A tachometer using solid state and/or vacuum tube circuitry.
NSN 5996-01-004-7832
NSN 5910-00-087-3914
NSN 6220-01-485-8464
NSN 5855-00-916-2236
NSN 5975-01-131-8057
NSN 5999-00-406-1325
NSN 6145-01-270-5485
NSN 5998-00-252-5688
NSN 6320-01-652-3806
NSN 5960-01-219-5504
NSN 5855-01-241-1054
NSN 5895-00-008-8272