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Brimar Ge Transistor

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Western Electric opened a small office in London in 1883. In 1925 the International Western Electric Company was bought by the International Telephone and Telegraph Company (ITT) and later became Standard Telephones and Cables Ltd (STC). STC used the brand name “STANDARD” for their valves/tubes, and from 1934 “BRIMAR”. The Brimar valve and cathode ray tube division was sold to Thorn Electrical Industries Ltd in 1960, and in 1961 there was a JV created between Thorn and Associated Electrical Industries (AEI) for the development and sale of valves, CRTs and semiconductors. According to the CV list, Thorn-AEI manufactured at Footscray, Kent, which became a large IC development and manufacturing site for STC up until its closure in 1993. However for Thorn-AEI (Brimar) it mentions manufacture at Rochester, Kent. So manufacturing could have taken place there as well.  Germanium pnp, Gain=212, Vf=149mV
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GEC Germanium Transistor Late 1950s

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    GEC first developed transistor devices at their research facility in Wembley, then transferred production to the GEC Radio Works in Coventry, where a point contact diode line had been established.  In 1956 GEC established a dedicated semiconductor manufacturing facility at School St, Hazel Grove (Greater Manchester). In 1962 GEC merged their semiconductor business with Mullard into a business called ASM (Associated Semiconductor Manufacturers), creating the UK's dominant semiconductor company of the 1960s. Mullard (Philips) owned 2/3 of the company. GEC devices were subsequently marketed as Mullard. GEC sold most of their share in 1968. Nexperia, formerly NXP (and Philips) still have an operating semiconductor facility in Hazel Grove. Decent gain and germanium, hfe=70, Vf=120mV  
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Raytheon Low Noise Subminiature Triode

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Raytheon (Light from the Gods) started in the 1920s and quickly became a major player in tube (valve) based early electronics. By 1938 they were producing miniature and sub-miniature tubes, including for early hearing aids. They subsequently became an early adopter of semiconductors, including the first commercially available transistor in 1948 (CK703). A very early licensee of Bell Labs' point contact transistor, and very quick off the mark. Raytheon continued to produce tubes for many years.  This is a low noise sub-miniature triode, introduced in 1962 that can be used as a microphone input amplifier. It looks to be designed for avionics applications, given its focus on reliability.  
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Siemens & Halske Transistor Innovation

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The Siemens brothers were industrialists from the mid 19th century, Siemens & Halske being one arm of several. At some point post WWII, the remaining entities merged into Siemens AG.  The patent shown in the image was filed in Germany in 1956 and in the US one year later. At the time the dominant transistor manufacturing technology was alloy junction. The method described in the patent was an early adoption of diffusion for creating the process layers with masking and etching, similar to the mesa transistor structure which emerged a little later in the US. Depositing metal instead of attaching gold wires, embedding the diffused layers and a protective layer on the surface would be the basis of the planar process subsequently invented by Fairchild.  Siemens first established transistor manufacturing in their electron tube facility in Munich in 1952.
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The First Telefunken Transistors

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Telefunken in Germany had been producing semiconductor rectifiers for a number of years before they developed transistors for mass production. Launched in 1953, the OC601 and OC602 were alloy junction germanium pnp transistors. Telefunken also developed S (special) versions which had attached copper heatsinks. These work but are low gain.  hfe=26, Vf=97mV. hfe=18, Vf=100mV.
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Philco Ge Transistor 2N1500

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Small changes having a big impact. Introduced in 1960, Philco had by then improved their etching process to create the thin base layer of their germanium alloy junction transistors. They then replaced the indium electrodes making the emitter and collector junctions with cadmium, giving better thermal dissipation. Due to its speed and thermal performance, it became widely used in computers of the time. These were manufactured by Philco (later Philco-Ford) at their factory in Spring City, PA. One AI processor chip now has more transistors than the first 25 years at least of the semiconductor industry!  It works, hfe (gain) is 96, Vf=273mV (so germanium).
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The Bucket Brigade

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Inside the Boss HA-5 headphone guitar amplifier from 1983. It had built in chorus and delay effects. The chorus came from the Boss CE-3 guitar pedal and used the Matsushita/Panasonic MN3207 Bucket Brigade Device and the accompanying MN3102 clock generator chip. The NEC IC on the left is an analog compander device i.e. it compresses and expands the input audio signal. The Bucket Brigade concept, developed by Philips Research Labs, had a series of on-chip capacitors between which charges moved in sequence, based on an external clock cycle. It was a precursor to the Charge Coupled Device (CCD) that was developed as the first significant semiconductor image sensor.
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Raytheon Quad OpAmp

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Raytheon sold its semiconductor operations in Mountain View CA to Fairchild in 1997. Fairchild was then a re-incarnation, not the original Silicon Valley pioneer. Raytheon had originally purchased Mountain View's Rheem in 1959, two years after it had spun out from Fairchild, led by Ed Baldwin who had moved from Hughes Semiconductors to Fairchild. Raytheon was expanding its transistor manufacturing into California through the acquisition. Like many companies, Raytheon expanded into bipolar and MOS circuits. Cyrus Madavi, who led Burr-Brown through to acquisition by TI came from Raytheon. I worked for Hughes, Raytheon and Burr-Brown.
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ASM Germanium Diode

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In 1962 Mullard (Philips) and GEC pooled their resources and facilities to create Associated Semiconductor Manufacturers. Mullard owned 2/3 of the combined business. GEC pulled out in 1969. This is a small signal diode CV7364/AAZ12, germanium, Vf=258mV.
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Alloy Junction Transistors From RCA

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Inside two RCA alloy junction transistors from the 1950s. The smaller one is a 40V/50mA pnp and the larger is a 40V/250mA, hence the thicker wires for lower loss at the higher current. The metal connecting the base is also larger to provide better heat dissipation. The base is a thin cut slice of pure n-type germanium which has indium pellets alloyed to each side creating the pnp junctions.  There was viscous white goo inside the cases which was difficult to remove.
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