This circuit, with a 12 V input, was found in a Popular Electronics from the 1990s. Information is given about the ferrite-wrapped transformer. The transistor must be mounted on a heatsink.
This circuit was obtained from an American publication from the 60's. The transistors are...
This circuit detects light variations using two LDRs as sensors. Operational amplifiers and...
Using the 555 this circuit was found in a Popular Electronics from the 90's. The circuit directly...