A tachometer using solid state and/or vacuum tube circuitry.
NSN 6145-01-535-6035
NSN 5950-01-510-0538
NSN 5925-00-248-4331
NSN 5920-00-930-4063
NSN 5975-01-089-8641
NSN 5990-00-832-9766
NSN 5905-01-155-0980
NSN 5855-00-879-7245
NSN 5855-01-634-0259
NSN 5945-01-406-7773
NSN 5999-01-174-4944
NSN 5998-01-412-8054