Using a period sensor, this circuit was found in the February 1986 issue of Radio Electronics magazine. The sensor is a Philips of the period.
Found in a 90s Popular Electronics, this circuit provides a current of 3 to 5 A depending on the...
We found this circuit in the 1964 RCA transistors manual. The sensor may be a common LDR and the...
This circuit has tone control, and its power depends on the supply voltage. The circuit is from...