It appears to be a Test Set for the FMQ-1 Radiosonde Receiveing system. Radiosondes used audio tones to encode temperature, pressure, and humidity as audio tones and transmitted those tones to a ground station where they were demodulated and recorded.
Interestingly, this thing apparently used a tuning fork to run a synchronous motor with a disk with holes punched in it to generate the tones. I've only been able to fing the -24P manual, which is an illustrated parts list. I'd try either ArmyRadios Group on Yahoo or Milsurplus on QTH Best, -John =========== > Hi All, > > I recently obtained a curious Low Frequency Standard dating from the late > 1950s. Its output can be switched to a number of frequencies from 10 to > 190Hz, derived from a tuning fork. It is marked "Signal Corps" and "US > Army" with a type number TS-65D/FMQ-1. > > Does anyone have any information about this unit, in particular what it > was used for and why the strange negative going pulse output and specific > frequencies. > > Thanks in advance, > John H. > > _______________________________________________ > 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.