A tachometer using solid state and/or vacuum tube circuitry.
NSN 6650-00-758-3443
NSN 6220-00-938-3890
NSN 5950-01-595-9029
NSN 2925-01-483-2389
NSN 5895-00-913-6448
NSN 7035-01-492-9466
NSN 5960-01-324-1342
NSN 5965-01-487-2713
NSN 5910-01-578-3170
NSN 5920-01-525-3629
NSN 2925-00-915-1827
NSN 6240-00-968-9274