6 V power supply with power zener (CB21531E)

This circuit provides 6.3V of output from a 9V input. The circuit was found in a Dutch publication from 1966.

Remote control analyzer (CB7812E)
Found in a 90s Popular Electronics, this circuit checks if a remote-control transmitter is...
Different 555 blinker (CB25116E)
This circuit for a decorative robot was found in the April 1988 Radio Electronics magazine. The...
Siren (CB21738E)
This siren circuit was found in a Popular Electronics from March/April 1969. We can easily...