[Milsurplus] Mechanical Modulator

[WB6BLV (DM06)]

The 'wobulator' I mentioned is not connected mechanically to any other
parts... it is nothing more than a variable capacitor driven by a voice coil
(as in a pm speaker); the voice coil displaces one of two plates (or one set
of two sets of plates in larger units) of the internal capacitor.  Audio fed
to the voice coil causes the capacitance of the wobulator to vary at the
frequency of that audio.  Being a mechanical device, the band of frequencies
to which the voice coil can respond is limited to the low audio spectrum.
Not bad for '30s amd early '40s technology, though, huh?

Anybody know of wobulators being used in anything besides the APN-1??

John
WB6BLV at inreach.com