On 1/05/2010 12:07 AM, Invisible wrote:
> I wonder... What's the bandwidth of a punch-card reader/writer?

Good question but I'm afraid I don't know off hand.

Suppose an 80 column card with 10 bits/column.  That is 800 bits per 
card.  Maybe 20 cards per second through a reader ?  Could be higher 
since those things were really impressive bits of engineering.

Something like 16K bps ?

Now cards were not generally used for arbitrary data.  For example in 
many cases cols 73-80 were used for card sequence numbers.  Data was 
often characters so only 6 or 7 bits of variability for most characters. 
  Then the readers have to be fed.

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