![]() The development of a Raytheon silicon transistor was initiated by Ivan Getting soon after he joined Raytheon in 1951. “There was a radio design section that contacted all of the radio manufacturers – Warwick, Emerson, Zenith, you name it. Speaking to the success of Texas Instruments in the market place Roger Webster, who worked on the Regency TR-1, strongly endorsed the advantage of being first to have its transistors in the first transistor portable and the credibility it gave his company. Raytheon was active with its own range of transistor receivers having introduced the FM101A, T100, T150 and T2500. In 1957 Texas picked up Bulova from Raytheon and Raytheon obtained Firestone. Texas stayed well ahead supplying Admiral, Columbia CBS, Halicrafters, Magnvox, Motorola, Sentinel and Westinghouse. General Electric had a similar customer count. Raytheon did better in 1956 and by the end of that year it was supplying Bulova, Dewald, Emerson and Hallicrafters. Both these manufacturers had RF transistors in late 1954 before Raytheon announced its entrants. This shows that Raytheon did not have a market leadership role: in 1955 the only third party suppliers were Texas Instruments and Sylvania. ![]() They were after me for transistors.” īy the end of 1955 the following transistor portables were on the market as shown in the table with their principal transistor supplier: Norman Krim confirms the problems of supplying RF transistors talking to Michael Woff: “Radio Shack was in Boston at the time, and they were able to get radios from Japan but they couldn't get transistors at all. The majority of Royal 500 sets were equipped with Sylvania transistors which they sold to manufacturers at a lower price than did Raytheon. “This expedient was necessary to enable us to produce sufficient quantities by using transistors from many sources” according to its service manual. ![]() For example, Zenith produced its Royal 500, a seven transistor pocket sized set launched in November 1955, with four chassis types to accommodate four different transistor line-ups: one supplied by Raytheon (CK760 & CK759)) two supplied by Sylvania (2N94 and 2N194 & 2N193) and one by Texas Instruments (2N145). Raytheon put little energy into promoting its RF transistors: this was because demand outstripped supply, a feature of the market in general. In order to promote the new portable to a public that had no exposure to transistors Raytheon gave away cards with a genuine dud transistor saying “Take this actual sample of an electronic miracle!” with an explanation of the benefits of transistors in the new set. The April '55 review of the Regency TR-1 found the $49.95 TR-1 to be a toy-like novelty which didn't come at a toy-like price, and stated that, "the consumer who has been waiting for transistor radios to appear would do well to await further developments before buying."The July '55 review of the Raytheon 8TP gave the set high marks: "The transistors in this set have not been used in an effort to build the smallest radio on the market, and good performance has not been sacrificed to attain this end." The 8TP series was ranked high in nearly all categories, "falling down only in sensitivity."” “The April and July 1955 issues of Consumer Reports separately put these two radios to the test, and concluded that Raytheon had every reason to call its 8TP the first serious transistor radio. Base width was controlled by monitoring electrical characteristics of the junctions as alloying proceeded. In 1956 George Freedman developed a method of controlling base width by starting with a wafer that included a PN junction and fusing an electrode containing a P impurity to an exposed N layer. (This geometry gives a stronger wafer than if the notches were cut parallel). Herman Nowak developed a method of obtaining alloy junction transistors with base width of only 1 mil by milling notches set at right angles on either side of the wafer and creating the base junction at the intersection of the notches. ![]() Raytheon research into improved RF performance focussed on methods to reliably reduce the base width of its transistors. Other than the above parameters, all the transistors in this range had identical specifications suggesting that they were made, tested and selected. The CK760 was adopted as a universal RF transistor and initially was used in all stages of the 8TP receiver in its first configuration. Notably the CK759 was not included in the initial release and may have been introduced later as a means of utilising low specification transistors that were usable as IF amplifiers. ![]()
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