A tachometer using solid state and/or vacuum tube circuitry.
NSN 5990-01-580-2191
NSN 6220-01-203-4559
NSN 5990-00-059-8833
NSN 6135-01-562-3056
NSN 4140-01-415-0941
NSN 6620-01-550-2805
NSN 7035-01-241-2127
NSN 5855-01-109-6433
NSN 5910-01-388-2895
NSN 6145-01-324-7054
NSN 6320-01-631-7828
NSN 5965-00-100-1291