Stereo FM Transmitter (CB8459E)

This circuit was found in a 90s Radio Electronics. The FM encoder or multiplexer is an uncommon component today.

Passage Alarm (CB19986E)
The sensor of this circuit can be any phototransistor and the SCR can be the TIC106. The circuit and...
Current Regulator LM117 (CB14301E)
We found this circuit in the Linear Applications Handbook of the National Semiconductor of 1994....
Variable space mark generator 2N2646 (CB23924E)
Using the well-known 2N2646 that was popular at the time, this circuit was found in Radio...