Ad
related to: galena crystal radioebay.com has been visited by 1M+ users in the past month
Search results
Results from the WOW.Com Content Network
Indian physicist Jagadish Chandra Bose was first to use a crystal as a radio wave detector, using galena detectors to receive microwaves starting around 1894. [28] In 1901, Bose filed for a U.S. patent for "A Device for Detecting Electrical Disturbances" that mentioned the use of a galena crystal; this was granted in 1904, #755840. [ 29 ]
Galena cat whisker detector used in early crystal radio Precision crystal detector with iron pyrite crystal, used in commercial wireless stations, 1914. The crystal is inside the metal capsule under the vertical needle (right). The leaf springs and thumbscrew allow fine adjustment of the pressure of the needle on the crystal.
It was used as the crystal in crystal radio receivers, in which it was used as a point-contact diode capable of rectifying alternating current to detect the radio signals. The galena crystal was used with a sharp wire, known as a "cat's whisker", in contact with it. [28] In modern times, galena is primarily used to extract its constituent minerals.
Bose's 60 GHz microwave apparatus at the Bose Institute, Kolkata, India. His receiver (left) used a galena crystal detector inside a horn antenna and galvanometer to detect microwaves. Bose invented the crystal radio detector, waveguide, horn antenna, and other apparatus used at microwave frequencies.
Cell phones, digital radio and digital television use more complex modulation and demodulation systems. The simplest AM receiver is the Crystal Set or Crystal Radio. Demodulation is achieved by a semiconductor diode. One of the earliest forms of detection consisted of a thin copper wire in contact with a small chunk of Galena Rock.
The first instrument used to access radio signals were crystal sets which used a tiny piece of galena (lead sulfide) called a “cat's whisker” to detect signals. The challenge with these sets were tuning into specific stations, though they were inexpensive and easy to make.
Discover the latest breaking news in the U.S. and around the world — politics, weather, entertainment, lifestyle, finance, sports and much more.
Prior to the introduction of the Audion, radio receivers had used a variety of detectors including coherers, barretters, and crystal detectors. The most popular crystal detector consisted of a small piece of galena crystal probed by a fine wire commonly referred to as a "cat's-whisker detector". They were very unreliable, requiring frequent ...
Ad
related to: galena crystal radioebay.com has been visited by 1M+ users in the past month