Engineer Reverse-Engineered Apple II Behind Iron Curtain in 1979
Original: A communist Apple II and fourteen years of not knowing what you're testing
Why This Matters
Demonstrates how reverse engineering enabled technology transfer across political barriers during Cold War era
Bulgarian engineer Ivan Marangozov at the Institute of Technical Cybernetics and Robotics in Sofia created the IMKO-1 in 1979, an identical clone of the Apple II with same ROM, schematics, and 6502 CPU running at 1 MHz, marking the first Bulgarian personal computer.
The IMKO-1 was a complete Apple II clone with identical ROM and schematics, featuring a 6502 CPU running at 1 MHz. Key differences included a heavy metal case, linear power supply, and replacement of lowercase Latin with uppercase Cyrillic characters. The keyboard used 7-bit character codes, causing Cyrillic to overlap with Latin lowercase. This engineering decision meant users could only access one alphabet at a time. The machine later evolved into the Pravetz series computers that became widespread in Bulgarian schools during the 1980s. The reverse engineering reportedly involved Bulgarian intelligence services procuring Apple II systems from Western sources, though the exact methods remain unclear.