This circuit was obtained from Radio Electronics magazine, October 1987. The circuit uses a triac to control the heating element current. The transistors are general purpose.
This circuit was found in an American magazine 73 for radio amateurs of the 80s. It is an...
Found in American documentation from the 1980s, this circuit can be designed with equivalent...
This circuit is from a 1977 documentation. It is powered by the power supply of the circuit under...