A tachometer using solid state and/or vacuum tube circuitry.
NSN 5925-01-602-8068
NSN 5895-01-581-3359
NSN 6620-00-383-8740
NSN 5945-01-160-6247
NSN 6220-01-517-2365
NSN 5915-00-737-0924
NSN 5855-00-167-7893
NSN 6645-01-398-2505
NSN 5998-01-142-3072
NSN 5920-01-037-1078
NSN 5910-00-541-1381
NSN 5950-01-485-2595