With this simple circuit it is possible to simulate a telephone line for carrying out repairs on telephone sets. The transformer must be 36 V and the diode can also be 1N4004.
The circuit presented, from 2006, serves to control loads at a distance, robots, etc. It can be...
This circuit is given in two versions, having been found in a publication from the 90s. The second...
I found this circuit in a documentation for radio amateurs from 1975. The FET could be the BF245....