This modulator amplifier for transmitters was found in a 1947 American book. The circuit uses an output with 4 tubes connected in parallel and in push-pull.
We found this version of the siren that makes the American police siren sound in a 1980...
This microphone circuit was found in a collection of American 80's layouts, using operational...
The integrated circuit used in this filter is like to a double 741 and must be powered by a...