On Sat, 22 Aug 2015 18:25:04 -0400, you wrote: >rbenward at verizon.net wrote: "See below, here is a 73090 >OCXO (same as on some of those GPSDO boards) powered by +12V." > >You are incorrect in your assumption that the link you have >supplied shows a 73090 OCXO powered by +12VDC. The BOARD is >indeed powered by 12VDC (or 15VDC if you read the listing) >but if you look at all the photos you will see a 3-terminal >regulator on the bottom of the pc board.
Hi, It does indeed have a reg, but as far as I can see it's a 7812 that's in the picture in the listing. This would also explain why it has a 12V or 15V selector link. I'm not suggesting that it's a 12V osc - on my 57963-80 it is definitely fed just 5V from the regulator. I also used 6V for the power supply. It also appears just to be a basic, fast warm-up AT OCXO, which fits in with the short time constant on the GPS control loop. Angus. >The Trimble GPSDO I'm supplying 6.3VDC to had a 5 volt regulator >that has a measured output of 5.00VDC and the supply pin on the >oscillator had that 5.00VDC on it, not the 6.3VDC from my supply. >A continuity check shows a direct connection from the regulator's >5 volt output directly to the oscillator's supply pin. Because >of the higher current drawn by the 5 volt oven, running the input >to the board at 12VDC and wasting all that power as heat would >not be wise. 6.3VDC makes me happy and they chose a LDO regulator >for a good reason. > >The one error I did notice is I said the board locked after it >found satellites but that is incorrect. It does find satellites >quickly but takes about 10 minutes to lock and that is when the >10Mhz output is enabled. I did some of my checking around 1AM >and that is not a good time for clear thinking or writing. > >-Arthur >_______________________________________________ >time-nuts mailing list -- [email protected] >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
