A tachometer using solid state and/or vacuum tube circuitry.
NSN 5990-01-186-6446
NSN 5930-01-634-0659
NSN 6240-01-035-8525
NSN 5935-00-111-1984
NSN 6110-01-073-0088
NSN 5935-00-504-5968
NSN 5835-00-111-2953
NSN 5930-01-171-0702
NSN 5998-01-609-7922
NSN 6320-01-341-9126
NSN 5935-01-240-2374
NSN 6240-01-550-0885