Found in a 90s Popular Electronics, this mixer can be expanded to more channels. Transistors can be modern general-purpose equivalents.
This 1956 direct amplification radio circuit was found in a documentation from Sylvania that...
This conventional oscillator with the 741 can be precisely adjusted to produce a 400 Hz signal. The...
This circuit uses two diodes in a doubling configuration to receive medium-wave range signals. The...