Offered from private radio museum, a “Crystal Receiver” in beautiful condition. Is in working condition and built in a nice cabinet of 155 x 125 x 62 mm with a bakelite cover. Has some signs of use. There are connections on top for the antenna/ground wire/coil/detector and headphones. The coil is branded D.R.P. and has 150 windings. Two more coils will be included with respectively 200 and 300 windings. The present headphones are of the brand “Polmet” and have 2000 ohms. There is a connection for two pairs of headphones. The “Crystal detector”, usually called Crystal Radio is a device which served as a detection diode in the early years of radio technology. The detector consists of a piece of lead glass crystal and a provision to press on a place of the crystal with the sharp point of a steel wire, called a “Catwhisker”. When one has found a good spot, the detector shows a rectification effect and can serve as a diode. Crystal receivers are radios which work without AC power or batteries. The necessary energy is picked up by an antenna and comes from the transmitter you are listening to. The principle of the crystal receiver was first used in 1910-1920, but these kinds of receivers can still be used. A long antenna and good ground wire are essential for the reception. The whole set will be shipped by registered mail.