Uploaded November 2012 | Updated September 2026, 2 hours ago
I took a break from other projects, and wound an antenna for a broadcast receiver. The tuning capacitor came out of a junk pile, and either a Ge or hot carrier diode works as a detector. Normally, with a crystal ear piece, that's all you need to listen to the radio. To drive a normal speaker, I used an audio amplifier instead, which consists of a JFET to keep input impedance high and a LM386 audio power amplifier IC.
I took a break from other projects, and wound an antenna for a broadcast receiver. The tuning capacitor came out of a junk pile, and either a Ge or hot carrier diode works as a detector. Normally, with a crystal ear piece, that's all you need to listen to the radio. To drive a normal speaker, I used an audio amplifier instead, which consists of a JFET to keep input impedance high and a LM386 audio power amplifier IC.
