Hi Well, back in the 1970’s the orders went out for most government labs that they *must* power gear down at night. They had to re-wire so that the OCXO’s did not stay powered on …… Apparently somebody did the math and decided it did matter.
Bob > On Jan 5, 2020, at 8:38 PM, Robert DiRosario <[email protected]> wrote: > > We have four HP distribution amps. Most of the line distribution cards are 1 > and 5 MHz, some 100 KHz and a few 10 MHz. > > As for the power use by the 10811 oscillators when the equipment is turned > off but still plugged in, we are at a government facility with almost 40 > major buildings. Nothing we can do in our three little ex FEMA trailers > could show up on the electric meter, even if we tried. > > The fun part will be at home, where I try to test the different standards, > using the test equipment I have. > > Robert > > > On 01/05/2020 02:09 PM, Bob kb8tq wrote: >> Hi >> >> The simple answer is that a ~ $100 Chinese GPSDO and a ~ $20 MiniCircuits >> power splitter >> (all off of eBay) should be able to drive a couple of counters and a few >> other pieces of gear. >> >> If they are all “power on” when the bench is in use, daisy chain from the >> “important” stuff to >> the less accurate gear is fine. Indeed this adds to the maintenance checks >> while reducing the >> cost of the distribution hardware. ( = no free lunch). >> >> For normal lab use, the GPSDO output will do fine and it will be more >> accurate than normal >> bench gear. There’s also the “cool kid” factor :). The 10 MHz output can be >> provided for members >> to cal their gear against. >> >> One advantage of the GPSDO approach is that the rest of the bench can be >> fully shut down >> when nobody is around. A simple timer could do the job without anybody >> needing to remember >> this or that switch. >> >> The power savings from shutting the bench down fully will easily pay for the >> GPSDO in under >> a year ….. >> >> Bob >> >>> On Jan 5, 2020, at 1:29 PM, Robert DiRosario <[email protected]> wrote: >>> >>> I'm back, sorry for the delayed response. >>> >>> My understands is in the HP 5340A counter (all HP counters?) the 10544 or >>> 10811 always has power, regardless of the power switch, as long as it is >>> plugged in. Everything at our work bench is always plugged in. >>> >>> History >>> We (the radio club) have three HP 5340A counters, two 5345A counters and an >>> HP 106B. We took one of the 5340As and the 106B to the building with the >>> Cs standard in a minivan with a 12V to 120V inverter. The 106B had a good >>> battery pack, but it was still powered with the inverter. The first test >>> was to put 10 MHz from the Cs standard into the counter, and it read >>> 10000000. MHz. We moved on to plan B, we put the output of the OCXO into a >>> counter what was driven by the Cs standard. The error was less then 0.1 >>> Hz. We made a little change to the 10811 and moved on to the 106. The >>> error on the 5 MHz output was again less than 0.1 Hz, we made a small >>> change to it. We ate our lunch and moved the counter cable back and forth >>> between the 5340A and 106B and watched them. They both stabilized. 20 >>> years latter, I don't recall what the final error was. It was much better >>> than any piece of ham gear anyone would have. >>> >>> In 2011 the club got relocated to three mobile home trailers. They have >>> HVAC wall-packs, so we have Heat and AC 24/7 year-round. >>> Before the move the HVAC in the one room building that housed our work >>> bench and VHF station stopped working. The 106 also stopped working. I >>> started looking at a GPSDO after the move. I picked up some 10811s and >>> Navman Jupiter TU modules with 10 KHz output, but other projects came along >>> and I lost interest in this. >>> >>> Today: >>> This fall at a hamfest I got a working TrueTime XL-DC with antenna and >>> feedline for $45, it has 1 ppp and IRIG-B, but no 10 MHz output. This >>> restarted my interest in this project. Then I got some complaints from >>> other club members that our HP Modulation Analyzer was both off frequency >>> and the deviation measurement it was giving was also wrong. >>> >>> The first goal is to have fun and learn something new. >>> >>> At the club we have 3 5340As (18 GHz), the 53131A (225 MHz), a pair of >>> 5435As that don't work, and the 106B that doesn't work. >>> The goal is to have a calibrated standard to drive all of our test >>> equipment. It should be accurate and precise enough to allow club members >>> to calibrate their own equipment. That would point to a GPSDO. A 10811 >>> for start, the 106 if I can fix it. >>> >>> At home I have several HP counters, 5340A (18 GHz), 5341A (4.5 GHz), 5385A >>> (1 GHz), 5386A (3 GHz) and a 5334B (100 MHz, dual channel, sill do TI), but >>> none are calibrated. I have a NI HPIB card I need to get working. I have >>> a HP Z3801A that I need to get a power supply for. I have several 10811s, >>> a pair of 105Bs, a Trimble 57963 board, and the simple complete Trimble >>> 57963 system. I also have a Brooks Shera board that is built, I have some >>> connectors for it on the way. >>> >>> I have a full set of time-nut toys to play with! My view is I have no >>> known working primary standards yet, so I'm starting from scratch. >>> I need to compare the Trimble GPSDO to something else. The Z3801A or >>> Brooks Shera's board controlling a 10811 or one of the 105Bs. >>> >>> Thanks >>> >>> Robert >>> >>> On 12/26/2019 11:51 PM, Robert DiRosario wrote: >>>> I am trying to calibrate some equipment at the amateur radio club at work, >>>> and my stuff. We have an HP 5340A with a 10811 inside. It must have been >>>> upgraded at some point in the past, the display uses Nixie tubes. I >>>> calibrated it c2000 using a HP Cs standard. That lab and it's equipment >>>> are gone. :-( >>>> >>>> From ebay / China I got a simple GPSDO that uses a Trimble 57963 inside. >>>> I use the output of the 10811 in the 5340A to drive an HP 53131A. I then >>>> measured the 10 MHz output of the GPSDO using the HP 53131A and got >>>> 10,000,000.08 Hz. >>>> >>>> Assuming the GPSDO is correct, is 0.08 Hz drift over 20 years a reasonable >>>> amount of drift for an 10811? >>>> >>>> I have an HP Z3801A, once I get a power supply for it I can check the >>>> other GPSDO. >>>> >>>> Thanks >>>> >>>> Robert >>>> KA3ZYX >>>> >>>> __________________ >>> On 12/26/2019 11:51 PM, Robert DiRosario wrote: >>>> I am trying to calibrate some equipment at the amateur radio club at work, >>>> and my stuff. We have an HP 5340A with a 10811 inside. It must have been >>>> upgraded at some point in the past, the display uses Nixie tubes. I >>>> calibrated it c2000 using a HP Cs standard. That lab and it's equipment >>>> are gone. :-( >>>> >>>> From ebay / China I got a simple GPSDO that uses a Trimble 57963 inside. >>>> I use the output of the 10811 in the 5340A to drive an HP 53131A. I then >>>> measured the 10 MHz output of the GPSDO using the HP 53131A and got >>>> 10,000,000.08 Hz. >>>> >>>> Assuming the GPSDO is correct, is 0.08 Hz drift over 20 years a reasonable >>>> amount of drift for an 10811? >>>> >>>> I have an HP Z3801A, once I get a power supply for it I can check the >>>> other GPSDO. >>>> >>>> Thanks >>>> >>>> Robert >>>> KA3ZYX >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- [email protected] >>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>> and follow the instructions there. >>> On 12/26/2019 11:51 PM, Robert DiRosario wrote: >>>> I am trying to calibrate some equipment at the amateur radio club at work, >>>> and my stuff. We have an HP 5340A with a 10811 inside. It must have been >>>> upgraded at some point in the past, the display uses Nixie tubes. I >>>> calibrated it c2000 using a HP Cs standard. That lab and it's equipment >>>> are gone. :-( >>>> >>>> From ebay / China I got a simple GPSDO that uses a Trimble 57963 inside. >>>> I use the output of the 10811 in the 5340A to drive an HP 53131A. I then >>>> measured the 10 MHz output of the GPSDO using the HP 53131A and got >>>> 10,000,000.08 Hz. >>>> >>>> Assuming the GPSDO is correct, is 0.08 Hz drift over 20 years a reasonable >>>> amount of drift for an 10811? >>>> >>>> I have an HP Z3801A, once I get a power supply for it I can check the >>>> other GPSDO. >>>> >>>> Thanks >>>> >>>> Robert >>>> KA3ZYX >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- [email protected] >>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>> and follow the instructions there. >>>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>> and follow the instructions there. >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
