ACK Technologies A-30 Encoder Click here to purchase or contact the seller of this item on eBay
Current Price: 58.00 USD

Ser # 34985  # 27734  Mod 2

Mod 2 isolates all internal grounds from the chassis case, ground only available on pin 15 of connector.  I believe this helps prevent ground loops.

One of them has a long cable attached and the mounting bracket as if it was removed from service salvage? Or, it's wired and ready to go and can include the paper manual. The second one looks similar, the serial number a little earlier. A plastic air hose would normally connect to the center of the unit for accurate static venting of the barometric pressure.

From my dad's vast Arcamex Avionics collection