Arthur, You are correct, I missed that regulator, but may other Trimble oscillators are powered by +12V. That's what led me down the wrong path. I still suspect that it might have been designed for +12V, as +6.5V is not a common supply rail.
I just got my Trimble board yesterday and hope to have it running this week. I am still wrestling with my Z3801, trying to get it to run with a Morion MV89, but then that crapped out. Now trying to get it to work with a Efratom OCXO. Bob >>> -----Original Message----- >>> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Arthur >>> Dent >>> Sent: Saturday, August 22, 2015 6:25 PM >>> To: time-nuts@febo.com >>> Subject: [time-nuts] Trimble GPS board >>> >>> 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. >>> >>> 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 -- 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.