Proximity Sensor (T291E)

This is a circuit from a 1977 documentation. R1 is 39k, R2 15k, R3 3k9 and C1 uF. The tube is the critical component of the project.

DC Motor Control with Direction Change (CB913E)
Up to 0.5 A DC motors can be controlled by this circuit. Direction change is achieved by a logic...
Two Transistor AM Radio (CB1453E )
This experimental circuit is from a 1975s publication. The coil consists of 80 turns of wire AWG...
Common Collector Stage (CB4937E)
This is a typical common collector amplifier step configuration. The transistor can be used...