This circuit for UHF between 800 and 1 000 MHz was found in an American documentation from the 90's. The integrated circuit is from that time, uncommon today.
This simple metronome, from 1985 documentation uses only transistors and has two settings. For...
This circuit is suitable for modulating AM transmitters. The circuit is from a 1977 radio amateur...
This flasher was found in an old Hands On, but uses common components. The optocoupler can be...