In this section you'll find the instuctions
about how to build an your own galena radio. Don't forget that this
kind of receivers works ONLY with a very good AERIAL
and EARTH connections, and
dont' expect from this galena radio great performances :))
(...!): The coil "BOBINA"
are 150 turns of 0,20mm insulated wire on a bakelite cilinder about
2,5cm of diameter. The 560pf variable capacitor is a standard capacitor
used in many AM receivers. In these receivers this component has always
two sections but you have to use only one. The other capacitor, a 500pf
could be a normal polyester or symilar.
As "rivelatore a galena" or "galena
detector" you could use an original one like in the left picture,
but a normal GERMANIO diode
such as an OA81 or
similars works fine.
Remeber that in this circuit you HAVE TO use a germany
diode, not the newest in SILICIO.
This because the threshold voltage of the first is 0,2V while
in the others are 0,6V, too high to detect the low radiofrequency
signals from the LC circuit..
||Use the left picture to recognize
the right component connection. Before use the original galena getector
try to insert in the circuit a normal diode, this to insure that
the receiver be able to receive some signals in the heardphone.
Only after replace the diode with the real galena detector.
Like headphone use a piezo unit
only with the max impedance possible.
For your safety don't try to connect this
receiver to any amplifier,
external power supply, electronics equipments or other electrical devices.
If you have some questions
about this project you can send me an email just
using the "How to contact me" section
in the left navigation menu.