Path: utzoo!mnetor!uunet!pyrdc!grebyn!umd5!davidc
From: davidc@umd5.umd.edu (David Conrad)
Newsgroups: comp.arch
Subject: Re: Computer noises (was Re: Cray architecture)
Message-ID: <2516@umd5.umd.edu>
Date: 30 Mar 88 02:19:53 GMT
References: <769@kaos.UUCP>
Organization: University of Maryland, College Park
Lines: 23

From article <769@kaos.UUCP>, by romkey@kaos.UUCP (John Romkey):
> In article <25959@yale-celray.yale.UUCP> lisper-bjorn@CS.YALE.EDU
>>Some historic computer trivia: the Swedish late-fifties computer BESK at
>> ...
>>it compute. A skilled operator could actually hear if the computer had got
>>stuck in an infinite loop!
> The Radio Shack TRS-80 Model 1 (a personal computer before PC meant
> IBM) put out enough RF interference that it became popular among
> TRS-80 hackers to put a small radio next to the machine to listen to
> what it was doing. Some people tried to program them to play music
> this way...

I read an article in some PC magazine (PC maybe) that described the correct
frequencies to listen to your AT.  The article claimed that it was fairly
easy to hear an infinite loop.

As an aside, netwatch, as distributed by IBM as part of their TCP/IP on the
PC software has a noise option ('N') which makes a noise whenever a packet 
goes by.

> 			- john romkey

-drc