Radio Receiver Circuit Diagram. You can build it. We have 2 circuit are.
You should be able to change the capacitance of the variable capacitor from a couple of picofarads to about 20 pf. For more crystal radio circuits simple one transistor radios and more advanced low transistor count radios. First mass produced transistor radio 1954.
This radio receiver consists of very few parts an antenna a ground a tank circuit a diode a filter and a speaker or a set of headphones.
Detection and audio amplifier output is ready to fed into speakers to be connected to. So a 22pf trimmer is a good choice to be used as vc in the circuit. Figure 2 the lm386 can be used as a tuned radio frequency receiver. All general purpose transistors should work in this circuit you can use bc549 transistors for this circuit.
