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.
This super regenerative detector circuit was found in an English documentation from 1963. The coil...
This circuit was found in an old English publication. The circuit makes use of general-purpose transistors....
This configuration, which appears in the manual of other manufacturers, is an excellent 1.5 V...