A tachometer using solid state and/or vacuum tube circuitry.
NSN 6240-00-905-6050
NSN 5975-00-343-9466
NSN 5930-00-636-8888
NSN 6610-01-487-2625
NSN 5960-01-580-6360
NSN 5950-01-542-7404
NSN 6645-01-052-8331
NSN 4140-01-354-1228
NSN 5998-00-597-7175
NSN 6130-00-908-0141
NSN 5996-00-050-6570
NSN 6650-00-736-8456