A tachometer using solid state and/or vacuum tube circuitry.
NSN 5895-01-462-8836
NSN 5999-01-441-7707
NSN 5960-01-355-2968
NSN 5835-00-332-3274
NSN 6685-01-094-6455
NSN 5855-00-197-6387
NSN 6620-01-514-2949
NSN 5930-00-865-1599
NSN 5895-00-798-5798
NSN 6150-01-173-9875
NSN 5930-01-143-9666
NSN 6110-01-582-1370