Re: [time-nuts] Spectracom 8182 Netclock/2
I went through something very similar when I reverse-engineered a module Data I/O used in their programmers for disk storage (the MSM, or Mass Storage Module). The best way I've found to do it is make a drawing of the board itself, plus all its IC's and other components. Doesn't have to be anything fancy, just an outline plus little rectangles (suitably labeled, of course) for the components. Next, identify your power and ground rails. Finally, using a continuity tester (preferably something which beeps when it gets shorted), start with a pin on an IC you know is not the IC's Vcc or ground pin, and check for continuity to every other IC and component. Lather, rinse, repeat. As you go, make a "netlist" of which IC pin connected to which component, or power or ground rail. Example: U1-11 (means the IC labeled U1, pin 11): U2-6, U5-2, 10k pullup to +5 This means pin 11 on U1, pin 6 on U2, and pin 2 on U5 would all be connected together, and to a 10k pull-up resistor to the +5V rail. Once you finish doing the entire board, you can sit down at your computer with your favorite schematic-drawing package and your netlist, and re-draw the circuit. Yes, it's time consuming, and takes lots of patience. It took me over a month to do the MSM, and that was a relatively simple board. However, in the end, you have a very usable schematic and a great idea of how the circuit elements interact. This is never a bad thing. Happy tweaking. *** REPLY SEPARATOR *** On 15-Oct-11 at 16:53 Bob Betts wrote: >Hello All: >I have four Netclock/2 systems (model 8182), from Spectracom, which are >being modified for a switching broadcast monitor console. I'm in the >process of reverse engineering the schematic, since service schematics >seem to be totally unavailable. It's a time-consuming process and quite >tedious. When chip numbers are erased, it gets to be even more exciting. >Anyhow, has anyone else ever done any work along this line? Maybe we can >swap and combine info, or possibly someone might have an actual schematic. >These were typically purchased for broadcast studios. > >These are obsolete as far as the company is concerned, but they refuse to >support a customer's investment with just a few sheets of paper (we bought >4 of them). They won't even supply documentation for "new" products. >Maybe I'm too old fashioned, but after 48 years of manufacturing >specialized comms equipment, we'll go way out of our way to support our >dedicated customers ... old and new. What I do know is that I won't do >business with them, again. > >Any help will be gratefully appreciated. >Please let me know any cost involved. > >Thanks in advance, > >Bob > >N1KPR >(ACE - AmComm) > > > > >http://www.bobsamerica.com >* Music * Audio * Radio * >"It's all good" >___ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > >__ Information from ESET NOD32 Antivirus, version of virus >signature database 6546 (20111015) __ > >The message was checked by ESET NOD32 Antivirus. > >http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner & Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m "Quid Malmborg in Plano..." ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Anyone have information on an Anritsu OCXO?
Greetings, I saw an Anritsu OCXO 10MHZ Reference Oscillator, 342U96830, on eBay.I'm hoping a time-nut might have pin outs, operating voltage and/or specifications. The usual search engines didn't provide any clues. Tnx Wayne / WA7NE ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
Mike S wrote: At 05:46 PM 10/15/2011, Jim Palfreyman wrote... http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com,2011://3.83661&fullPageURL=/archives/2011/10/speedy-neutrino.php Comments please! What an annoying website. Here's a better source, without all the unnecessary pagination and pablum. http://arxiv.org/abs/1110.2685 and the original one in a more readable form: http://dvice.com/archives/2011/10/speedy-neutrino.php -- Bob Smither, PhD Circuit Concepts, Inc. = An armed society is a polite society. -- Robert Heinlein = smit...@c-c-i.com http://www.C-C-I.Com 281-331-2744(office) -4616(fax) <>___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
iov...@inwind.it said: > I'm a bit confused. While I may figure what the reference frame of a single > GPS satellite is, I wonder what is the reference frame of any visible > constellation of GPS satellites as a whole? Help please. You can pick any reference frame you want. Often it makes analyzing what is happening a lot simpler if you pick a particular one. You should get the same answer with a different reference frame, it just takes more work. -- These are my opinions, not necessarily my employer's. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
El 16/10/2011 02:14, iov...@inwind.it escribió: And further, what the author states, in other words, would mean that the two clocks at Earth, in the frame in which the measurement was made, were off by 60 ns, isn't it? More or less :) I'm also not sure of the accuracy of the phrase "The clocks in the OPERA experiment are orbiting the earth in GPS satellites", since as far as I've understood the GPS is used to use common view for comparison of the Cs clocks. And it seems that the author does not know that relativity has already been taken into account in the GPS system. I'm of the same opinion as Magnus: I do not think that this paper will bebunk the OPERA one, not even a little :) Regards, Javier, EA1CRB ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
On 10/16/2011 01:59 AM, iov...@inwind.it wrote: From mi...@flatsurface.com, Oct 16,2011, 01.50 At 05:46 PM 10/15/2011, Jim Palfreyman wrote... http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com,2011://3. 83661&fullPageURL=/archives/2011/10/speedy-neutrino.php Comments please! What an annoying website. Here's a better source, without all the unnecessary pagination and pablum. http://arxiv.org/abs/1110.2685 Well, the title of the paper is "Times of Flight between a Source and a Detector observed from a GPS satelite". From a single GPS satellite? Does this make any sense? Therein lies the prime weakness of that paper. It assumes that a single GPS bird was used, while in fact many was being used. It is an expansion of the statement: The Cs4000 oscillator provides the reference frequency to the PolaRx2e receiver, which is able to time-tag its “One Pulse Per Second” output (1PPS) with respect to the individual GPS satellite observations. However, more usefull information follows: The latter are processed offline by using the CGGTTS format [19]. The two systems feature a technology commonly used for high-accuracy time transfer applications [20]. They were calibrated by the Swiss Metrology Institute (METAS) [21] and established a permanent time link between two reference points (tCERN and tLNGS) of the timing chains of CERN and OPERA at the nanosecond level. This time link between CERN and OPERA was independently verified by the German Metrology Institute PTB (Physikalisch-Technische Bundesanstalt) [22] by taking data at CERN and LNGS with a portable time-transfer device [23]. The difference between the time base of the CERN and OPERA PolaRx2e receivers was measured to be (2.3 ± 0.9) ns [22]. This correction was taken into account in the application of the time link. (Both quotes is from page 9 in the OPERA paper) For me, this reads out that they use common view for comparison of the cesium clocks, in which case main part of the time sent from the satelite would in fact cancel, and I also expect even more detailed effects like ionspherics is being canceled, which was not even covered. More details both of the processing actually done would assist, but I assume it will cover many of the relative effects that GPS time involves. However, this paper did not really provided a good insight into that. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
On 10/16/2011 01:50 AM, Mike S wrote: At 05:46 PM 10/15/2011, Jim Palfreyman wrote... http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com,2011://3.83661&fullPageURL=/archives/2011/10/speedy-neutrino.php Comments please! What an annoying website. Here's a better source, without all the unnecessary pagination and pablum. http://arxiv.org/abs/1110.2685 Thanks. While the annoying website was scetchy in the science pub way, and also failed to explain why neutrinos would experiencing this but not photons, the paper is scetchy in that it makes quite rough assumptions on the GPS system as a time transfer mechanism AND fails to address the much tighter time difference of 2.4 ns that the time-transfer experiment achieved. It is a good comment that you need to consider the reference frame of GPS birds etc. It fails to analyze what is already being done and researched in that field. So no, I do not think this paper debunk the OPERA paper, at least not by itself. I'm to tired to make a detailed break-down right now, therefore my schetchy comments. I can dig up papers and provide detailed accounts if needed. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
>Well, the title of the paper is "Times of Flight between a Source and a >Detector observed from a GPS satelite". From a single GPS satellite? Does this >make any sense? >Antonio I8IOV And further, what the author states, in other words, would mean that the two clocks at Earth, in the frame in which the measurement was made, were off by 60 ns, isn't it? Antonio I8IOV ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
>From mi...@flatsurface.com, Oct 16,2011, 01.50 > >At 05:46 PM 10/15/2011, Jim Palfreyman wrote... >>http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com,2011://3. 83661&fullPageURL=/archives/2011/10/speedy-neutrino.php >> >>Comments please! > >What an annoying website. > >Here's a better source, without all the unnecessary pagination and >pablum. http://arxiv.org/abs/1110.2685 Well, the title of the paper is "Times of Flight between a Source and a Detector observed from a GPS satelite". From a single GPS satellite? Does this make any sense? Antonio I8IOV ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Spectracom 8182 Netclock/2
Hello All: I have four Netclock/2 systems (model 8182), from Spectracom, which are being modified for a switching broadcast monitor console. I'm in the process of reverse engineering the schematic, since service schematics seem to be totally unavailable. It's a time-consuming process and quite tedious. When chip numbers are erased, it gets to be even more exciting. Anyhow, has anyone else ever done any work along this line? Maybe we can swap and combine info, or possibly someone might have an actual schematic. These were typically purchased for broadcast studios. These are obsolete as far as the company is concerned, but they refuse to support a customer's investment with just a few sheets of paper (we bought 4 of them). They won't even supply documentation for "new" products. Maybe I'm too old fashioned, but after 48 years of manufacturing specialized comms equipment, we'll go way out of our way to support our dedicated customers ... old and new. What I do know is that I won't do business with them, again. Any help will be gratefully appreciated. Please let me know any cost involved. Thanks in advance, Bob N1KPR (ACE - AmComm) http://www.bobsamerica.com * Music * Audio * Radio * "It's all good" ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
At 05:46 PM 10/15/2011, Jim Palfreyman wrote... http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com,2011://3.83661&fullPageURL=/archives/2011/10/speedy-neutrino.php Comments please! What an annoying website. Here's a better source, without all the unnecessary pagination and pablum. http://arxiv.org/abs/1110.2685 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
>From jim77...@gmail.com, Oct 15, 2011, 23.46 >http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com,2011://3. 83661&fullPageURL=/archives/2011/10/speedy-neutrino.php > >Comments please! I'm a bit confused. While I may figure what the reference frame of a single GPS satellite is, I wonder what is the reference frame of any visible constellation of GPS satellites as a whole? Help please. Antonio I8IOV ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Speedy neutrino puzzle solved
Now if tvb had loaded up his van with caesium clocks and driven back and forth between the two stations several times, then corrected for altitude/gravity effects, would he not have revealed the timing problem? cheers, Neville Michie On 16/10/2011, at 8:46 AM, Jim Palfreyman wrote: http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com, 2011://3.83661&fullPageURL=/archives/2011/10/speedy-neutrino.php Comments please! ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Speedy neutrino puzzle solved
http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com,2011://3.83661&fullPageURL=/archives/2011/10/speedy-neutrino.php Comments please! ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Cambrideg Thermionics & Freq Measurements...
Hello The Net: The frequency measurement division broke off, but was still in Cambridge in ~2007. I got a call from them about a 19 KHz pilot tone generator that was off freq at a FM/NCE station on Cape Cod. After replacing the Optimod ($100) xtal, all was fine. I will eventually think of that organizations name, but for now the POC was Richard. Yes, his techniques were cryptic, but I doubt if his techniques exceeded the capability of any time or freq nut's capability. I would start with a search at SBE for such freq measurement organizations. Stan, W1LE Cape CodFN41sr On 10/15/2011 10:57 AM, J. Forster wrote: Cambridge Thermionic was on Concord Ave, just east of the Fresh Pond circle. The building is now a storage warehouse. They were mostly making screw-machine components by the early 60s. They had a vast array of stake-in terminals and similar stuff. Very good product, IMO. You could get damn near anything you could imagine in terminals from them, uninsulated and insulated. They also made a bunch of other electronic hardware like coil forms. Again, very good quality. The other thing they made was thermoelectric heat pumps and products using them, like small "ice bath" references for thermocouples. I suspect this was related to their expertise with ceramic-metal attachment. At some point (70s? 80s? 90s?) they moved someplace else and changed their name to Cambion. Best, -John Les, I do sort of remember Cambridge Thermionics. I came across their name back in the late 60's or early 70's when I first got in the frequency measurement "business". I think I also remember seeing their name as a parts supplier in some WW-2 military radio manuals. Burt From: "Lester Veenstra" Bert: I wonder if you happen to remember a company called Cambridge Thermionics. Located in Cambridge MA, they made ceramic slug tuned coil s but in one corner was an individual with the off air frequency measuring service. As a duty engineer up the read at WCOP in Lexington, I frequently would get calls from him to tick a dummy plug in the modulator input patch (turning the board gain down was too much residual noise), so he could measure us, and more often, to remove the carrier for a few seconds so you could measure some one co-channel. He never wanted to talk about how it did it, and absolute would not accept visitors who might learn his dark trade secrets. I had assumed that these days a GPSDO would remove the need for the monthly "freq service" but I guess not. I stood my last midwatch at COP and reported to the Boston Army station for induction into the USN the next morning. 73 Les Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Cambrideg Thermionics & Freq Measurements...
Cambridge Thermionic was on Concord Ave, just east of the Fresh Pond circle. The building is now a storage warehouse. They were mostly making screw-machine components by the early 60s. They had a vast array of stake-in terminals and similar stuff. Very good product, IMO. You could get damn near anything you could imagine in terminals from them, uninsulated and insulated. They also made a bunch of other electronic hardware like coil forms. Again, very good quality. The other thing they made was thermoelectric heat pumps and products using them, like small "ice bath" references for thermocouples. I suspect this was related to their expertise with ceramic-metal attachment. At some point (70s? 80s? 90s?) they moved someplace else and changed their name to Cambion. Best, -John > Les, > > I do sort of remember Cambridge Thermionics. I came across their > name back in the late 60's or early 70's when I first got in the > frequency measurement "business". I think I also remember seeing > their name as a parts supplier in some WW-2 military radio manuals. > > Burt > >>From: "Lester Veenstra" >> >>Bert: >> I wonder if you happen to remember a company called Cambridge >>Thermionics. Located in Cambridge MA, they made ceramic slug tuned coil >> s >>but in one corner was an individual with the off air frequency measuring >>service. As a duty engineer up the read at WCOP in Lexington, I >> frequently >>would get calls from him to tick a dummy plug in the modulator input >> patch >>(turning the board gain down was too much residual noise), so he could >>measure us, and more often, to remove the carrier for a few seconds so >> you >>could measure some one co-channel. He never wanted to talk about how it >> did >>it, and absolute would not accept visitors who might learn his dark trade >>secrets. >> >> I had assumed that these days a GPSDO would remove the need for the >>monthly "freq service" but I guess not. >> >>I stood my last midwatch at COP and reported to the Boston Army station >> for >>induction into the USN the next morning. >> >>73 Les > > Burt I. Weiner Associates > Broadcast Technical Services > Glendale, California U.S.A. > b...@att.net > www.biwa.cc > K6OQK > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] need example frequency vs temp equation
On Oct 15, 2011, at 7:50, Ivan Cousins wrote: > Hi Jim, > When you mentioned > "I found a thesis from someone who was modeling this kind of thing (actually > he was developing an set of tools to design it) and I can probably crib his > matlab code.". > > I was interested so I did a Google scholar search to find that reference. > > I found. > "Design Technique for Analog Temperature Compensation of Crystal Oscillators" > http://scholar.lib.vt.edu/theses/available/etd-11262001-111453/unrestricted/etd.pdf Exactly... When I get my little models done, I'll be sure to let all the nuts know. Jim ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] need example frequency vs temp equation
Hi Jim, When you mentioned "I found a thesis from someone who was modeling this kind of thing (actually he was developing an set of tools to design it) and I can probably crib his matlab code.". I was interested so I did a Google scholar search to find that reference. I think I found the reference you referred to. keywords used "thesis temperature compensated oscillator model tool" http://scholar.google.com/ unclick patents Look on the right for the available pdf files. I found. "Design Technique for Analog Temperature Compensation of Crystal Oscillators" http://scholar.lib.vt.edu/theses/available/etd-11262001-111453/unrestricted/etd.pdf Another interesting reference paper found in that search was: "Performance analysis and architectures for INS-aided GPS tracking loops" http://waas.stanford.edu/~wwu/papers/gps/PDF/AlbanIONNTM03.pdf This has a clear explanation of architectures used in GPS tracking loops. Thanks John Cousins On 11:59 AM, Jim Lux wrote: On 10/12/11 10:10 PM, Bernd Neubig wrote: Hi Jim, There are different types of TCXO compensation techniques on the market. Each of them generating a different style of f(T) characterisitcs. Furthermore the f(T) response varies from unit to unit, because each TCXO is usually uindividually compensated (or sometimes in groups of similar quartz f(T) characteristics. To name a few compensation types: The classical types can be broken down in direct and indirect compensation: 1. the first one using a thermistor/capacitor/resistor network connected in series to the quartz crystal resonator. This network represents a temprature dependenta load caopacitants to the crystal. 2. the indirect ones using a thermistor/resistor network which generates a temperature-dependent DC voltage, which is fed to a varactor diode (in series to the crystal) and thus changing f over T. Sometimes the passive network is combined with an op-amp to realize a higher voltage swing. 3. The modern TCXO (all these small ceramic packaged SMD units) use IC-based compensation techniques. There are different TCO on the market which differ in their working principle slightly. But in general, most of those IC's contain a temperature sensor, from which a DC voltage represented by polynomial of 3rd or higher order is generated by analog techniqes: The coefficients for the polynomial are - a0 = reference voltage - a1 = outoput from temperature sensor - a2 = output from temperature sensor multiplied by the same with an analogue multiplier - a3 = output of a2 multiplied with temp sensor output etc. These components are fed into an analogue summing amplifier through analogue potentiometers, which are setting the magnitude of each coefficient. This summed-up voltage ploynomial feeds one or two varactor diodes in series to the crystal. In the (still individual, but highly automated)compensation process, the coefficient potentiometers are set set through a serial data line such, that the f(T) characteristic shows minimum deviation over temperature. This process runs through the whole operating temperture range in small temperature steps, mostly in both directíons to take into account some of the hysteresis of the crystal's f(T) characteristic. 4. Besides these techniques there are some other approaches, such like the first generation of digitally compensated TCXO, which were using loo-up tables for eacht temperature increment (bit), which contains the digital word for the necessary compensation voltage. The disadvantage of this method are the discontinuities between eacht temperature bit, causing small frequency jumps and/or jitter To conclude: Because of the individual process, TCXO do not show any uniform f(T) characteristic. You can fit it by a higher order polynomial, but the responses are looking different for each individual unit. Best regards Bernd, DK1AG AXTAL GmbH& Co. KG www.axtal.com Thanks a lot.. This was quite informative. I think all I need for this purpose (it's an example of what you might have to deal with) is any old scheme. Given the hidebound reactionary conservatism of spaceflight electronics designers and their even more conservative review board members, the first one (temperature dependent resistor and capacitor, or maybe varactor) is probably the most plausible. And for the non-temperature compensated case (e.g. the CPU clock), the standard AT cut cubic will probably work just fine. I found a thesis from someone who was modeling this kind of thing (actually he was developing an set of tools to design it) and I can probably crib his matlab code. (which is all I really need...) I'm trying to come up with some illustrative experimental scenarios where you have multiple widgets varying in temperature (orbiting around something, so they cycle every 90-100 minutes, with a bigger cycle on a monthly/annual basis), and you want to do comparisons/ensembles/doppler measurements. So it's not that it has to exactly match
