A tachometer using solid state and/or vacuum tube circuitry.
NSN 5915-00-106-3674
NSN 5985-01-148-6524
NSN 5965-01-100-1195
NSN 5985-01-312-3047
NSN 5925-01-025-6167
NSN 6610-01-148-2181
NSN 5905-01-455-4135
NSN 2925-00-020-7524
NSN 5998-00-268-1908
NSN 5895-01-209-4904
NSN 6145-01-360-5863
NSN 5915-01-382-0517