This circuit uses only transistors and was found in a 2003 documentation. Transistor 2N3055 must be mounted on a heat sink and the voltage is set to R10.
This is a rectifier for small intensity signals, and equivalent operational amplifiers can be...
This is the transmitter for the previous circuit. We found it in a 90s Electronics Now. The...
This basic circuit is from 1984 documentation. This circuit can be used as an efficient burglar alarm...