A tachometer using solid state and/or vacuum tube circuitry.
NSN 2925-01-446-6523
NSN 5905-01-468-0555
NSN 5945-01-164-5111
NSN 6240-00-383-7668
NSN 6610-01-128-7748
NSN 6150-01-373-8628
NSN 6610-01-544-3734
NSN 6150-01-441-2626
NSN 6135-00-267-9432
NSN 5935-01-633-1902
NSN 7035-01-068-5077
NSN 6110-00-248-7475