the -12 VDC is also used by the OCXO as tuning voltage! Bert Kehren In a message dated 6/12/2011 6:05:01 A.M. Eastern Daylight Time, golgarfrinc...@yahoo.com writes:
"I bougth an Thunderbolt off E-bay some time ago, to use as reference for my spectrum analyzer and signal generators. I had it connected up with a couple of power supplies and it worked as it should. Today I put together an voltage inverter to get the -12V to the GPS in order to use it with an single 12V power supply." ++++++++++++++++++++++++ The -12 requires 10 ma according to the manual but in reality probably draws about 2 ma so loading shouldn't be a problem. You didn't mention the 5 volt supply at all. The +5 VDC should be able to supply at least 400 ma and the +12 VDC 750 ma. Ripple and noise should be around 15 MV max for the +5 VDC and 20 MV for the +/-12 VDC. The -12 VDC is used for the RS-232 so if that was giving you the problem you wouldn't see anything on your com port (note it will work at -7 VDC or so) and if the +5 VDC was off you wouldn't see anything on Lady Heather. The +12 VDC is for the oven. If the unit was working before on the other supply, go back to that supply and make sure it still works to see if it is your new supply setup or maybe you accidently fried something. If it works on the old supply, connect the new supply and recheck all connections and voltages both with a meter and a scope (or your spectrum analyser) to see if there is anything unusual. -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.