Found in a 1968 US publication, this circuit can operate on any power grid. The thickness of the wire depends on the load current.
This partial circuit that must be added to a preamplifier output transistor as in CB19186E...
This circuit was found in a 1977 documentation. With it we have the direct indication, through LEDs...
27 MHz Transmitter (CB14008E) This circuit was found in a Japanese publication from the 1970s. The...