A tachometer using solid state and/or vacuum tube circuitry.
NSN 5915-01-195-8434
NSN 5996-01-467-0580
NSN 6610-00-186-9180
NSN 5960-00-390-5670
NSN 5905-00-146-1929
NSN 5999-01-422-2962
NSN 6645-01-089-6459
NSN 6620-00-377-9068
NSN 5950-01-333-1313
NSN 6150-01-061-6779
NSN 6685-00-279-3620
NSN 6130-01-214-1645