A tachometer using solid state and/or vacuum tube circuitry.
NSN 5999-00-263-3328
NSN 5950-01-226-3055
NSN 6320-01-426-8947
NSN 5905-00-577-0798
NSN
NSN 6110-01-497-0112
NSN 5998-01-137-1034
NSN 5996-01-415-3098
NSN 5935-01-424-9250
NSN 5990-00-660-8885
NSN 5950-00-588-2518
NSN 5960-01-046-2821