[time-nuts] US Army Frequency Standard
jfor at quikus.com
Tue Jan 24 17:29:31 EST 2012
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
> 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
> Thanks in advance,
> John H.
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