[time-nuts] Serial port / Mouse issue (was mentioned inThunderbolt Monitor)
Besides the previous mentioned Time-Nuts reference in this thread to the so-called psychomouse problem on November 1, 2010 there was a thread on November 29, 2011 entitled Unplug T-bolt before booting up...?? that had most of the information covered here. Although this problem has been known for years I still haven't made the change to the laptop I use for testing Thunderbolts and have gotten used to the occasional surprise of watching the mouse cursor dart all over the screen. ;-) -Arthur ___ 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] Trimble TB PCB board gpsdo question
Hi, anybody has the Trimble Thunderbolt GPSDO but in a letter size PCB board from the Hong-Kong epay seller It has a SMC socket and beside the normal 10 MHz output it has a second frequency output 9,830400 MHz. What is the purpose for this freq in the GSM base station... Please contact me offline to exchange some experience, data. Many thanks and best regards Ernie. ___ 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] Trimble TB PCB board gpsdo question
On 1/25/2013 9:00 AM, Erno Peres wrote: it has a second frequency output 9,830400 MHz. What is the purpose for this freq in the GSM base station... None that I can think of. But it is 8 times the CDMA chip rate of 1.2288 MHz, so would be useful in a CDMA base station. ___ 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] Trimble TB PCB board gpsdo question
Hi Mike, Thanks a lot for the info, Rgds Ernie -Original Message- From: Mike S mi...@flatsurface.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Fri, Jan 25, 2013 3:11 pm Subject: Re: [time-nuts] Trimble TB PCB board gpsdo question On 1/25/2013 9:00 AM, Erno Peres wrote: it has a second frequency output 9,830400 MHz. What is the purpose for this freq in the GSM base station... None that I can think of. But it is 8 times the CDMA chip rate of 1.2288 Hz, so would be useful in a CDMA base station. ___ ime-nuts mailing list -- time-nuts@febo.com o unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts nd 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] Serial port / Mouse issue (was mentioned inThunderbolt Monitor)
Panasonic has a registry hive to fix the psychomouse issue on toughbooks with integrated gps use the Panasonic.ca site much better organized than the us site Sent from my iPhone On Jan 25, 2013, at 7:12 AM, Arthur Dent golgarfrinc...@yahoo.com wrote: Besides the previous mentioned Time-Nuts reference in this thread to the so-called psychomouse problem on November 1, 2010 there was a thread on November 29, 2011 entitled Unplug T-bolt before booting up...?? that had most of the information covered here. Although this problem has been known for years I still haven't made the change to the laptop I use for testing Thunderbolts and have gotten used to the occasional surprise of watching the mouse cursor dart all over the screen. ;-) -Arthur ___ 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] One Kg Quartz Resonator
On 01/24/2013 07:12 PM, Bob Camp wrote: Hi If you take the position that a primary standard is only functional if it's under the ideal nominal conditions - you have no primary standards at all. They all require corrections of one sort or the other. Having a system with no standards is not a system at all... The practical approach is to define the ideal conditions in a way that you can indeed correct back to them. The most common way is to take the contribution to zero. There obviously are other approaches. Regardless of weather you take it to zero or x.xxx the net result is the same, as long as everybody does the same thing. There is no real standard of anything holding up to the ideal primary standard that some people think of. Rather, one way or another there are practical physical limits which comes into play. Defining an ideal case is needed such that corrections can be made when it is not ideal. The 0 K ideal situation is in fact non-reachable by todays knowledge, but we can correct for the black body temperature shift. Work on the replacement of the NIST F1 will use a cooled tube to lower the black body temperature, and that significantly reduces the shifts and instabilities. One has to recall that the selection of Caesium was done with what was believed as the best combination of repeatability and least dependence of magnetic fields. The magnetic field dependence was in fact better for Thallium which also has higher frequency. However, it was believed that the higher frequency would cause difficulty in repeatability even if it's properties was know better. With todays knowledge we know that the C-field can be servo-steered, by looking at the side-lobes, this removes much of the C-field sensitivity issue, even if it still makes sense. Much work has gone into removing or compensating many of the effects. As we look forward, it might be that rubidium is the next solution, as there is benefits in laser-cooling and atom-to-atom interactions in the balls of the fountain. Things is indeed moving forward, and modern ion traps as well as optical clocks far outshines the capabilities of fountains. So what's a primary standard, but what we currently think is the best technical solution for a reference that has repeatability and stability compared to other technical solutions. Look at how the meter definition has changed over time, and how it now has been replaced by being tied to be a derived property of the SI second. While the avrogado ball might be a significantly better solution than the lump of metal we have now, I think there is difficulties in the repeatability which makes the Watts balance a much more attractive solution. Then again, maybe there is a benefit in the quartz resonator solution, who knows. Oh, by the way... the SI second as such does not depend on the geoid, since if you place to standards at the same acceleration they will concurr, within their design limits. However, for the use of dispersed standards contributing to the TAI time-scale, the geoid kicks in, as can be found in the SI brochure, 8th edition. I knew I saw it there, but now I looked it up. 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.
[time-nuts] Hp58540a
Hello out there!! Just got a misbehavin' Symmetricon 58450A unit, came with error, which I knew. Silly me. Error seems to be 118, but of course i could not find anything beyond two versions of the user manual. This one came with 2400 baud, and, ok, the seller wasn't too clear, 'cause it has the infamous 1 pulse per 2 sec, as noted before on the list. Ok, I said, I've established communications, let;s see if I can rectify the error by the command :SYSTem:PRESet Hoo Boy. Shoulda followed the advice below in my signature. It's sending a T followed by 22 address (?) hex values, then crlf one after another, in order. Cycling power won't stop it, sending commands won't stop it, yikes. Is it a Mayan Calendar? Will the world come to an end when or if it ever stops? Anyone have any ideas or a source I could not find in either the archives or online for tech info? The oven works, btw, I watched it warm up and change frequency when I powered up...so oscillator and output sections are working at least. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. De Erroribus Medicorum, R. Bacon, 13th century. If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com ___ 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] Better gps antennas than a Symmetricom 58532A
On 01/24/2013 03:52 PM, John Lofgren wrote: Should I make it a habbit of TDRing my GPS antennas, receivers and splitters? Cheers, Magnus I think that question ties into some of the other responses to the original post. The value of doing the TDR measurement would probably depend on your cable lengths and how likely you think it is that a connector mismatch would cause cable reflections that might smear the GPS signals. Since you're fortunate enough to have a TDR, it might be interesting to do it just to see how much mismatch there really is. If the resolution of the measurement is good enough you should be able to see all of the connectors. If nothing else, it might tell you if you have a bad cable end or a loose connection. Electrical TDRs excel on short distances, as they have great time resolution, but the dynamics isn't great. VNAs has great dynamics, but tend to lack the time resolution. The high frequency losses of cabling does however make some of the details go lost anyway, and it also kicks in for reflections. Sufficiently lossy cables makes impedance mismatches less critical as the reflection at the sink side would need to traverse the cable twice, as well as being reflected at the source side. So low-loss cables also calls for lower reflections (rather than impedance matching really) in order to achieve the higher system performance. TDRing may not be the ultimate tool, but it is highly educative at least. :) Maybe the Italian guys should have run an optical TDR on their timing setup before doing the neutrino measurements :) Actually, that would have meant that they where suspecting things from start. Also, validating connections means unhooking them, allowing for human errors on each location. 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.
[time-nuts] FTS oscillator sale
Hi, I put up an FTS 1000A/100 oscillator on the eBay. Stability day in the PIX. Corby ___ 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] Better gps antennas than a Symmetricom 58532A
Hi The other nice thing about TDR's is that the units come out in units of time. If you are working on a timing system, there's much less opportunity to goof things up by a conversion error. Bob On Jan 25, 2013, at 6:37 PM, Magnus Danielson mag...@rubidium.dyndns.org wrote: On 01/24/2013 03:52 PM, John Lofgren wrote: Should I make it a habbit of TDRing my GPS antennas, receivers and splitters? Cheers, Magnus I think that question ties into some of the other responses to the original post. The value of doing the TDR measurement would probably depend on your cable lengths and how likely you think it is that a connector mismatch would cause cable reflections that might smear the GPS signals. Since you're fortunate enough to have a TDR, it might be interesting to do it just to see how much mismatch there really is. If the resolution of the measurement is good enough you should be able to see all of the connectors. If nothing else, it might tell you if you have a bad cable end or a loose connection. Electrical TDRs excel on short distances, as they have great time resolution, but the dynamics isn't great. VNAs has great dynamics, but tend to lack the time resolution. The high frequency losses of cabling does however make some of the details go lost anyway, and it also kicks in for reflections. Sufficiently lossy cables makes impedance mismatches less critical as the reflection at the sink side would need to traverse the cable twice, as well as being reflected at the source side. So low-loss cables also calls for lower reflections (rather than impedance matching really) in order to achieve the higher system performance. TDRing may not be the ultimate tool, but it is highly educative at least. :) Maybe the Italian guys should have run an optical TDR on their timing setup before doing the neutrino measurements :) Actually, that would have meant that they where suspecting things from start. Also, validating connections means unhooking them, allowing for human errors on each location. 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. ___ 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] FTS oscillator sale
Instead of making us dig for it, could you provide an item number? -Bob On Fri, Jan 25, 2013 at 4:41 PM, cdel...@juno.com wrote: Hi, I put up an FTS 1000A/100 oscillator on the eBay. Stability day in the PIX. Corby ___ 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] Hp58540a
Well, heck, never mind! Finally rtfm, and found out how to shut off time reporting. Back to real troubleshooting to find cause of red led... sorry to stir the hive up for no reason (yet!) red face and flat forehead. Don -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. De Erroribus Medicorum, R. Bacon, 13th century. If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com ___ 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] FTS Oscillator Sale
Sorry here it is! Item number: 321062141056 Corby ___ 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.
