This circuit uses two tubes and can be used as a domestic intercom. The circuit was found in an American Magazine published in 1950. The loudspeakers are used as microphones. The transformers and the choke are the critical components.
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This circuit uses two tubes and can be used as a domestic intercom. The circuit was found in an American Magazine published in 1950. The loudspeakers are used as microphones. The transformers and the choke are the critical components.