A tachometer using solid state and/or vacuum tube circuitry.
NSN 4140-00-242-3574
NSN 5925-01-069-2201
NSN 4140-01-598-6898
NSN 6685-01-114-8047
NSN 5935-01-456-2054
NSN 5905-00-240-9213
NSN 5990-01-246-7417
NSN 6320-00-468-8421
NSN 5915-01-066-6324
NSN 5998-00-906-3109
NSN 5905-01-047-7507
NSN 5960-01-512-0233