One source of information about early Tungsram devices is an article by Simoncsics László which was published in the Hungarian magazine 'Radiotechnika' in 2016. In one paragraph he says that 'Radiotechnika' started reporting on semiconductors in 1957. He goes on to say that Tungsram's first transistors were copies of the USSR type П6, made from about 1955.
My scanned Tungsram data catalogue for 1960 lists five transistors: P13, P13A, P13B, P14 and P15. These use the same outline as the P6 but were Tungsram development, not copies of USSR types. P6 is not listed.
There are images of some of these devices on the Web. The Orionette 1004 radio uses two P14 as AF amplifiers and a pair of P6 as output transistors. (Interestingly, a schematic that I can no longer find showed the output transistors as 2P6, suggesting that a matched pair was sold). The P13 is shown on the radiomuseum site.
This image shows a P13B in an encapsulation that is very similar to early USSR transistors. I don't know why there is just a letter T rather than the Tungsram logo. I suspect strongly that the number under the part code is a date code in the format month-year, so my P13B coded 88 was made in August 1958.
I would like to obtain examples of these P types, the P6x ones in particular. If you know where I might get some, please
My scan of the Tungsram catalogue for 1963 contains some P-series types in what was to become Tungsram's standard outline for low-power transistors, a metal cylinder similar to SO-2 or TO-1.
The catalogue contains:
The original P types are not listed, so these must have superseded them. My image shows the P13AT
Tungsram made germanium transistors in the Philips/Mullard OC series, but for most of them they added 1000 to the original part number. A Hungarian data book (7.6MB pdf) from 1960 by Házman and Hrabál lists the following:
I believe that the black-painted ones are the earliest and I am seeking a black example of OC1044.
Tungsram made other transistors equivalent to OC types, starting later than 1960. The 1963 Tungsram catalog lists:
- OC1070, OC1071, OC1072.
The 1966 Romanian book 'Catalog de Dispozitive Semiconductoare' by Veronica Vătăşescu and Şerban Epure, which you can download from the Web, lists
- OC1070, OC1071, OC1072, OC1074, OC1075, OC1076, OC1077, and OC1079.
I am seeking a black OC1070 and other shapes of OC1079. If you can help with that, please
Considering now the pro-Electron numbering, I have a Tungsram catalogue for 1966 that lists the following types:
I have a Tungsram databook 'Electron Tubes and Semiconductors' from 1976 that lists some more germanium types with pro-Electron numbers and many more silicon ones.
Here is a Tungsram AC125 in the TO-1-like package. This common type is a PNP germanium alloy transistor for AF pre-amplifier applications, equivalent to the Mullard OC70 or OC71.
This is a Tungsram AC188K in the standard Telefunken outline with aluminium block heatsink, the suffix K denoting 'Kühlkörper' or 'Kühlklotz'.
And here is a Tungsram AD161 AF power type.
'Electron Tubes and Semiconductors' from 1976 lists the following Tungsram germanium power transistors:
The ASZ versions with 1000 added have lower maximum ratings than the 'original' types.
Ebay usually has a few more genuine Tungsram power types such as AD1202 and AD1203, plus some wrongly-attributed ones.
Considering now early diodes, I turn again to the Hungarian data book from 1960. It lists two series of germanium point-contact diodes by Tungsram:
These do not appear in the Tungsram catalogue, and I do not know what they look like. The naming makes me wonder if they are copies of USSR devices, if they were in fact manufactured.
If you know where I can find information about, or examples of, these GD diodes, please
These are all glass axial point-contact diodes and I believe that they are equivalent to Telefunken types without the '1000' added, for example OA1150 is equivalent to Telefunken OA150. These are shown in the images below, which show early examples with a coloured decal on the body; later examples just have black printing on the glass.
I also have some OA1154 without the Q suffix but with a green decal: I would be interested in original data for this type. The type OA1161 was sold in matched pairs denoted 2-OA1161, as shown by the rightmost image above. Possibly other OA types were too, but I have no data for such pairs. If you do, please
Tungsram made three more OA types: the gold-bonded diodes OA1180, OA1182 and OA1182D. My image shows the first of these with a rather fetching purple decal. I am seeking examples of OA1182 and OA1182D with decals on the body (rather than later examples with printing on the glass).
If you know where I can get any, please
Tungsram also made glass-bodied point-contact types in the AA, GA and GAZ series, but the 1960 Hungarian data book does not list them. The last two are Eastern European series. Tungsram's 'Electron Tubes and Semiconductors' from 1976 lists
The 1960 Hungarian data book has sections on germanium junction diodes and silicon diodes, but there are no Tungsram types listed.