A tachometer using solid state and/or vacuum tube circuitry.
NSN 6130-00-875-1941
NSN 5998-01-095-4956
NSN 6130-00-150-2372
NSN 6130-00-402-0559
NSN 5935-01-316-2553
NSN 6620-00-852-5353
NSN 6145-01-531-2294
NSN 6150-01-590-0456
NSN 6110-01-447-6229
NSN 5855-01-651-1393
NSN 6645-01-076-4655
NSN 5855-00-548-4742