A tachometer using solid state and/or vacuum tube circuitry.
NSN 6685-00-179-5227
NSN 5905-01-462-0057
NSN 5855-01-540-4379
NSN 6610-01-440-9913
NSN 5895-00-101-7782
NSN 5920-00-811-4405
NSN 6240-00-449-2070
NSN 5990-00-050-7693
NSN 5935-01-416-3224
NSN 5975-00-088-5127
NSN 4140-00-941-4335
NSN 5975-01-112-8700