Found in a 1968 Texas Instruments documentation this circuit uses an SCR from that time. Modern equivalent types can be used for a higher power version.
This circuit is from an old technical documentation from Spain. The circuit uses a FET that is...
Found in a documentation from the 90's, this circuit already includes an amplification stage. The...
This circuit, called Kames Dandy, can mix signals from a wide range of frequencies and is...