Microammeter (T465E)

Found in a 1948 MIT documentation, this circuit uses a 0 to 100 uA microammeter as an indicator. The power supply is 150 V.

Metal Detector (CB5334E)
The search coil of this detector consists of 140 turns of wire 18 in an 8 inch diameter form. The...
Segment decoder (CB6601E)
This circuit was obtained from a 1966 General Electric documentation. It can serve as a basis for...
Extremely low power alarm C106 (CB24134E)
The quiescent current of this alarm is in the order of microamps and the same is true for the...