Detector Receiver - Maker Factory ELECTRONICS EXPERIMENTS BOX Manual

2.100 Detector receiver

Circuit 212: Simple detector receiver
Setup information
Install the diode and the ceramic capacitor as shown in Fig. 2.212 followed by the jumper wire. Last but not
least connect the Piezo element. Check the placement on the board again.
You can significantly increase the sensitivity of the Piezo element by using a sound plate or even a sound
box. Read more about it in Chap. 1.2.3
Experiment
A detector receiver is a bedrock in radio technology. This receiver circuit was already used a 100 years ago.
It signature is that no battery is needed for operation. The receiver and the headphone are merely powered
by a wire antenna, which should be as long as possible. A ground connection as short as possible is made
to a water line. Assumed that you are not living in a very remote area, you would be able to listen to the
nearest strong local broadcaster on LW or MW, while at night you could possibly receive a mix of several
broadcasters.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.212.
Components required:
1 x BAT85 Schottky
diode, 1 x 1 nF ceramic
capacitor, 1 x Piezo ele-
ment, 1 x breadboard
Fig. 2.212: Simple detector
receiver
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