With an 18 V input, this regulator was found in Philips documentation from the 60's. The transistors are from that time. The power transistor must have a heatsink.
Found in 1960's Radio Electronics, this circuit provides an audio tone that depends on the logic...
This circuit was obtained from an ancient American documentation. The coil consists of 80 to 100...
In a reflex receiver, the detected audio signal is applied back to the circuit input to receive new...