This circuit controls the channel separation as described in the March 1973 Radio Electronis magazine article. The circuit was proposed by Mullard (Philips) and consists of two channels as shown.
We have in the figure a traditional amplifier configuration with operational amplifier. The source...
This circuit was found in a 1977 Radio Shack documentation. The circuit is TTL, which must be...
This circuit is suitable for modulating small FM transmitters for eavesdropping or espionage. The...