This circuit was obtained from Elektor magazine and published in the Encyclopedia of Electronic Circuits Vol 5 of 1995. Transistors are RF types that are still common today.
This is the receiver for the previous circuit. The audio amplifier supports equivalents. The...
The 74123 TTL integrated circuit consists of a monostable that can be configured to generate...
This circuit is from a 1976 technical documentation, and there may be difficulties in obtaining the...