Hi All, This is quite a common oscillator, with variants used in a number of Racal receivers or offered as high stability options for Racal counters etc, but although the specs are widely available I've not found anything from Racal that might be considered to be a user manual. The manual for the Racal RA1794 receiver offers the connection information shown below..... Table 3 : 9420 Pin Connections
1 5 MHz Output relative to pin 7 2 Internally stabilized +5.~ V varactor diode control voltage 3 +7.5 V stabilized monitor output 4 +12 V supply 5 Internally stablized +2.8 Voutput 6 Varactor diode connection 7 0 V (also connected to can). Any 4920 I've seen does match the basic RF output and DC supply connections shown above, and the pin 6 information implies an option for electronic frequency control, but I've also seen comments online to suggest most units don't actually have electronic frequency control. I certainly can't recall any Racal kit using one of these with an EFC option but if it is available I was just thinking the 4920 could make a nice oscillator for a 5MHz GPSDO. Any comments would be appreciated, and a manual and/or schematic would be one heck of a bonus:-) regards Nigel GM8PZR _______________________________________________ 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.