP 5065A rubidium lifetime (soldering kovar)

time-nuts-boun...@febo.com wrote on 03/21/2010 10:43:40 PM: > From: > > Bob Camp > > To: > > Discussion of precise time and frequency measurement > > Date: > > 03/21/2010 10:52 PM > > Subject: > > Re: [time-nuts] HP 5065A rubidium lifetime > > Sent by: > > time-nuts-boun...@febo.com >

Re: [time-nuts] frying pan antenna

> > Sent by: > > time-nuts-boun...@febo.com > > Joseph M Gwinn wrote: > > The tar paper is there primarily to reduce air infiltration when the wind > > blows. Now days this purpose is served by the white housewrap, the > > original brand being Tyvek. > >

Re: [time-nuts] frying pan antenna

The tar paper is there primarily to reduce air infiltration when the wind blows. Now days this purpose is served by the white housewrap, the original brand being Tyvek. Water that blows past the shingles is stopped by the tarpaper or housewrap, keeping the sheathing and insulation dry. Fr

Re: [time-nuts] Thermal time constant

A better metric may be stored heat for a dollar's worth of material. Scrap iron is pretty cheap. From: Bob Camp To: Discussion of precise time and frequency measurement Date: 03/10/2010 06:03 PM Subject: Re: [time-nuts] Thermal time constant Sent by: time-nuts-boun...@febo.com Hi The got

Re: [time-nuts] DMTD Mixer Terminations

time-nuts-boun...@febo.com wrote on 03/03/2010 10:56:46 PM: > From: > > Bruce Griffiths > > To: > > Discussion of precise time and frequency measurement > > Date: > > 03/03/2010 11:03 PM > > Subject: > > Re: [time-nuts] DMTD Mixer Terminations > > Sent by: > > time-nuts-boun...@febo.co

Re: [time-nuts] Vremya-ch Hydrogen Masers

time-nuts-boun...@febo.com wrote on 03/02/2010 04:51:15 PM: > From: > > "Bob Camp" > > To: > > "'Discussion of precise time and frequency measurement'" n...@febo.com> > > Date: > > 03/02/2010 04:55 PM > > Subject: > > Re: [time-nuts] Vremya-ch Hydrogen Masers > > Sent by: > > time-nuts-

Re: [time-nuts] No 1 PPS output on a Tbolt

The 1PPS signal is actually quite strong. I would hook a telephone receiver or perhaps a little speaker to the 1PPS output and listen. The signal should make an audible click once per second. Joe Gwinn time-nuts-boun...@febo.com wrote on 02/08/2010 12:01:46 PM: > From: > > Mark Sims > >

Re: [time-nuts] Triangle Waves

> > Sent by: > > time-nuts-boun...@febo.com > > Joseph M Gwinn wrote: > > time-nuts-boun...@febo.com wrote on 02/02/2010 08:19:26 PM: > > > > > >> From: > >> > >> Bruce Griffiths > >> > >> To: > >> > >&g

Re: [time-nuts] Triangle Waves

> > Sent by: > > time-nuts-boun...@febo.com > > Joseph M Gwinn wrote: > > time-nuts-boun...@febo.com wrote on 02/02/2010 07:20:24 PM: > > > > > >> From: > >> > >> Bruce Griffiths > >> > >> To: > >> > >&g

Re: [time-nuts] Triangle Waves

time-nuts-boun...@febo.com wrote on 02/02/2010 07:20:24 PM: > From: > > Bruce Griffiths > > To: > > Discussion of precise time and frequency measurement > > Date: > > 02/02/2010 07:27 PM > > Subject: > > Re: [time-nuts] Triangle Waves > > Sent by: > > time-nuts-boun...@febo.com > > Ma

Re: [time-nuts] Variable Conductance Heat Pipes for temperature control

I have the book now. The VHCP used to control the temperature of a Cesium (not Rubidium) clock utilized in a GPS ground station is stated as maintaining clock temperature at 57 C +/- 13 C despite a ambient temperature range of -25 C to +55 C, while handling 5 watts of heat. This is a 3: reduc

Re: [time-nuts] Datum Exactime 9390-6000 question

Rich, Call Symmetricom Tech Support. I'm pretty sure that they produced upgrade PROMs to solve this exact problem. Joe Gwinn From: "Rich Stolte" To: Date: 12/15/2009 03:12 PM Subject: [time-nuts] Datum Exactime 9390-6000 question Sent by: time-nuts-boun...@febo.com I have two Datum 939

Re: [time-nuts] OT: Power level reference

time-nuts-boun...@febo.com wrote on 12/01/2009 07:00:21 PM: > From: > > "J. Forster" > > To: > > "Discussion of precise time and frequency measurement" n...@febo.com> > > Date: > > 12/01/2009 07:10 PM > > Subject: > > Re: [time-nuts] OT: Power level reference > > Sent by: > > time-nuts-

Re: [time-nuts] unités & conventions internationa les

time-nuts-boun...@febo.com wrote on 10/12/2009 04:23:11 PM: > From: > > "Chris Cheney" > > To: > > Discussion of precise time and frequency measurement > > Date: > > 10/12/2009 04:31 PM > > Subject: > > Re: [time-nuts] unités & conventions internationales > > Sent by: > > time-nuts-b

Re: [time-nuts] unités & conventions internationa les

While Britain and Europe may agree on the definition of "billion" (a million million), the US differs (a thousand million). So, IEEE standards use "one thousand million" and do not use billion. Joe Gwinn From: "Arnold Tibus" To: "Discussion of precise time and frequency measurement" , "j.

Re: [time-nuts] Fundamental limits on performance

only that they bake and evacuate the envelope after assembly and hermetic sealing, unless the tip-off tube is *very* large. Joe Gwinn > Rick > > > Joseph M Gwinn wrote: > > Rick, > > > > > > time-nuts-boun...@febo.com wrote on 09/17/2009 01:10:32 PM: > >

Re: [time-nuts] Fundamental limits on performance

Rick, time-nuts-boun...@febo.com wrote on 09/17/2009 01:10:32 PM: > From: > > "Rick Karlquist" > > To: > > "Discussion of precise time and frequency measurement" n...@febo.com> > > Date: > > 09/17/2009 01:20 PM > > Subject: > > Re: [time-nuts] Fundamental limits on performance > > Sent

Re: [time-nuts] Difference in GPS antennas

Bob, time-nuts-boun...@febo.com wrote on 08/14/2009 01:05:34 PM: > From: > > Robert Darlington > > To: > > Discussion of precise time and frequency measurement > > Date: > > 08/14/2009 02:06 PM > > Subject: > > Re: [time-nuts] Difference in GPS antennas > > Sent by: > > time-nuts-bou

Re: [time-nuts] Method for comparing oscillators

Rex, time-nuts-boun...@febo.com wrote on 08/04/2009 07:35:51 PM: > From: > > Rex > > To: > > Discussion of precise time and frequency measurement > > Date: > > 08/04/2009 07:43 PM > > Subject: > > Re: [time-nuts] Method for comparing oscillators > > Sent by: > > time-nuts-boun...@feb

Re: [time-nuts] Measuring phase shift between 1 Hz DMTD signals by I+Q processing

Magnus, time-nuts-boun...@febo.com wrote on 07/27/2009 12:53:19 AM: > From: > > Magnus Danielson > > To: > > Discussion of precise time and frequency measurement > > Date: > > 07/27/2009 12:56 AM > > Subject: > > Re: [time-nuts] Measuring phase shift between 1 Hz DMTD signals > by I+Q

Re: [time-nuts] OT Euro/US plumbing was 14 tpi UNS die

time-nuts-boun...@febo.com wrote on 07/07/2009 05:38:52 PM: > From: > > b...@lysator.liu.se > > To: > > "Discussion of precise time and frequency measurement" n...@febo.com> > > Date: > > 07/07/2009 05:40 PM > > Subject: > > [time-nuts] OT Euro/US plumbing was 14 tpi UNS die > > Sent by:

Re: [time-nuts] Thunderbolt stability and ambient temperature

ine bottles in the bottom of the cooler as thermal masses. Sadly, any bottle showing any signs of leakage whatsoever will have to be replaced, the leaking bottle being uncorked and the contents tested. At length. Joe Gwinn > > > On 16/06/2009, at 2:30 AM, Joseph M Gwinn wrote: > &

Re: [time-nuts] Pre-industrial timekeeping accuracy RE: Lifetime of glass containers

time-nuts-boun...@febo.com wrote on 06/15/2009 05:49:35 PM: > > > -Original Message- > > From: time-nuts-boun...@febo.com > > [mailto:time-nuts-boun...@febo.com] On Behalf Of J. Forster > > Sent: Monday, June 15, 2009 2:34 PM > > To: Discussion of precise time and frequency measurement >

Re: [time-nuts] Lifetime of glass containers

time-nuts-boun...@febo.com wrote on 06/15/2009 03:56:42 PM: > Not to charge in, but I've looked at ordinary window pane glass in very old > buildings and you can actually see the rippling effect that occurred over > time, showing the "flow" of the glass toward the lower edge of the pane. One

Re: [time-nuts] Thunderbolt stability and ambient temperature

time-nuts-boun...@febo.com wrote on 06/15/2009 06:57:13 AM: > They suggest you add a small amount of chlorine bleach to water > containers you store for natural disaster emergencies. You also need > to replace the water on a regular basis even with the bleach in it. > Here in Christchurch, New Zea

Re: [time-nuts] Thunderbolt stability and ambient temperature

time-nuts-boun...@febo.com wrote on 06/10/2009 07:23:56 PM: > Joseph M Gwinn wrote: > > > I read somewhere the suggestion to take the cast iron block > from an old > > automobile engine and put it in a heavy insulated wooden > cabinet: ~250 Kg > > of iron in an

Re: [time-nuts] Thunderbolt stability and ambient temperature

time-nuts-boun...@febo.com wrote on 06/10/2009 03:13:19 AM: > In message <4a2efc6d.4020...@xtra.co.nz>, Bruce Griffiths writes: > > Bruce, > > >>> The thermal time constant (not the thermal impedance per se) is what > >>> matters [...] > > That is pretty much exactly the (mis-)definition of the

Re: [time-nuts] PCI IRIG receiver card for AIX?

time-nuts-boun...@febo.com wrote on 05/28/2009 11:08:31 AM: > And depending on what you mean by "industrial grade", they also have > the bc635 board in a CompactPCI form-factor, too. Or at least they > used to some years ago. I remember that card from 1995! The BC635 would be suitable. If stil

Re: [time-nuts] PCI IRIG receiver card for AIX?

time-nuts-boun...@febo.com wrote on 05/27/2009 10:43:18 PM: > > Does anybody know of any PCI cards that will receive IRIG-B time > > signals and come with an I/O driver for AIX (IBM's flavor of UNIX)? > > Industrial-grade commercial products are preferred. > > In the past I have, on one occasio

Re: [time-nuts] Solartron 7081 ROMs

time-nuts-boun...@febo.com wrote on 04/29/2009 03:50:12 PM: > I'm sure there was a message on this group a month or two ago, > where the bottom > line was to read the EPROMs with a slightly lower than usual voltage. Look up "schmoo plots", which are used to determine the temperature by supply v

Re: [time-nuts] Spring cleaning and antenna placement

time-nuts-boun...@febo.com wrote on 04/13/2009 11:32:48 AM: > bro...@pacific.net skrev: > > Hi Magnus: > > > > Why not just put the GPS antenna at the top of the existing TV mast? > > http://www.prc68.com/I/Ant.shtml#SBant > > It would be a little bit of a challenge... I think I have some 4-5 me

Re: [time-nuts] Frequency Divider

time-nuts-boun...@febo.com wrote on 04/02/2009 06:00:17 PM: > Hal Murray wrote: > >> LVDS may be useful for frequency distribution between circuit boards. > >> > > > > Good idea thanks. > > > > Receivers designed for LVDS are probably good even if the > input signal is > > single ended. Just c

Re: [time-nuts] GPS Jamming Trials..

The simpler way to prevent mangling of URLs is to put corner brackets < ... > around the URL. This lets the email reader know where the URL starts and ends. So, for instance: < http://tl.gpsworld.com/gpstl/Latest+News/Maritime-Jamming-Trial-Shows-GPS-Vulnerabilities/ArticleStandard/Article/det

[time-nuts] Rubiola on Mixers

A while back, there was a discussion on how best to use double balanced diode ring mixers for delay measurements. I came upon a very useful paper by Enrico Rubiola: "Tutorial on the double balanced mixer", Enrico Rubiola, 21 Aug 2006 , 52 pages, arXiv:physics/0608211v1 [physics.ins-det].

Re: [time-nuts] Wenzel Oscillator Repair

this method wouldn't damage any of the modules, removed or adjacent.) Many epoxies will also creep, especially when hot. Joe > -Chuck Harris > > Joseph M Gwinn wrote: > > Chuck, > > > > > > time-nuts-boun...@febo.com wrote on 01/21/2009 11:34:41 AM: >

Re: [time-nuts] Wenzel Oscillator Repair

Chuck, time-nuts-boun...@febo.com wrote on 01/21/2009 11:34:41 AM: > Hi Joe, > > Nope, Magnus is talking about foam insulated hermetically sealed > ocxo's. > > The point you are missing is the preheater is only set for a temperature > that the foam, etc. can take on a continuous basis... such

Re: [time-nuts] Wenzel Oscillator Repair

Magnus, time-nuts-boun...@febo.com wrote on 01/20/2009 04:47:26 PM: > Joseph M Gwinn skrev: > > time-nuts-boun...@febo.com wrote on 01/20/2009 04:32:15 PM: > > > >> Bruce Griffiths skrev: > >>> The relatively low thermal conductivity of the steel can will

Re: [time-nuts] Wenzel Oscillator Repair

time-nuts-boun...@febo.com wrote on 01/20/2009 04:32:15 PM: > Bruce Griffiths skrev: > > The relatively low thermal conductivity of the steel can will help > > considerably in avoiding thermal damage if the heat is > applied to the joint. > > If the can were copper it would be much more difficult

Re: [time-nuts] Standards sought for immunity of shielded cable links to power-frequency ground loops

time-nuts-boun...@febo.com wrote on 01/08/2009 03:47:29 AM: > In message 00817...@mck.us.ray.com>, Joseph M Gwinn writes: > > > >Was there a big bang? What was the source of the 600 amps? > > They replaced the separation transformer with a UPS, and they > con

Re: [time-nuts] Standards sought for immunity of shielded cable links to power-frequency ground loops

Magnus, time-nuts-boun...@febo.com wrote on 01/07/2009 10:47:46 PM: > Joseph, > > >>> Could be a differential TX and RX. I recall that they send a RS422 > > signal. > >> Depending on the speed, RS422 works fine with transformers. > > > > Yes. It would be 10 MHz or 20 MHz, depending on codin

Re: [time-nuts] Standards sought for immunity of shielded cable links to power-frequency ground loops

Poul-Henning, time-nuts-boun...@febo.com wrote on 01/07/2009 05:56:19 PM: > In message 007cc...@mck.us.ra > y.com>, Joseph M Gwinn writes: > > >Could be a differential TX and RX. I recall that they send a RS422 signal. > > Depending on the speed, RS422 works fine

Re: [time-nuts] Standards sought for immunity of shielded cable links to power-frequency ground loops

Poul-Henning, time-nuts-boun...@febo.com wrote on 01/07/2009 04:25:04 PM: > In message 00090...@mck.us.ra > y.com>, Joseph M Gwinn writes: > > >The effect of differing ground potentials on a shielded cable is to pull a > >large current through the shield, [...] >

Re: [time-nuts] Standards sought for immunity of shielded cable links to power-frequency ground loops

Magnus, time-nuts-boun...@febo.com wrote on 01/07/2009 01:27:52 AM: > Joseph M Gwinn skrev: > > First the background: > > > > In some timing distribution applications, the primary source of > > interference comes from different ground voltages in different parts of

[time-nuts] Standards sought for immunity of shielded cable links to power-frequency ground loops

First the background: In some timing distribution applications, the primary source of interference comes from different ground voltages in different parts of the facility, such as a ship or a megawatt radar. The effect of differing ground potentials on a shielded cable is to pull a large cur

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/17/2008 06:26:00 PM: [snip] > > > > > > > >> [BG] It isn't necessary to use a pair of mixers and an offset source to > >> characterise the sound card, driving both sound card inputs from the > >> same audio source should suffice. > >> > > > > [JG]

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/17/2008 03:43:16 PM: > Joe > > Joseph M Gwinn wrote: > > Bruce, > > > > > > time-nuts-boun...@febo.com wrote on 12/16/2008 10:21:55 PM: > > [snip] > > > >> [BG] Obtaining suitable mixers for 5MH

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/16/2008 09:05:55 PM: > Joseph M Gwinn wrote: > > Bruce, > > > > > > time-nuts-boun...@febo.com wrote on 12/15/2008 05:31:27 PM: > > > > > >> Joseph M Gwinn wrote: > >> > >>> Br

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/16/2008 10:21:55 PM: > Joe > > Joseph M Gwinn wrote: > > Bruce, > > [snip] > > Bruce wrote: > >> > >> A CB stage probably isn't optimum for the mixer preamp so that lower > >> valu

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/16/2008 08:43:29 PM: > Joe > > Joseph M Gwinn wrote: > > Bruce, > > > > > > time-nuts-boun...@febo.com wrote on 12/15/2008 06:42:59 PM: > > [snip] > >>> > >>> > >> However t

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/15/2008 05:31:27 PM: > Joseph M Gwinn wrote: > > Bruce, > > > > > > time-nuts-boun...@febo.com wrote on 12/15/2008 04:34:34 PM: > > [snip] > > > >> I need to build a noise source to check the abs

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/15/2008 06:42:59 PM: > Joe > Joseph M Gwinn wrote: > > Bruce, > > > > > > time-nuts-boun...@febo.com [Bruce] wrote on 12/15/2008 04:56:26 PM: > > > >>>>> [snip] > >>>>> >

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com [Bruce] wrote on 12/15/2008 04:56:26 PM: > Joe > > Joseph M Gwinn wrote: > > Bruce, > > > > > > time-nuts-boun...@febo.com wrote on 12/11/2008 07:44:01 PM: > > > > [snip] > > > > > >> Usi

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/15/2008 04:34:34 PM: > Joseph M Gwinn wrote: > > Bruce, > > > > > > time-nuts-boun...@febo.com wrote on 12/11/2008 08:36:47 PM: > > > > > >> Joe > >> > >> Attached is noise spectr

Re: [time-nuts] Sub Pico Second Phase logger

F ports are driven by 2 separate OCXOs. > > Detailed in line post follows: > > Bruce > > Joseph M Gwinn wrote: > > Bruce, > > > > > > time-nuts-boun...@febo.com wrote on 12/10/2008 08:38:13 PM: > > > > > >> Joe > >> Joseph M G

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/11/2008 08:36:47 PM: > Joe > > Attached is noise spectrum (1kHz and below) of AP192 with nothing > connected to inputs. > Sampling rate 96KSPS. > Frequency bin equivalent noise bandwidth ~ 3Hz. > Noise has similar spectrum to flicker noise with a no

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, time-nuts-boun...@febo.com wrote on 12/10/2008 08:38:13 PM: > Joe > Joseph M Gwinn wrote: > > Bruce, > > > > > >> Reflecting the sum frequency back into the mixer is actually necessary > >> to reduce the noise at the IF port. > >> I b

Re: [time-nuts] Sub Pico Second Phase logger (Posting Style)

iscussion of precise time and frequency measurement Subject: Re: [time-nuts] Sub Pico Second Phase logger Joe Joseph M Gwinn wrote: > Bruce, > > >> Reflecting the sum frequency back into the mixer is actually necessary >> to reduce the noise at the IF port. >> I believe tha

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, [EMAIL PROTECTED] wrote on 12/10/2008 07:58:49 PM: > Joseph M Gwinn wrote: > > Bruce, > > > > > > [EMAIL PROTECTED] wrote on 12/10/2008 04:46:50 PM: > > > > > >> Joe > >> > >> Another limitation on using too low a beat f

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, [EMAIL PROTECTED] wrote on 12/10/2008 04:46:50 PM: > Joe > > Another limitation on using too low a beat frequency is imposed by the > increasing equivalent input noise spectral density of the sound card as > the frequency decreases. Yes, although people made good use of 1 Hz in DMTD ins

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, [EMAIL PROTECTED] wrote on 12/09/2008 09:20:08 PM: > Joe > > Joseph M Gwinn wrote: > > Bruce, > > > >> A PCB mount mixer package is also preferable as its then much easier to > >> use a capacitive IF port termination (for lower noise) in conjun

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, [EMAIL PROTECTED] wrote on 12/09/2008 07:55:50 PM: > Joseph M Gwinn wrote: > > Bruce, > > > > > > [EMAIL PROTECTED] wrote on 12/09/2008 07:10:55 PM: > > > > > >> Paper with capacitive IF port termination data: > >> > >>

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, [EMAIL PROTECTED] wrote on 12/09/2008 06:24:22 PM: > Joseph M Gwinn wrote: > > Bruce > > > > > > [EMAIL PROTECTED] wrote on 12/08/2008 07:12:22 PM: > > > > [snip] > > > > > >>> Many mixers have IF response down to DC. >

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, [EMAIL PROTECTED] wrote on 12/09/2008 07:10:55 PM: > Paper with capacitive IF port termination data: > > http://tf.nist.gov/timefreq/general/pdf/112.pdf This one is new to me, and interesting. More later, when I've read it. > Phase detector sensitivity to distortion: > > http://tf.n

Re: [time-nuts] Sub Pico Second Phase logger

Bruce [EMAIL PROTECTED] wrote on 12/08/2008 07:12:22 PM: > Joseph M Gwinn wrote: > > Bruce, > > > > > > [EMAIL PROTECTED] wrote on 12/08/2008 05:53:08 PM: > > > > > >> Joseph M Gwinn wrote: > >> > >>> People used passive mix

Re: [time-nuts] Sub Pico Second Phase logger

Bruce, [EMAIL PROTECTED] wrote on 12/08/2008 05:53:08 PM: > Joseph M Gwinn wrote: > > People used passive mixers driving electromechanical stripchart recorders > > to compare high-stability oscillators in the good old days. > > > > One assumes that there is

Re: [time-nuts] Sub Pico Second Phase logger

People used passive mixers driving electromechanical stripchart recorders to compare high-stability oscillators in the good old days. One assumes that there is a purely analog approach to measurement of picosecond changes in delay at 10 MHz using a single oscillator, but I have not seen any met

Re: [time-nuts] GPSDO using 100Hz

[EMAIL PROTECTED] wrote on 11/24/2008 08:31:22 PM: > Bruce wrote: > > Analog time constants of several hours are generally considered > > impractical due to the lack of suitable low noise components > > principally high value resistors and capacitors. > > So how do you propose to get arou

Re: [time-nuts] Do any regulations or laws require tim e to be accurate within ?x? seconds?

[EMAIL PROTECTED] wrote on 11/06/2008 12:07:43 PM: > Thanx for the reply. > > > > I was looking for a reference to s specific amount of time that > clocks needs > to be in sync, i.e., within 10 seconds. You mentioned PCI. > Yes, it requires > synchronization, but in section 10.4, it does not

Re: [time-nuts] Question on crystal jumps

[EMAIL PROTECTED] wrote on 10/23/2008 08:15:01 PM: > Joseph M Gwinn wrote: > > Would SAW oscillators be better than crystals? > > > > Joe > > > > > > > They still rely on using a piezoelectric crystal as does a BAW > oscillator. > There

Re: [time-nuts] Question on crystal jumps

Would SAW oscillators be better than crystals? Joe [EMAIL PROTECTED] wrote on 10/23/2008 07:01:31 PM: > Steve Rooke wrote: > > Hi, > > > > I believe it was pointed out earlier that the output of a LPRO uses > > some form of xtal oscillator as the output of the rubidium stage is > > quite noisy.

Re: [time-nuts] homebrew 13 dBm distribution amplifier based on NIST design 5 to 100 MHz

[EMAIL PROTECTED] wrote on 09/24/2008 08:44:30 PM: > On Mon, 22 Sep 2008 15:52:19 +1200, [Gerhard] wrote: > [snip] > > >For maximum phase stability the BNC connectors should replaced by > >threaded connectors such as TNC, SMA , N etc. > > The next iteration will have to live with BNC because R

Re: [time-nuts] LPRO 101 ADJUSTMENT

[EMAIL PROTECTED] wrote on 08/02/2008 04:38:14 PM: > [snip] > > It would be nice to find a relatively simple and inexpensive 10MHz > synthesizer that has a resolution of closer to 1E-14 to avoid messing > with the EFC at all. A 48-bit-accumulator DDS chip such as the Analog Devices AD9852

Re: [time-nuts] Anti-Static conductive foam warning

The turning into goo is called "reversion", and is a property of some kinds of polyurethane. There is a good explanation in US patent 4040991, and in www.wolaa.org/files/Spring_2007_OHS_-_WOL_In-house_Expertise.pdf . It can be difficult to find a solvent for the goo. As for corrosion causing u

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