Reading Soviet Semiconductors

 You might encounter a few Soviet semiconductors if you find an old Soviet produced electronic device that is not working and was disassembled. Finding the specification for this component on the internet would be very hard because those parts have not been produced since beginning of 1992.

However, there are a number of links on the internet that teach you how to read semiconductors produced in the Soviet Union.

1. Reading the Text

You do not need to know Russian or use Google translate to read the text. Having access to a Russian keyboard would be an advantage. You can add https://narod.ru to the Google search because a number of https://narod.ru personal websites might have a list of old Soviet specifications not only for transistors but valves a well.

I found the following useful information in this useful link (https://www.wylie.org.uk/technology/semics/Soviets/Soviets.htm):

"

As you might expect, the very earliest types were idiosyncratic; I mention them below.

Devices introduced from 1959 to 1963 conform to State Standard 5461-59.

The earliest of these have an initial П (Latin P) for transistors or Д (Latin D) for diodes.

This is followed by a number belonging to defined groups.

For transistors:

1 - 100 low-power germanium low-frequency

101 - 200 low-power silicon low-frequency

201 - 300 power germanium low-frequency

301 - 400 power silicon low-frequency

401 - 500 low-power germanium high-frequency

501 - 600 low-power silicon high-frequency

601 - 700 power germanium high-frequency

701 - 800 power silicon high-frequency

For diodes:

1 - 100 point-contact germanium

101 - 200 point-contact silicon

201 - 300 junction silicon

301 - 400 junction germanium

401 - 500 mixer microwave

501 - 600 multiplier

601 - 700 video detector

701 - 749 parametric germanium

750 - 800 parametric silicon

801 - 900 stabilitrons

901 - 950 varicaps

951 - 1000 tunnel diodes

1001 - 1100 rectifier columns

This may be followed by an optional letter denoting the development variant, following the order of the Russian alphabet (А,Б,В,Г, etc.).

A few have one or two specialised trailing letters.

A number of members of the П series of transistors were enhanced and renamed the МП varieties, which means 'modernised P'. This prefix was given to devices that were the result of improvements of the old transistors from the П series. Usually this meant replacing a hot-rolled package by a cold-welded one. So МП102 is electrically equivalent to the older П102 (it has the same crystal) but in a new package. With a few odd exceptions, this only applies to low-numbered types that originally used a small 'top hat' style of package. The МП series went on to include types for which there is no П-series predecessor.

My interest primarily lies with the above types, and I will not show many later ones.

Devices introduced from 1964 to 1973 conform to State Standard 10862-64 (although some of the older types continued to be made, particularly those in the modernised outline):

An initial letter or digit indicating the semiconductor material: Г (latin G) or 1 for germanium, K or 2 for silicon, and A or 3 for gallium arsenide. The digit versions have higher temperature tolerance; a correspondent has told me that this means that they were intended for military use.

A second letter designating the type of device: Д (Latin D) for diodes, Т for transistors, В (Latin V) for varicaps, А for microwave diodes, Ф (Latin F) for photo-devices, Н (latin N) for uncontrolled multilayer switching devices (dynistors), У (latin U) for controlled multilayer switching devices (thyristors), Й (Latin I) for tunnel diodes, С (latin S) for stabilitrons, Ц (latin Ts) for rectifier columns and units.

These are followed by a number designating the purpose or electrical properties of the semiconductor device. As with the older standard, the numbers are grouped into ranges with defined categories: I list them further down.

Lastly there is always a letter denoting the development variant, following the order of the Russian alphabet (А,Б,В,Г, etc.).

Devices introduced from 1974 conform to State Standard 10862-74, but the "Translations..." document does not describe this. It is clearly an update to 10862-64.

"

2. Reading Pins

You can follow this diagram to identify the pins of a Soviet bipolar junction transistor (BJT):

I worked out this diagram through internet research and component testing for a few Soviet transistors that I had access to. However, you still have to be careful because the standards might have been modified towards the end of 20 century. You need to connect two 1 kohm resistors to at least two of the transistor pins to ensure that you do not burn the transistor because the base emitter voltage must be under 0.7 volts.

Click on this link for more information: https://en.wikipedia.org/wiki/KT315