Path: utzoo!mnetor!uunet!lll-winken!lll-tis!ames!ncar!noao!arizona!naucse!kds
From: kds@naucse.UUCP (Kevin Strietzel)
Newsgroups: comp.arch
Subject: Re: Computer noises (was Re: Cray architecture)
Message-ID: <630@naucse.UUCP>
Date: 4 Apr 88 18:38:42 GMT
References: <7762@alice.UUCP> <5029@nsc.nsc.com> <850@gethen.UUCP>
Organization: Northern Arizona University, Flagstaff, AZ
Lines: 25
Summary: Lineprinter Music

In article <850@gethen.UUCP>, farren@gethen.UUCP (Michael J. Farren) writes:
>In article <5029@nsc.nsc.com> curry@nsc.UUCP (Ray Curry) writes:
>>I'll tell you how old I am.  When I started college, they were ripping out the
>>vacuum tube IBM 7xx.
>My three fave computer noise stories:
>I.  The line printers used with some earlier IBM systems had (as many
>still do) bands of type which continuously rotated, with hammers that
>were fired when the appropriate letter came by.  By selecting the output
>carefully, you could get the hammers to fire at a fixed frequency, and
>by varying the output you could change this frequency.

I think this was done.  I remember hearing about it a *long* time ago from a
reliable source.  Knowing him, he'd probably tried it.

More recently I tried this on an old Oki 82 matrix printer.  It wasn't very
successful, but got some interesting results.  It was hard to find particular
characters that fired the print wires at the right frequency!

And yes, chain, train and band printers are still made by lots of companies.
The fastest I remember hearing about is 2200 lines/minute.

-- 
+------------------------------------------------------------------------------+
| Kevin (So What If I'm Just a Student) Strietzel			       |
| {... | allegra | ihnp4 | ...}!arizona!naucse!kds		               |
| "It's easy to pass the buck - especially to someone who wants it!"  -- me    |