[ARC5] Aircraft mystery amplifier ID

[Michael Kana]

Hi all
I found what looks to be a WWII or later “black box” amplifier made by Pioneer Instruments/Bendix
It has a USN acceptance stencil, and 4 canon plugs. Inside are 3 6SN7s and 2 6H6. The box is marked 26vdc 110v 400 cycles
I suspect this is some form of instrumentation amplifier or audio?  
The fact it had three audio amplifier tubes got my attention….

Thx 73
Mike
AA9IL

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