A tachometer using solid state and/or vacuum tube circuitry.
NSN 6620-01-472-6461
NSN 4140-00-555-3856
NSN 6150-01-122-2275
NSN 6105-01-025-2571
NSN 5990-01-204-7576
NSN 5925-00-930-2265
NSN 5965-00-240-5775
NSN 7035-01-350-0824
NSN 5999-01-337-3346
NSN 5999-00-204-6171
NSN 5920-01-528-5707
NSN 6320-00-994-0179