Re: [time-nuts] Timing on Ethernet

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Magnus Danielson wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] RETRY > > From: "Bill Hawkins" <[EMAIL PROTECTED]> > Subject: Re: [time-nuts] Timing on Ethernet > Date: Sun, 5 Aug 2007 16:25:36 -0500

Re: [time-nuts] Timing on Ethernet

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Thomas A. Frank wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] RETRY > > Ah, but what if one used the tunnel itself as a waveguide, and > propagated an RF signal down it? Would it then reliably arri

Re: [time-nuts] Timing on Ethernet

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Neville Michie wrote: > Hi, > Low frequencies penetrate the ground to some depth. > However, propagation may vary seasonally as groundwater > concentrations change. > cheers, Neville michie > Neville Even without the sea

Re: [time-nuts] Timing on Ethernet

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Neville Michie wrote: > Thinking outside the square > What you need is a low frequency transmitter exactly in the middle of > the ring... > > Neville Michie > Neville Isn't the accelerator located underground? Bruce

Re: [time-nuts] Timing on Ethernet

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Pablo Alvarez Sanchez wrote: > Dear timing colleges, > > At CERN we are considering the possibility of using Ethernet as a real > time field bus. > We may use IEEE 1588 to distribute precise UTC and Ethernet Powerlink or > a s

Re: [time-nuts] Software Sawtooth correction prerequisites?

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Henk ten Pierick wrote: >> However if one adopts a non linear control theory approach, one can >> actually design high order modulators that both stable in theory >> and in >> practice. >> > > Unconditionally? Do you have

Re: [time-nuts] Software Sawtooth correction prerequisites?

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Henk ten Pierick wrote: > On Jul 24, 2007, at 1:32, Dr Bruce Griffiths wrote: > > >> Perhaps a software implementation of a 1 bit oversampled DAC the 1 bit >> output of which is low pass filtered to con

Re: [time-nuts] Building a DC Block Thingy....

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Jason Rabel wrote: > I have a NTS-200 on the way, but one thing about them is their GPS power > output is 12V instead of the usual 5V. I really didn't want to modify the > board any in an irreversible fashion so I was hoping to build

Re: [time-nuts] Why Cesium and Rubidium only

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Bob Paddock wrote: > On Friday 27 July 2007 04:14, Dr Bruce Griffiths wrote: > > >> 22GHz, >> (15GHz) >> (~40.5 GHz) than either the caesium >> (9.192GHz) or rubidium >> (6.8GHz) >>

Re: [time-nuts] Why Cesium and Rubidium only

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Don Collie wrote: > Please excuse my ignorance [I marvel/wonder at some of the essotevric > comments on this group], but why are atomic clocks reliant on these two rare > elements? - why not mercury, or water vapor, they are a lot e

Re: [time-nuts] Software Sawtooth correction prerequisites?

Tom Van Baak wrote: >> This sure sounds like a more complicated measurement than is necessary >> to me. If you have a 10 MHz oscillator, simply feed it into the "D" >> input into a latch clocked by the de-sawtoothed GPS 1PPS. The output of >> the latch is a 0 or 1 depending on the precise phase of

Re: [time-nuts] HP 5370B low frequency modulation

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Brooke Clarke wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] > > Hi Didier: > > Would you elaborate on the comment "Gold plated connectors are a well known > example." Do you mean when soldered with Lead

Re: [time-nuts] HP 5370B low frequency modulation

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Mike Feher wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] > > I believe it is almost impossible to have an intermittent thermal fuse due > to their very clever design. Although over age they can open up. On

Re: [time-nuts] HP 5370B low frequency modulation

Hej Magnus Since the 10811 oven heater supply in a 5370 is unregulated one possible cause is a quasi periodic variation of the mains supply voltage. Bruce ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-

Re: [time-nuts] HP 5370B low frequency modulation

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Hej Magnus Could there perhaps be an intermittent thermal fuse in the 10811? Bruce ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mail

Re: [time-nuts] HP 5370B low frequency modulation

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Magnus Danielson wrote: > Hej Bruce, > > >> Oscillation/cycling of oven temperature? >> Oven controller oscillation? >> > > Might be, but then my "loadingcondition" has caused the oven control out of > stability. This would ce

Re: [time-nuts] 5 MHz from 10 MHz

Dick, W1KSZ wrote: > I have several 10 MHz sources that are locked to GPS. I just > acquired an HP 8640B that requires a 5 MHz reference input. > Other than building up something, are their any commercial > devices that will give me a 5 MHz output from a 10 MHz source ? > > Thanks, > Dick Wenze

Re: [time-nuts] HP 5370B low frequency modulation

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Magnus Danielson wrote: > Hi fellow time-nuts, > > As I was going to make a casual measurement of the HP 5370B 10 MHz output, > i.e. > that of its HP 10811-60111 OCXO, I came to see an unexpected modulation. It > has > a slow modula

Re: [time-nuts] Oncore VP problem

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] M. Warner Losh wrote: > In message: <[EMAIL PROTECTED]> > Dr Bruce Griffiths <[EMAIL PROTECTED]> writes: > : If one booted a FreeBSD machine with an active GPS timing receiver > : connected to a

Re: [time-nuts] Oncore VP problem

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: > > > Thanks Bruce > > I've got it sorted now, for the time being at least:-) > > I'd love to use a "better" OS, have tried a few flavours of Linux for > example after spending a l

Re: [time-nuts] Metastability in a 100 MHz TIC

Tom Van Baak wrote: The simpler and cheaper D flipflop precedence detector used together with hardware sawtooth correction has far higher resolution. It also has the advantage of not requiring any high frequency clocks. Bruce Since Rick & Dr TAC brought it up some months ago, does anyo

Re: [time-nuts] Metastability in a 100 MHz TIC

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Alan Melia wrote: > Bruce I find this an interesting thread...one maybe naive thought.. > "it would be nice to have a"too-good" stability on the 100MHz TIC but > detracts from the averaging" (My interpretation), this almost su

Re: [time-nuts] Sawtooth correction with a slower TIC

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Richard H McCorkle wrote: > Gentlemen, > I would like to pose a theory question and see if my thinking is > faulty. My original design used a 50 MHz TIC clock and the TMR0 > prescaler as the phase counter giving 20ns single sample res

Re: [time-nuts] Metastability in a 100 MHz TIC

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Tom Tom Van Baak wrote: > Bruce, > > I like your point about the random quantization error in the > sawtooth. Yes, that would help the noise by a few dB. > > On the other hand it would also seem the 10 ns resolution > of the TIC is th

Re: [time-nuts] Metastability in a 100 MHz TIC

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Tom Van Baak wrote: > Richard, > > A 1.6 us window mean you have almost no issues with > the accuracy or stability of your 100 MHz sample clock. > 10 ns out of 1.6 us is 1/2 percent; clock counts won't > exceed 160; a quartz timebase

Re: [time-nuts] Metastability in a 100 MHz TIC

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Ulrich Bangert wrote: > Richard, > > metastability is an effect that happens when the setup times of an > d-flipflop are not met. This can happen (with a certain statistical > likelyhood) when the sources of the data input and the clo

Re: [time-nuts] Metastability in a 100 MHz TIC

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Richard H McCorkle wrote: >With the discussions here on metastable states in TIC > counters, I am asking the experts on the list for their > opinion if the performance of this design would improve > by adding a shift register syn

Re: [time-nuts] Oncore VP problem

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] > > > In a message dated 19/07/2007 02:44:42 GMT Daylight Time, [EMAIL PROTECTED] > writes: > > My suggestion is that you pick up a free

Re: [time-nuts] HP5532A for free

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: > In a message dated 7/17/2007 19:12:15 Pacific Daylight Time, > [EMAIL PROTECTED] writes: > > >> My old HP 523C does not have Nixie-tubes, such modern shit. No, it uses >> > pure > >> neon lam

Re: [time-nuts] Cs stability

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Tom Van Baak wrote: >> I guess that is why some GPS antenna cables is temperature-stabilized as well >> as the cement-pidestal for the GPS antenna as it stands on solid rock. The >> same >> place have controlled environment for the c

Re: [time-nuts] Cs stability

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Tom Van Baak wrote: >> Yes it can make sense. >> Place one Cs clock in a chamber where the ambient temperature can be >> adjusted to various fixed temperatures. Compare the phase of its >> 5/10MHz and/or PPS outputs with respect to

Re: [time-nuts] Cs stability

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Tom Van Baak wrote: > The given specs are conservative (in typical HP style) but > I would guess the best ADEV numbers are only for laboratory > conditions. Someone from Agilent/Symmetricom might want > to comment on this. > > >> I

Re: [time-nuts] Cs stability

Pablo Alvarez Sanchez wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] > > Hi, > > I am curious about the total stability of Cs clocks. Normally producers give > you an initial accuracy after 30 minutes of power on and a table with the > Allan deviation for different me

Re: [time-nuts] HP 5370B jitter

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Hej Magnus Magnus Danielson wrote: > Further investigations have now shown that the 10811 output is clean, just a > little 3rd harmonic but nothing to worry about. The INT test point is also > clean. I suspect the output drive part, a

Re: [time-nuts] NIST frequency doubler

Said Attached circuit (which still requires some optimisation) will perform better than the previous Bipolar transistor common base frequency doubler. Bruce CBBJTDoubler.pdf Description: Adobe PDF document ___ time-nuts mailing list -- time-nuts@fe

Re: [time-nuts] NIST frequency doubler

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] > > > In a message dated 7/9/2007 18:34:30 Pacific Daylight Time, > [EMAIL PROTECTED] writes: > > >> Since JFETS have a relatively lar

Re: [time-nuts] NIST frequency doubler

[EMAIL PROTECTED] wrote Thanks for the info Bruce, Magnus, I will be reading the Felton paper to get more info. With a bit of trickery, I bet this circuit can be used with Bipolar transistors. bye, Said Said You mean like the circuit in the attached file? Input transformer configu

Re: [time-nuts] NIST frequency doubler

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Said To give some idea of the transformer ratios required a simulation using pSpice shows that: When using 2 x 2N4393's connected in parallel (limited choice of JFETs available) for each JFET in the NIST circuit, an input transfor

Re: [time-nuts] NIST frequency doubler

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: > Hi Bruce, > > > nice circuit. Many questions: > > I wonder how well it works to get a 5MHz source up to 10MHz? > > Also, would you have recommendations on the transformer part numbers? > (MiniCir

Re: [time-nuts] NIST frequency doubler

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Peter Vince wrote: > Hi Bruce, > > With a quick search of the NIST site, I couldn't find any > mention of this, and the circuit diagram in your GIF was a little > small and fuzzy: is that a crystal on the centre-tap of the sec

Re: [time-nuts] NIST frequency doubler

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Mike Feher wrote: > Well, I guess that is according to NIST. I do not see how an active doubler > can have lower noise than a passive one, especially when the original signal > has already been degraded by 20log2, or 6 dB so the contr

Re: [time-nuts] NIST frequency doubler

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Mike Feher wrote: > Interesting. Diode doublers of this configuration have been around for about > 40 years, and of course so have their FET counterparts. While I never did an > investigation on any additive residual noise, since typi

[time-nuts] NIST frequency doubler

The schematic for a NIST developed, low phase noise frequency doubler is attached. This device appears to perform significantly better than the Wenzel FET doubler specifications at least in the flicker noise region. With suitable modifications to allow individual adjustement/selection of the bia

Re: [time-nuts] May I ask for your advice on a faulty 5370B?

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] S McNamara wrote: > Thanks Bruce, > I used a HP5335A counter to measure the ref out at 10.000,000,3MHz and the > 200MHz test point-1 > on the multiplier board as 200.000,007 MHz > The HP5335 is not calibrated but it looks like the mu

Re: [time-nuts] May I ask for your advice on a faulty 5370B?

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] S McNamara wrote: > G'Day All, > I just purchased a 2nd hand HP5370B counter. > It was last calibrated in 2002 but fails the operators checks. > I have run tests 1-21 and only a few fail. > In step 13 the display indicates 90.9*ns > I

Re: [time-nuts] Troubleshooting SR DG435 Four Channel Digital Delay/Pulse Gen

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Brooke Clarke wrote: > Hi Bruce: > > The common pin has a 100 ns period wave at + and - 500 mv. > One of the center pins on the INT/EX switch had + and - 1 volt at 100 ns > period. > Have Fun, > > Brooke Clarke > http://www.PRC68.com

Re: [time-nuts] Troubleshooting SR DG435 Four Channel Digital Delay/Pulse Gen

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Brooke Clarke wrote: > Hi: > > The DG535 Four Channel Digital Delay/Pulse Generator shows > Ext Clk Error on power up. > The obvious thing to do is turn the rear panel switch to INT, but after > powering up with the switch in either

Re: [time-nuts] ? phase comparison or other device

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Bob Paddock wrote: > "The AD8036 and AD8037, from Analog Devices, are wide bandwidth, low > distortion clamping amplifiers. > The AD8036 is unity gain stable. The AD8037 is stable at a gain of two or > greater. > These devices all

Re: [time-nuts] ? phase comparison or other device

Bob Paddock wrote: >> These devices are a little noisy below 100Hz. >> > > Rather than constantly battle the "there is to much noise", what are > your thoughts on deliberately injecting out-of-band noise? > > As an example: > http://www.analog.com/UploadedFiles/Application_Notes/319765654AN-41

Re: [time-nuts] ? phase comparison or other device

Bob Paddock wrote: > On Saturday 30 June 2007 10:15, Dr Bruce Griffiths wrote: > > >> Not true, there's nothing magic about amplifier saturation, any means >> that limits the amplifier output whilst dropping the small signal gain >> to a low value w

Re: [time-nuts] ? phase comparison or other device

For those of you who are unfamiliar with the bipolar transistor feedback limiter the attached schematic depicts it in use with both a noninverting and an inverting amplifier. The output voltage swing before clamping is limited by transistor Vbe breakdown. However this can be oversome by adding a

Re: [time-nuts] ? phase comparison or other device

John Miles wrote: >> The output of an opamp is always referenced to its power supply, >> regardless of the configuration. If the power supply is noisy, >> the output is noisy. >> > > Beyond a few kHz this may be true, but at lower frequencies even a low-grade > opamp has excellent rejection o

Re: [time-nuts] ? phase comparison or other device

Pete Try changing your input stage to the configuration depicted in the attachment. The input amplifier can then be something like an OP27 without affecting performance. The noise spectrum at the first opamp output will actually be reduced to the opamp (and series resistor) input noise at freq

Re: [time-nuts] ? phase comparison or other device

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Chuck Harris wrote: >> What about the power supply noise that appears at the amplifier output >> during saturation? >> Power supply noise is almost always much larger than the opamp input noise. >> A simple resistor + diode clamp in

Re: [time-nuts] ? phase comparison or other device

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Pete wrote: > Magnus, > > This discussion is why I have allowed the ADA4899-1 to saturate in the ZCD > posted earlier. The transition times up & down in the second stage are 350 > to > 400 ns; thus I believe the <50ns overload recove

Re: [time-nuts] ? phase comparison or other device

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Operating an opamp in saturation for extended periods in a precision circuit is a bad idea, as the changes in dissipation of the various devices in the opamp will change the opamp input offset voltage when it comes out of saturatio

Re: [time-nuts] ? phase comparison or other device

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Pete wrote: > ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] > > Magnus, > > This discussion is why I have allowed the ADA4899-1 to saturate in the ZCD > posted earlier. The transition times up & down in the second

Re: [time-nuts] ? phase comparison or other device

); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Magnus Danielson wrote: > Ulrich, > > >> you are right: Both of these articles should be read with Collins's >> perhaps the better (and newer!) one. >> >> There is however one question remaining for me: When I learned >> electroni

Re: [time-nuts] ? phase comparison or other device

A link to reference 6 in the Collins paper on the design of low jitter hard limiters: http://tmo.jpl.nasa.gov/progress_report/42-107/107D.PDF Bruce ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts

Re: [time-nuts] ? phase comparison or other device

Ulrich Bangert wrote: > Enrico, > > you are right: Both of these articles should be read with Collins's > perhaps the better (and newer!) one. > > There is however one question remaining for me: When I learned > electronics it was generally considered bad design to let an amplifier > run into limi

Re: [time-nuts] ? phase comparison or other device

Pete wrote: > Bruce, > > A few final thoughts. > > 1. Thanks for the critical view; it does help. > > 2. Like many time-nuts I have a reasonably good 10MHz source & > sometimes need to check out a newly acquired OXCO to ensure > it can muster 1E9 or 1E10 performance (with 10x headroom). > An SR620

Re: [time-nuts] ? phase comparison or other device

Ulrich Bangert wrote: > Pete, > > 5. Mini-circuits BLP-1.9 low pass filter. > > terminating the mixer if output with an lowpass/bandpass filter and NOT > with an diplexer is not so good an idea. Where does the rf go? > > Best regards > Ulrich Bangert > > Ulrich This depen

Re: [time-nuts] ? phase comparison or other device

WB6BNQ wrote: > Bruce, > > Can you provide a link to the JPL system you reference above ? > > Thank you, > > BillWB6BNQ > > Bill http://ntrs.nasa.gov/index.jsp?method=order&oaiID=19910016462 There is also, or was, a free to d

Re: [time-nuts] ? phase comparison or other device

Pete wrote: > Bruce, > > This idea is NOT intended to rival the JPL results. Instead, > it's intended to be cheap, easy to replicate & allow rather > low cost instruments to be used to compare good sources > to parts in 1E12, quickly. The 1KHz heterodyne frequency > makes life much easier than 1Hz.

Re: [time-nuts] ? phase comparison or other device

Pete wrote: > Here is a scheme that seems to work well for comparing stable frequency > sources in the range of 10 to 100 second measurement intervals. > > Objective - Measure frequency to +/-2E-12 in less than 1 minute. > > Method - Heterodyne DUT output to 1KHz with a master reference source + >

Re: [time-nuts] another Ebay mixup, 5370

[EMAIL PROTECTED] wrote > Hi Didier, > > looking at the 10MHz input schematics, there is probably an opportunity to > make these 5370B units a lot better. Even the 50MHz and 200MHz multiplier > boards could be done a lot better nowadays, say with Crystal based VCXO's. > > I always like oppo

Re: [time-nuts] another Ebay mixup, 5370

[EMAIL PROTECTED] wrote: > Hi Bruce, > > sounds like I can probably do the 200MHz multiplier board adjustment. I > wonder how much improvement that by itself, with the hardware mods will give? > I'm > just afraid to make things worse. > > I used to work with TV's, and it took me years to

Re: [time-nuts] another Ebay mixup, 5370

[EMAIL PROTECTED] wrote > There are so many trimmer caps inside that for sure I am not going to move a > single one of 'em :) > > Then again I get <50ps jitter with 8.2 readings per second using the > external Ref input, so maybe I should be content with that. That's a lot > better than >

Re: [time-nuts] On Setting the Astronomical Time

M. Warner Losh wrote: > In message: <[EMAIL PROTECTED]> > Hal Murray <[EMAIL PROTECTED]> writes: > : > : > Is there some way to get TT to better than a tenth of a second, or is > : > the earth just too sloppy of a time keeper? > : > : My guess... > : > : The earth is sloppy on this

Re: [time-nuts] another Ebay mixup, 5370

> My 5370A currently has the following characteristics: > With the EXT 10MHz connected to the input jitter is 15ps. > With an FTS1200 5MHz input signal jitter is 46ps. > With an external GPS locked 10MHz input signal jitter is 45ps. > > This illustrates the danger in believing the jitter measured

Re: [time-nuts] another Ebay mixup, 5370

Tom Van Baak wrote: >> Measurements taken from 3325B at 1 MHz: >> >> 5370B reference: INT EXT (same 5087A as 3325B uses) >> Square wave, 2v pk:15-20 ps 11-12 ps >> Sine wave, 2v pk: 50-70 ps 30-35 ps >> Square wave, 1v pk:20-25 ps 12-13 ps >> Sine wave, 1v pk

Re: [time-nuts] another Ebay mixup, 5370

Tom Tom Van Baak wrote: >> In the case of the 5370, page 3-12 of the manual is where it came from ("15. >> Press STD DEV and +/- TI switch. Display should read less than 100 ps (this >> reading is the instrument's jitter).") >> > > I'm wondering if it would be more informative to make three

Re: [time-nuts] another Ebay mixup, 5370

John Miles wrote: > Pretty similar results here, taken from the 5370B's rear-panel output while > running on the internal 10811B (attached). Indicated jitter with this setup > is about the same as it was on the ext ref via the 5087A (10-12 ps). > > I've seen this counter return self-test jitter re

Re: [time-nuts] another Ebay mixup, 5370

John Miles wrote: > Pretty similar results here, taken from the 5370B's rear-panel output while > running on the internal 10811B (attached). Indicated jitter with this setup > is about the same as it was on the ext ref via the 5087A (10-12 ps). > > I've seen this counter return self-test jitter re

Re: [time-nuts] another Ebay mixup, 5370

[EMAIL PROTECTED] wrote: > Hi Bruce, > > just found out that the 10MHz output looks very much like the picture in the > 5370B service manual. > > I am not impressed. HP could have done a better job on that output :( Maybe > my unit isn't broken after all, maybe the 200ps RMS jitter is norma

Re: [time-nuts] another Ebay mixup, 5370

[EMAIL PROTECTED] wrote: > Hi Tom, > > this was the recommended setup (by HP) for checking the internal noise. Feed > the 10MHz output back to the input using a short cable, and set the unit for > "COMMON" input, setting 50 Ohm impedance etc. > > In the meantime I did some more tests, and f

Re: [time-nuts] Pendulums and Atomic Clocks and Gravity :probably more than you want to know...

Bill Beam wrote: > Mike, > > I was afraid someone would say 'Riemann tensor' > The problem with the Riemann tensor is that I don't > think that anyone here can write in down in detail > for this problem (let alone solve it). I surely can not. > > I also don't think that anyone here is ready for th

Re: [time-nuts] Sensing pendulum position, speed, or height

Tom Van Baak wrote: > A Measurement of the Period Stability of a Free Pendulum > http://www.leapsecond.com/history/1996-DeMarchi-Pendulum-Stability.pdf > > Clever solution. His optical gap is something like 5 microns. > > /tvb > > An additional issue is the pointing instability of the laser used

Re: [time-nuts] Sensing pendulum position, speed, or height

Tom Tom Van Baak wrote: >> I would also worry about long-term stability of any optical >> emitter and sensor pair. Any decline in light output over >> time might appear in the data as a phase shift which could >> affect amplitude or period stability. Then there's any tempco >> or voltco issues to c

Re: [time-nuts] FW: Pendulums & Atomic Clocks & Gravity

Bill Beam wrote: >>> Assume satellite in circular orbit. (Not really necessary.) >>> Assume test mass's released at rest wrt satellite center of mass. >>> Inner test mass released closer to Earth and outer released farther >>> >> >from Earth. Also assume no air currents, no relativity, no

Re: [time-nuts] PRS-10 findings

Poul-Henning Kamp wrote: > In message <[EMAIL PROTECTED]>, Peter Vince writes: > > >> I have seen something similar with my 53132A. I was checking >> on the delay variation of an amplifier distributing 10 MHz, and >> noticed a regular sinusoidal pattern, about a third of a nanosecond >>

Re: [time-nuts] FW: Pendulums & Atomic Clocks & Gravity

Bill Beam wrote: > It helps if this problem is solved in a proper (Earth based) inertial frame > and to consider the total energy (kinetic plus potential) of the test masses. > But there are no strictly inertial frames based on the Earth. The earth rotates around its axis (neglecting precession

Re: [time-nuts] FW: Pendulums & Atomic Clocks & Gravity

Bill Beam wrote: >>> Not true. >>> Very simple experiments will show occupants of the satellite that they >>> are in a non-inertial reference frame. (Release a few test masses >>> about the cabin and you will observe that they move/accelerate for no >>> apparent reason, unless the satellite

Re: [time-nuts] FW: Pendulums & Atomic Clocks & Gravity

Bill Beam wrote: >>> Not true. >>> Very simple experiments will show occupants of the satellite that they >>> are in a non-inertial reference frame. (Release a few test masses >>> about the cabin and you will observe that they move/accelerate for no >>> apparent reason, unless the satellite is in

Re: [time-nuts] FW: Pendulums & Atomic Clocks & Gravity

Bill Bill Beam wrote: > On Tue, 29 May 2007 16:31:40 +1200, Dr Bruce Griffiths wrote: > > >> Ulrich, Didier >> >> Talking about forces, gravitational fields etc makes no physical sense >> if the observer's reference frame isn't specified. >> For

Re: [time-nuts] HP E1938 oscillator

Poul-Henning Kamp wrote: > In message <[EMAIL PROTECTED]>, Dr Bruce Griffiths writes: > >> Robert Atkinson wrote: >> > > >> The actual "controlled export" items in the new lists were revised >> recently and such crystal osci

Re: [time-nuts] HP E1938 oscillator

Robert Atkinson wrote: > Hi, > I'd have to agree with Said, > FEI got hit with fines for shipping 1000B OCXO's that were diverted to a > proscribed country. Most major countries that are "allies" of the USA > should be OK though. > It's surprising what is controlled, very high speed 'scopes, low >

Re: [time-nuts] FW: Pendulums & Atomic Clocks & Gravity

Neville Michie wrote: >> Hi All, >> > I am still having difficulty getting my head around the gravity point. > Now I accept, in principle, that due to relativity an intense > gravity field will slow a clock. > My problem is visualising where you will find this field. > At the centre of this

Re: [time-nuts] FW: Pendulums & Atomic Clocks & Gravity

Ulrich, Didier Talking about forces, gravitational fields etc makes no physical sense if the observer's reference frame isn't specified. For an observer in/on a satellite orbiting about the Earth with their reference frame fixed with respect to the satellite. There is no gravitational field, wha

Re: [time-nuts] HP E1938 oscillator

[EMAIL PROTECTED] wrote: > > In a message dated 5/27/2007 16:10:46 Pacific Daylight Time, > [EMAIL PROTECTED] writes: > > >> Technical Notes: >> 1. >> A resolution of n bit corresponds to a quantization of 2n levels. >> > > >> Random snippet from Supplement No1 to Part 774. >>

Re: [time-nuts] HP E1938 oscillator

Said Part of the confusion probably stems from such gems as: Technical Notes: 1. A resolution of n bit corresponds to a quantization of 2n levels. Random snippet from Supplement No1 to Part 774. Bruce ___ time-nuts mailing list time-nuts@febo.com htt

Re: [time-nuts] Pendulums & Atomic Clocks & Gravity

Rex wrote: > On Sat, 26 May 2007 19:54:21 -0700, "Tom Van Baak" <[EMAIL PROTECTED]> > wrote: > > >>> Even fused silica is unstable (see attachment). >>> Single crystal materials should be significantly better. >>> Ageing Invar doesn't do much for its dimensional instability. >>> >>> Bruce >>>

Re: [time-nuts] Pendulums & Atomic Clocks & Gravity

Tom Van Baak wrote: >> Even fused silica is unstable (see attachment). >> Single crystal materials should be significantly better. >> Ageing Invar doesn't do much for its dimensional instability. >> >> Bruce >> > > Tom > Nice plot. Thanks Bruce. Where'd you find it? Someday > I want to visi

Re: [time-nuts] Pendulums & Atomic Clocks & Gravity

Tom Van Baak wrote: Depends on what you mean by "real clocks". The best pendulum clocks, made in the early 1900's, solved almost all the normal sources of error and instability. That left gravitational tides as the one of the few remaining sources of "error", down well below the 1 ppm level. I sa

Re: [time-nuts] Pendulums & Atomic Clocks & Gravity

Brooke Clarke wrote: > Hi Mike: > > Back in the 1800s clock makers found ways to temperature compensate the > pendulum such as putting a Mercury thermometer at the bottom, using metals > with > dissimilar expansion coefficients (Harrison used steel and bronze (no zinc > then)) or materials with

Re: [time-nuts] HP E1938 oscillator

Richard (Rick) Karlquist wrote: > Regarding non-USA requestors: I will need to look > into the customs aspect of this. If anyone on the > list can give me a tutorial on this it would be > helpful. These are "gifts" if that matters for > customs purposes. Also, they have essentially zero > marke

Re: [time-nuts] HP E1938 oscillator

Richard (Rick) Karlquist wrote: > AFAIK, there is no "manual" on the E1938 (in the sense of the 10811 manual). > And I should know. > > I am attempting to compile what information I have > and get it archived on line somewhere. Can you > give me a pointer to the stuff on TVB's site so > I make sur

Re: [time-nuts] New Trimble timing products

Didier > I could not figure if the Resolution-T (or Mini-T) provides carrier > phase data. > The resolution_T only has code phase data available for each SV (according to the Resolution-T system designer reference manual). > Didier KO4BB > Bruce __

Re: [time-nuts] New Trimble timing products

Didier Juges wrote: > Dr Bruce Griffiths wrote: > >> Didier Juges wrote: >> >> >>> Sorry, it's not 15nS rms, it's 15nS at 1 sigma. >>> >>> Didier KO4BB >>> >>> >>> >> Didier &

Re: [time-nuts] New Trimble timing products

Didier Juges wrote: > Sorry, it's not 15nS rms, it's 15nS at 1 sigma. > > Didier KO4BB > Didier Surely the standard deviation (1 sigma) and the rms values are identical? Specifying 1 sigma is perhaps intended to signify that the timing error is stochastic. Bruce

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