A tachometer using solid state and/or vacuum tube circuitry.
NSN 5998-00-647-1225
NSN 6610-01-052-0803
NSN 6150-00-240-8024
NSN 6645-01-134-2976
NSN 6685-01-575-2800
NSN 5965-01-286-4341
NSN 5895-01-045-3201
NSN 5945-00-444-6701
NSN 5905-01-570-3421
NSN 6150-00-787-5668
NSN 5998-01-537-0150
NSN 6145-00-825-7316