Germanium transistors from the former USSR are cheap, generally high quality, available in large quantities and very cheap compared to their European counterparts.
They are their own thing and are not direct copies of European transistors – you can find similar transistors, but they are never like-for-like replacements. They nearly always sound different and have their own character. So when sellers on eBay compare the Soviet version to a western one, just use this as a rough guide.
Note:
- Check pinouts, as B, C, E is common
- The emitter is often marked with a dot on the case
- The case is sometimes connected to the base
- hfe on most datasheets will be on the high side, due to high test currents. Look at the minimum gain as a more likely average than the maximum
- They tend to be low leakage compared to European transistors, which means that many will not work in circuits that require high leakage to self-bias