A tachometer using solid state and/or vacuum tube circuitry.
NSN 5925-01-204-6096
NSN 6610-01-033-1748
NSN 6150-01-597-8757
NSN 6135-01-022-5427
NSN 6110-01-054-6803
NSN 6240-01-585-3611
NSN 5925-01-542-5622
NSN 5999-01-041-8801
NSN 5990-01-303-0564
NSN 6645-01-421-6909
NSN 5960-01-294-2397
NSN 6610-01-576-6796