A tachometer using solid state and/or vacuum tube circuitry.
NSN 6610-01-605-2451
NSN 6145-01-581-2744
NSN 5835-01-192-4165
NSN 2925-01-063-7876
NSN 6105-01-326-8985
NSN 6650-00-266-6808
NSN 5965-01-028-6206
NSN 6610-00-848-4764
NSN 6685-01-027-7061
NSN 4140-01-421-4045
NSN 6610-00-832-3137
NSN 6645-01-569-9087