On Sat, 26 Sep 2020, Rudi Blom wrote:
"Researchers will be able to gain a deeper
understanding of what’s
considered the world’s oldest surviving (digital) computer after its
long-lost user manual was unearthed. The Z4, which was built in 1945,
runs on tape, takes up most of a room and needs several people to
operate it. The machine now takes residence at the Deutsches Museum in
Munich, but it hasn’t been used in quite some time."
https://www.engadget.com/oldest-computer-manual-zuse-z4-161214346.html
Which reminds me of the Z3; from Wikipedia:
``The Z3 was a German electromechanical computer designed by Konrad
Zuse in 1935, and completed in 1941. It was the world's first working
programmable, fully automatic digital computer. The Z3 was built
with 2,600 relays, implementing a 22-bit word length that operated
at a clock frequency of about 4–5 Hz. Program code was stored on
punched film. Initial values were entered manually.
The Z3 was completed in Berlin in 1941. It was not considered vital,
so it was never put into everyday operation. Based on the work of
Hans Georg Küssner (cf. Küssner effect) e.g. a "Program to Compute
a Complex Matrix" was written and used to solve wing flutter problems.
Zuse asked the German government for funding to replace the relays
with fully electronic switches, but funding was denied during World
War II since such development was deemed "not war-important".
The original Z3 was destroyed on 21 December 1943 during an Allied
bombardment of Berlin. That Z3 was originally called V3 (Versuchsmodell
3 or Experimental Model 3) but was renamed so that it would not to
be confused with Germany's V-weapons. A fully functioning replica
was built in 1961 by Zuse's company, Zuse KG, which is now on
permanent display at Deutsches Museum in Munich.
The Z3 was demonstrated in 1998 to be, in principle, Turing-complete.
However, because it lacked conditional branching, the Z3 only meets
this definition by speculatively computing all possible outcomes
of a calculation.
Thanks to this machine and its predecessors, Konrad Zuse has often
been suggested as the inventor of the computer.''
-- Dave