East Germany is the colloquial name for the former German Democratic Republic (GDR), or in German, the Deutsche Demokratische Republik (DDR). This was the socialist state established in 1949 in the Soviet zone of occupied Germany and in East Berlin. Early semiconductor production in this country was essentially confined to one organisation, the Werk für Bauelemente der Nachrichtentechnik (WBN), or in English the "Works for components of telecommunications". WBN appears to have operated in two locations:

  • A research and development laboratory named after "Carl von Ossietzky", in Teltow near Berlin.
  • A manufacturing facility based in a chemical works, the Dralowid steatite magnesia works in Frankfurt(Oder), not to be confused with Frankfurt in West Germany.

WBN logo Early WBN transistors bear the identifying letters WBN. Later ones are marked HWF, and some IHT, to reflect changes in the names of the above facilities. Even later examples have no manufacturer name but instead just bear the logo shown on the right.

WBN appears to be related to another DDR semiconductor factory, the "Werk für Fernmeldewesen", again a "works for telecommunications", located in Berlin-Köpenick, Ostend Street 1-5. This opened in 1948, became a VEB in 1953/4, and changed its name in 1960 to "VEB Werk für Fernsehelektronik" the "Publicly Owned Operation works for television electronics", although the logo WF was retained. WF specialised in manufacturing diodes, whereas WBN made transistors.

Later, another organisation, the Röhrenwerke "Anna Seghers" Neuhaus a.R., abbreviated as RWN, made germanium power transistors, some of which I show below.

I have put this description together from various sources written in German which are unclear and possibly contradictory. The above may therefore be inaccurate and it is certainly not complete. If you know more, please

wanted Like most countries the GDR/DDR began with production of point-contact germanium diodes. They included a number in green cylindrical cases in several shapes such as types DD and GDT, and series MDnnn and RDnnn. I am seeking examples of these early DDR germanium diodes, if you know where I can obtain any, please

OA626 diode In the late 1950s and early 1960s WF made a number of series of point-contact germanium diodes using the Western OA numbering:

  • general purpose diodes OA625, OA645, OA665, OA685 and OA705
  • video detector diode OA626
  • switching diodes OA647, OA666, OA720 to OA723, OA741 and OA780

My image shows an OA626.

OA604 diode WF also made point-contact germanium radar diodes in typical cartridge cases, numbered OA601 to OA605, in the 1960s. My image shows an OA604.


WBN made cartridge diodes in smaller cases. I am only aware of two: the OA500 and OA513. I would be interested in obtaining examples of these, or data about them. If you know about them, please

O4A657 diode This extraordinary construction is the O4A657 quadruple diode, or more accurately, dual diode pair. You can see that the red cuboid is filled with a different coloured plastic, so I suspect it just contains four glass miniature diodes. They are arranged as two pairs: each pair is wired in series with one common central connection, giving three leads per pair, six leads in total. The RFT component catalogue describes it as a (ring) modulator.

WF also produced two other compound devices, the OAA646 and 2OA646 diode pairs. These seem to be just pairs of OA646 packed together.

ZA250//7 diode In 1954 WF began production of silicon point-contact diodes in two series:

  • High back-voltage diodes OA900 to OA904
  • Zener diodes ZA250/0 to ZA250/9; my image shows a ZA250/7. Oddly, the 7 is at right angles to the rest of the part number.

I would be interested in obtaining examples of the OA900 series. If you know about them, please

wanted WBN also made silicon power Zener diodes numbered ZL910 with a variety of suffixes denoting voltage, e.g., ZL910/6 for a nominal 6V 250mA Zener. I would be interested in obtaining examples of these. If you know about them, please

1NC-011 transistor Things get very interesting in 1954/55/56 when WBN produced four series of point-contact germanium transistors:

  • 1NC-010 Vce=-50V fT=1MHz - AF amplifier
  • 1NC-011 Vce=-50V fT=3MHz - AF amplifier, shown on the right
  • 1NC-012 Vce=-50V fT=6MHz - AF amplifier

  • 1NC-020 Vce=-50V fT=1MHz - AF amplifier
  • 1NC-021 Vce=-50V fT=3MHz - AF amplifier
  • 1NC-022 Vce=-50V fT=6MHz - AF amplifier

  • 2NC-010 - audio transistor?
  • 2NC-020 - audio transistor?
  • 2NC-030 - audio transistor?

  • 3NC-010 - oscillator transistor
  • 3NC-010s - switching transistor

All these types use a squat cylindrical plug-in cartridge with a bespoke socket. The earliest are unpainted with labels as the 1NC-011 in the upper part of the image shows, but later types are painted black with the part number printed on them, such as the 3NC-010 shown in the lower part (plugged into its socket).

I am very interested in original data, or examples of, any of these transistors. If you can provide any, please

Ich suche Originaldaten oder Beispiele für alle dieser Transistoren. Wenn Sie irgendwelche liefern können, kontaktieren Sie mich bitte.

OC811 transistor I'm unsure of the exact chronology, but in about 1959 WBN started to manufacture germanium junction transistors using OC81x series numbering such as the OC811 shown, initially bearing the WBN lettering but later that changed to HWF for "HalbleiterWerk Frankfurt" (Frankfurt/Oder component works). The series extended from OC810 to OC818 and all were AF types. These can be found in some early DDR transistor radios from about 1960, such as the Sternchen.

I am looking for OC81x types marked WBN, and specifically OC812 with any markings. If you know where I can get any, please

Ich suche nach OC81x Typen WBN markierte und OC812 speziell mit Kennzeichnungen. Wenn Sie wissen, wo ich jede bekommen, bitte kontaktieren Sie mich.

OC816 transistor The OC81n series also has examples with the lettering IHT such as this OC816. This stands for the "Institut für Halbleitertechnik" in Teltow which was founded in 1960, and seems to be a renaming and probably a promotion of the "Carl von Ossietzky" laboratory. I'm unsure of the exact significance of this so if you can explain this chronology, please

OC815 transistor Some of the OC81n series devices bear the WBN logo shown above rather than any lettering, such as this OC815. Presumably these are later production than the 'labelled' examples.

wanted Some of the OC81n series types have variants, marked as the LC series, using the same oval TO-22 can and also an elongated cylindrical can. These were released as 'hobbyist' types and clearly are out-of-spec examples. The only types that I know to exist are LC810 and LC815. I have neither of them and am interested to obtain examples. If you have any for sale or exchange, or have any original datasheets for them, please

OC821 transistor The WBN OC-series also went on into the range OC821-OC829. These appear to have started in the oval TO-22 shown, but switched later to a TO-9 can resembling the English GEC GET88x series. These are a mixture of medium-power (100mW) germanium PNP AF amplifier and low-frequency-switching transistors. There is also a 'hobbyist' LC824, which is an AF type with looser ratings. I am looking for OC82x series devices and the LC824, if you have any, please

OC832 transistor There are also early power types in TO-66 encapsulation, the OC830/OC831/OC835/OC836 AF amplifiers and the OC832/OC833/OC837/OC838 switching types, plus hobbyist LD830 and LD835 equivalents. My image shows an OC832. I am very interested to obtain examples of these, especially any with WBN labels/printing on them. If you have any for sale or exchange, or have any original datasheets for them, please

Es gab auch frühe Leistungstransistoren, die OC830 zu OC838 , von denen einige LD83x Äquivalente hatte. Ich bin sehr daran interessiert, Beispiele für diese zu erhalten. Wenn Sie eine zum Verkauf oder Austausch haben oder haben keine Originaldatenblätter für sie , bitte kontaktieren Sie mich.

OC871 transistor OC872 transistor There are then OC87n series types that used TO-18 cans, and some also used painted TO-44 cans. The OC871 on the right is found in both forms, my TO-18 example bears the WBN logo shown above. The OC872 on the left shows the TO-44 shape. This series contains AF and IF/RF types.

There is one equivalent LF871 hobbyist type that has different maximum ratings.

I am seeking examples of the LF871 as well as painted TO-44 versions of any of these transistors. If you can provide any, please

OC882 transistor OC882 transistor The TO-9 can is also used by the WBN OC88x series, confusingly using the same can and series numbers as GEC in England although different in prefix. These are low-power germanium PNP RF transistors for use as mixers/oscillators and amplifiers in radio and TV applications. They seem to have been first produced in painted cans, and then later in unpainted cans with an A suffix as shown.

Again there are hobbyist types LF880 and LF881.

I am looking for OC88x and LF88x series devices, if you have any, please

wanted transistor WBN made further hobbyist types, probably out-of-spec production examples, in the LA series.

  • LA25, LA50 and LA100 are AF transistors.
  • LA1 and LA4 are power transistors, 1W and 4W respectively.
  • LA30 is a 3Mz RF transistor.

I am looking for any of these, if you have any, please

OY114 diode GY111 diode The DDR also made rectifier diodes in three series:

  • OY100 to OY102 are low-current (100mA) types with different reverse voltage ratings.
  • OY110 to OY114 are medium-current (1A) types with different reverse voltage ratings.
  • OY120 to OY125 are high-current (10A) types with different reverse voltage ratings.

These diodes have later versions with GY numbering and more modern packaging (see next section). My image on the left shows an OY114 and on the right a GY111.

I possess no examples in the OY100 and OY120 series. If you know where I can obtain any, please

I'm not sure when, but at some point WBN switched to manufacturing semiconductor devices in what appear to be standardised Eastern European numbering. Devices from these series, which bear an approximate correspondence to Pro-Electron series apart from the initial letter 'G' rather than 'O' or 'A', were made in several countries (such as Czechoslovakia and Hungary):

  • the GA and GAY series - diodes
  • the GAZ series - Zener diodes
  • the GC series - low frequency transistors in standard elongated TO-18L cans.
  • the GF series - high frequency transistors in standard elongated TO-18L cans.
  • the GD series - high power transistors in standard TO-66 small 'diamond' packages.
  • the GY series - junction rectifier diodes.

These are less interesting than the earlier types, but still germanium. If you know what standards body in Eastern Europe created these series, please

GAZ14a diode Here is a GAZ14a.

I possess no data for the GA, GAY and GAZ series of diodes. If you know where I can obtain any, please

GD160 photodiode GD160 photodiode The left image shows some GC100d transistors , manufacturer unknown. The right image shows a pair of GD160 made by RWN, the Röhrenwerke "Anna Seghers" Neuhaus a.R., VEB.

GP120 photodiode This delightfully hand-made looking device is a GP120 photodiode made by WF. They made a series of four, GP119 to GP122.

I am unsure of the exact date these were introduced, if you have any data on the series, please

WBN went on to manufacture silicon transistors and ultimately integrated circuits. An interesting description of the company can be found in a declassified CIA document dated 19 October 1967, entitled "LEVEL OF TECHNOLOGY AND PRODUCTION OF SEMICONDUCTORS IN THE USSR AND EAST EUROPE". This states:

"East German semiconductor research and development is coordinated by the Institute for Semiconductor Technology of the East German Academy of Sciences at Teltow. Part of the activity of this institute is devoted to acquiring and copying Free World semiconductor devices. East Germany copies and reproduces high frequency transistors that are embargoed by COCOM and imports low frequency general purpose types that are not embargoed. These can be imported at prices below the level of domestic manufacturing costs and are more reliable than domestic transistors.

Tbe East German semiconductor Industry has been built on the basis of Western technology. The main semiconductor plant at Frankfort/Oder, for example, attempted to begin transistor production on the basis of Soviet technology which proved to be faulty and which the East Germans later learned had been abandoned in the USSR. Frankfurt/Oder wns re-equipped by about 1963 with production machinery from the UK (this machinery, purchased at a 50 percent premium, turned out to be obsolete; reject rates on the order of 80 percent were reported). East Germany continues to import some semiconductor manufacturing equipment from the Free World, but is increasingly developing its own because of the difficulties COCOM imposes on procurement from the West".

Of course, the world has changed a lot since that was written. I believe that WBN/HWF/IHT closed in 1990 subsequent to German reunification, but I have no details of this. If you have information of what became of the research institute and manufacturing plant, please

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After collecting all kinds of germanium transistors for more than forty years, I find that the series from some manufacturers somehow appeal more than others. The transistors of the DDR are a particular favourite of mine. If you can help with any of the wanted types shown on my page, or provide original data, please contact me.

Die Germanium-Transistoren der DDR sind ein besonderer Liebling von mir. Wenn Sie mit einem der wollte Arten gezeigt auf meiner Seite helfen kann , oder Originaldaten zur Verfügung stellen , bitte kontaktieren Sie mich .