A tachometer using solid state and/or vacuum tube circuitry.
NSN 5950-01-557-4828
NSN 2925-01-463-8856
NSN 5925-00-236-9000
NSN 5930-01-487-6597
NSN 5930-00-109-0604
NSN 5935-01-396-4861
NSN 6220-01-227-5999
NSN 6220-01-465-6405
NSN 5975-01-412-4237
NSN 6320-00-228-5678
NSN 5998-01-364-0243
NSN 2925-01-425-7087