A tachometer using solid state and/or vacuum tube circuitry.
NSN 6650-01-193-5911
NSN 6650-00-726-4242
NSN 6650-01-115-7981
NSN 6620-01-063-1441
NSN 6650-01-034-0897
NSN 7035-01-400-3666
NSN 5915-00-062-9409
NSN 6685-00-927-6280
NSN 6610-01-107-9584
NSN 6135-00-125-5265
NSN 5910-00-176-7695
NSN 5990-00-552-1611