This circuit is from the September 1985 issue of Radio Electronics magazine. The circuit has an LED charge indicator and is based on CMOS logic. The MOSFET must be equipped with a heat sink.
This circuit, from a 1973 documentation, can be made with BC549 transistors. The frequency depends on...
Suggested by General Electric in a 1965 documentation, this circuit can use the TIC106 as an SCR....
This circuit is from an old Popular Electronics. The circuit is based on a 555 and a 5V voltage...