In the figure we have two circuits of limiters that provide the cut of the negative peaks of a signal. The circuit is from an 80's telecom documentation being adaptable on common receivers.
This circuit, from a 1987 documentation, is for the CB3817E transmitter. Connected to the handset...
This circuit is from a 1975 technical documentation on filters. The FET can be a BF245 and the...
This circuit uses a sensitive 9V relay but can be built with 6 or 12V relays by changing the power...