This receiver was found in a 1924 book by Gernsback. The circuit uses three tubes and is powered by 3 batteries of different voltages, common at the time.
This circuit was found in a 1967 American documentation. The circuit uses components of the time,...
This circuit for several frequencies was obtained in an American documentation from the 90s. The...
We found this circuit in a Popular Electronics of the 80's. The circuit can be used to drive...