early GEC transistor radio


Posted on Feb 4, 2014

The world`s first practical crystal amplifying device, in 1948, and the dawn of the commercially available Transistor Radio in Britain. If I had been an average radio enthusiast or constructor at that time then I would have been coming to terms with the new miniature all glass valves, learning about the possibility of new TV channels or reading


early GEC transistor radio
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about how to incorporate strange FM circuitry into the Domestic Wireless set. However, if I had also followed the accounts from America, since its introduction, of this exotic device called a Germanium Triode and had been further tantalized by snippets in the radio press referring to its experimental production by British companies and also harboured a desire to build a circuit using it, what would have been available to me in terms of circuits or guidance First let us put down a few mile posts so we can see exactly where we are in the scheme of things. What had been officially announced in June 1948 by Bell Telephone Laboratories was a Point Contact Transistor. Journals subsequently referred to it quaintly as a Germanium Triode or a Crystal Valve. It had many drawbacks and wayward characteristics but it worked and it paved the way for other devices. Amongst early contenders in the field in the U. K. were British Thompson Houston and G. E. C. both of which appear to have produced point contact transistors in 1948 and there is new evidence from France to challenge the Bell claim that they were the sole inventors (see postscript). In 1951 Shockley at Bell announced a working junction transistor and the following year they were available commercially in pilot quantities in the United States. The junction transistor was a much more predictable beast but its Achilles heel initially was its poor frequency response. However...




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