A tachometer using solid state and/or vacuum tube circuitry.
NSN 6645-01-113-6712
NSN 6645-01-442-4032
NSN 5935-01-397-3531
NSN 5835-01-192-4165
NSN 6320-01-160-0416
NSN 6220-01-603-1020
NSN 4140-01-343-2887
NSN 6685-01-262-1627
NSN 6240-01-085-6576
NSN 5915-01-321-0284
NSN 6145-00-904-7563
NSN 6105-01-495-0623