We found this circuit in the October 1987 Radio Electronics magazine. The triac must be controlled according to the heater. The transformer has a low current, of the order of a few hundred mA.
Using a zener diode it is possible to change the linearity of the scale of an analog instrument by...
This circuit causes the relay to be energized when the input voltage exceeds the voltage value of...
This circuit can be used in 0,5 to 37 V Power supplies and output currents up to 3 A. The...