A tachometer using solid state and/or vacuum tube circuitry.
NSN 6650-01-191-1669
NSN 7035-00-007-5188
NSN 7035-01-506-8898
NSN 5999-01-186-0407
NSN 6620-00-343-8229
NSN 5925-00-931-6138
NSN 5930-00-237-5956
NSN 5905-01-339-9549
NSN 5960-01-290-2604
NSN 2925-01-620-9673
NSN 6240-00-150-6754
NSN 5965-01-261-0569