A tachometer using solid state and/or vacuum tube circuitry.
NSN 5950-00-300-0287
NSN 6105-01-487-0836
NSN 6685-01-291-6972
NSN 6220-01-352-0396
NSN 5935-00-864-7570
NSN 6150-01-445-7690
NSN 5930-01-133-5714
NSN 5915-00-221-2391
NSN 6610-00-564-9360
NSN 5996-01-535-9175
NSN 5935-01-432-2486
NSN 6240-01-212-3529