Found in a 1966 General Electric documentation, this dimmer should only be used with incandescent lamps. The Triac is according to the power of the lamp.
This circuit using an operational amplifier was found in old American documentation. It can be...
If the circuit oscillates, emitting sound, it is because the transistor is good. This simple...
Like the previous circuit, this is used in the analog part of the telephone lines. The same...