Archivo: Heliogen medium wave galena radio

Descripción: A medium wave crystal radio receiver, manufactured by Heliogen in Germany, 1935. The coil of wire (left) is the tuning coil. It can be unplugged and replaced with different coils to cover different radio bands. It is wound in a "basket-weave" pattern to reduce resistance at radio frequencies. In front of it in the glass tube is the cat's whisker detector, consisting of a crystal of galena touched by a fine wire, which extracts the audio signal from the radio frequency carrier wave. In front of that is the tuning knob, connected to an adjustable capacitor which is used to tune in different stations.
Título: Heliogen medium wave galena radio
Créditos: Fotografía propia
Autor(a): Badseed
Permiso: Puedes usar la licencia que prefieras.
Términos de Uso: Creative Commons Attribution-Share Alike 3.0
Licencia: CC BY-SA 3.0
Enlace de Licencia: https://creativecommons.org/licenses/by-sa/3.0
¿Se exige la atribución?: Sí