Project XTAL Radio – Schematic Diagram
Key:
capacitor - variable
diode
inductor
earphone
wires connected
wires not connected
antenna
ground
The above schematic diagram shows the electrical wiring of the crystal radio. Schematic diagrams are used by
people involved in the assembly and/or trouble shooting of electronic devices. The arrow on the coil represents
an adjustable connection to the coil.
Follow the flow of the signal through the radio with the schematic diagram. The radio wave is received by the
antenna, flows through the antenna coupling capacitor (
C2
) and then into the tuning circuit. The tuning circuit is
made of an inductor (
L1
) and a tuning capacitor (
C1
). Adjustment of the tuning capacitor (
C1
) selects the
desired station. The selected signal flows into the diode (
D1
) which functions as a detector. A detector separates
the audio signal from the selected radio signal. The audio signal flows into the earphone where electrical energy
is converted into mechanical energy. This particular mechanical energy is the sound waves received by our ears.
