UKNC

UKNC () was a Soviet PDP-11-compatible educational micro computer, aimed at teaching school informatics courses. It is also known as Elektronika MS-0511. UKNC stands for Educational Computer by Scientific Centre.
Hardware.
One unique part of the design is the usage of a peripheral processing unit (PPU). PPU unloaded the CPU, taking responsibility for the management of peripheral devices (display, audio, and so on), but could run any user programs, as well as CPU.
The computer was released in 3 sub-models: 0511, 0511.1, 0511.2. The 0511.1 model, intended for home use, had a power supply for 220 V AC, while others used 42 V AC. The 0511.2 featured new firmware with extended functionality and changed the marking of the keyboard's gray keys, compared to the initial version. The photo shows an 0511.2 variant.
There was no active cooling, and at least the 0511.2 variant tended to overheat and halt after several hours of operation.
The design of the case, the layout of the keyboard, the location and the shape of expansion slots were inspired by the Yamaha MSX system, which was purchased by the Soviet Union in the early 1980s for use in schools. The same case, with changed markings, was re-used to produce an IBM PC clone called Elektronika MS-1502, though it less well-known than the once famous Poisk computer. The same case and keyboard were later used to produce yet another educational computer called Rusich (i8085 based).