This page is about vintage semiconductor devices made by Texas Instruments (TI), a US company, but the series described below were produced only in the UK. They do however, bear the standard TI logo shown on the right. There seem to be some discrepancies in the dates given in various accounts on the Web, but TI opened a facility in Manton Lane, Bedford in 1960 (or possibly a few years earlier) to supply semiconductors to Britain and Western Europe.
For whatever reason, TI in the UK manufactured several unique series of devices, in addition to selling US types. In common with the parent company's strategy, manufacture quickly moved from germanium to silicon. I have a 'Product Summary' booklet that describes their devices, dated February 1965. I do not believe that the UK types were offered for sale in the USA.
I do not possess all the transistors and diodes described below, in fact I am seeking some of them. It is noted in the text where I am seeking examples of any particular type: if you have some for sale or exchange, please
I do not believe that TI manufactured any germanium diodes, in either the UK or the USA. If they did, in the UK they would have part numbers beginning with 1G. (Beware that SGS in Italy made some 1Gnn diodes). if you know of any such TI device, please
As far as I am aware, TI in the UK started by manufacturing germanium transistors in the 2G series. Most of these use the VASCA SO-2 encapsulation, such as the 2G302 shown. These include:
- 2G301, 2G302, 2G303, 2G304 and 2G306 general purpose and switching PNP types
- 2G308, 2G309, 2G371, 2G374 and 2G377 general purpose amplifier PNP types
It is common for many of these part numbers to have an additional suffix letter, for example 2G371B. I suspect that this denotes gain banding.
Some of these transistors were commonly used in the UK as general-purpose AF types similar to the famous Mullard OC71.
A few high-voltage germanium types, 2G383 to 2G387, use the JEDEC TO-5 can. I do not have any of these, if you know where I can obtain examples, please
TI in the UK certainly did make silicon diodes, in the 1S series. In fact they made a large number of types in this series. My image shows the 1S001, which I presume is the first. It uses the VASCA SO-16 case.
The D.A.T.A. book "Semiconductor Diode & Rectifier Characteristics Tabulation 1961 vol VII", published not long after the Bedford plant opened, lists the following for T.I. England:
1S001 to 1S005, 1S111 to 1S115, 1S121, 1S207 to 1S218, 1S301 to 1S303, 1S401 to 1S405, 1S501 to 1S518, 1S600 to 1S604, 1S610 to 1S614, 1S701, 1S704, 1S914, 1S916, and another 15 types 1S50nn. The 1965 Product Summary lists many more 1S types!
TI UK then went on to silicon transistors in the 2S series. The 1965 Product Summary structure suggests, but does not explicitly state, that some of these groups were now obsolete and replaced by 2N types. It includes the groups:
- 2S001 to 2S005, 2S014, 2S101, 2S131, 2S401, 2S701 to 2S704, 2S741 to 2S746 : NPN low-power amplifiers and switches
By this time they had, with some exceptions, standardised on JEDEC encapsulation, as this 2S001 in the TO-5 can shows. Only some early types are painted black, later ones are unpainted for better heat dissipation. They bear a three-digit code, the significance of which is not definitely known to me, but I guess at YWW where Y is the year in the 1960s and WW is the week number in the year. My 2S001 is coded 008 which would be week 8 of 1960. If you can definitively explain the code, please
- 2S012, 2S012A, 2S013, 2S013A, 2S721 to 2S724 : NPN high-power
Early power transistors in the 2S series use a case that TI designated MS3, which became JEDEC outline TO-53. It has a square flange and unusual hooked pins, as shown for this 2S012, an AF amplifier. As far as I am aware, this is unique to TI. Again, some may be unpainted.
- 2S017 to 2S020, 2S711, 2S712 : NPN medium power (in TO-5 cans).
- 2S501 to 2S503 : NPN low-level low-noise amplifiers.
These few low-level low-noise types use the JEDEC TO-18 can.
- 2S306, 2S307, 2S326, 2S327 : PNP chopper.
- 2S301 to 2S305, 2S321 to 2S325 : PNP low-power general-purpose.
- 2S024 to 2S026 : NPN high-power in the square TO-53 outline.
I have this 2S036 in the JEDEC TO-3 encapsulation that became the standard for power transistors. However, it is missing from the 1965 'Product Summary' and also from the various D.A.T.A. publications on the Web. The code 747 suggests it may have been manufactured in 1967. It is listed in the 1969 book 'Kristalldioden und Transistoren Taschen-Tabelle' published by Franzis-Verlag in Muenchen.
I'm aware of the existence of similar TO-3 types 2S033, 2S034 and 2S035. I have no data for any of these.
TI Bedford also made a small number of grown-diffused silicon tetrode transistors, types 3S001 to 3S003. These were intended as amplifiers up to 30 MHz. They used the standard TO-5 can, shown painted black on my original data sheet. I do not have any of these, if you know where I can obtain examples, please
Texas UK also had transistors registered in the UK military CV series as shown by this CV7061, equivalent to 2S012A (a high-power NPN silicon AF amplifier). It is coded KB/NQ and datecoded TC for March 1962. The K means that it has been manufactured to specification, the B indicates that approval was given by UK authorities, and NQ is the factory identification code for TI Bedford.
According to the D.A.T.A. book "Transistor Characteristics Tabulation 1962 Vol XII" the Bedford plant also manufactured a fair number of 2N series transistors. However they have the same part numbers as ones made by TI in the US and I am unaware of any way to distinguish them.
They also made some silicon Zener diodes in the 1N series, but I think they have the same identification difficulty.