Found in American documentation from the 1990s, this circuit uses coils with multiple outlets to get the best reception, the diode is a general-purpose crystal diode.
This operational clamping circuit was found in an American documentation from the 1980s. The...
This circuit produces two signals with inverted phases. One is taken for the emitter of Q1 and the...
This intercom with wires up to 30 meters separation between the stations is from the Linear...