This CW circuit was found in a Radio Amateur Today from the 890s. The CMOS circuit must be powered by an isolated source and has different dash and dot timings.
Found in a 1967 EEE, this circuit oscillates at 20 MHz according to the values of the given...
This circuit is from a 1980s Motorola documentation. The circuit can be made with modern...
This circuit is from Radio Electronics from April 1987. The circuit is powered with voltages that...