Archiving Data Permanently

[Markku Kolkka]

Fritz Whittington kirjoitti viestissään (lähetysaika torstai, 25. 
elokuuta 2005 01:26):
> In 1977,
> I designed and built a gadget that read paper tape a lot
> faster than the Teletype could, and I'm a software engineer,
> not a hardware designer!   What makes paper tape so easy is
> that the sprocket hole gives you a positive indication that a
> set of holes is ready to be sensed at a fairly precise offset
> distance away.  Nine teeny light sensors mounted in the proper
> pattern, and nine input bits on the computer to read them. 
> Didn't matter if you pulled the tape through at any particular
> speed (as long as it wasn't too fast for the computer
> software).

So, you re-invented the method used by the British Colossus 
code-breaking machine. 
http://www.codesandciphers.org.uk/lorenz/rebuild.htm
The Colossus actually used the sprocket hole signal as its system 
clock.

-- 
 Markku Kolkka
 markku.kolkka at iki.fi