A tachometer using solid state and/or vacuum tube circuitry.
NSN 6150-01-242-3298
NSN 6685-01-413-6487
NSN 5960-01-416-6187
NSN 5990-00-784-1254
NSN 5915-01-084-8696
NSN 5915-00-267-9857
NSN 5990-01-115-9488
NSN 5935-01-449-2874
NSN 5990-00-155-2306
NSN 5960-01-052-6997
NSN 5905-01-340-8561
NSN 6105-01-574-5913