I just finished building my Raudive Diode, and with a few minor tweaks it is the same as the original Diode made by Konstantin Raudive a Latvian psychologist and philosopher. Below is a picture of the Raudive Diode I built.
The Germanium Diode which is the major part of the Raudive Diode is essentially a non-physical microphone used in place of a physical microphone. The Germanium Diode acts as a microphone picking up only EVP's and not recording any ambient sounds (depending on the recorder used, when an external mic of any kind is plugged in, the recorder automatically shuts off the internal mic).
The copper disk mounted to the top is used as an antenna as its wired directly into the board containing the Germanium Diode. I believe copper is a better conductor rather than chrome or insulated wire. As you can see it plugs directly into the mic in or input socket on the recorder via a 3 foot cord.
I use Zoom H2N recorders to plug these into during investigations, and let them sit constantly recording for the entire investigation. Also visit my online store for other paranormal investigating equipment.
