The M-3 computer was constructed by members of the Cybernetics Research Group of the Hungarian Academy of Sciences (Hung: Magyar Tudományos Akadémia Kibernetikai Kutató Csoportja, abbr. MTA KKCs) from mid 1957 until the beginning 1959. I was a member of MTA KKCs until 1967. The Group was established for the sole purpose of constructing the first Hungarian electronic tube computer, first the B-1, then the M-3, which began the age of computers in Hungary. We received the basic design of the M-3 computer - mid 1957 - from the Soviet Union, but we received the necessary parts (vaves, cuprox diodes, connectors etc.), too, we used only resisitors and capacitors from a Hungarian plant REMIX. The whole mechanical and electronical consrtruction (logical unites, casing, drum etc.) was done by our mechanical engineers and our mechanical and electronical workshop.