The core of this computer comes from MINSK’s mainframe systems. Known for their durability, these systems included clones of the Intel 8086 processor, a product of the semiconductor industry in the 1980s. Only a limited number of approximately 80,000 EC-1841 mainframes were produced, and some of these continued to operate well into the 1990s.

A special feature of this particular restoration was the discovery that the processor on the processor board used in the “Chernobyl Family” computer was a military version of the ES-1841 processor, known as ES-1845 and frequently used by the KGB. that period.

With a clock speed of around 5 MHz, these processors were not suitable for games or complex computing tasks of the time, but were capable of running a cloned Soviet version of DOS called alphaDOS with a high level of translation.

The main challenge was finding the software for this project, as it was not easy to find special floppy disks compatible with this old technology. Finding these relics of the past has been complicated by the rarity of five-inch floppy disks, especially those produced by the Kiev Electron Mass Factor plant, which are virtually unavailable today. These disks were required for the operation of the main computer in a specially designed chassis.

Computer in the Chernobyl exclusion zone restored and started / Photo Chernobyl Family

The mainframe design had built-in modules that allowed separate computing cards to be placed in two mainframe modules. These cards were equipped with their own power subsystems and could be connected together to access different computing solutions.

The seven empty slots in the restored computer are occupied by five processor cards, including one clone of the Intel 8086 processor, a graphics processor, a card for COM ports with a quad-trigger mouse controller, and two RAM cards.

While the larger RAM card can store 512 kilobytes of information, the smaller one has a capacity of only 128 kilobytes. In today’s context, this is roughly equivalent to the amount of memory of a website icon.

One of the challenges in restoring old technology was the need to reconfigure communications system (COM) cables and ports used in 1980s-era computers. The absence of COM cables due to the non-standard nature of drivers and electrical designs of the period would require a redesign of the entire communications and hardware system.

Fortunately, this wasn’t necessary to connect the Electronica MS-6105 12-inch cathode ray tube (CRT) monitor used for graphics output.

Restoration and rescue of a computer from Chernobyl: watch the video