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.
This circuit using only transistors was obtained from Ferranti's 1969 documentation. It can be...
This sensitive circuit can be designed with FETs such as BF245 and MPF102. The sensor is a silicon...
Found in Popular Electronics from the 90s, this circuit generates two tones that are selected by a...