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From: ifjrs@acad3.alaska.edu (STANNARD JOHN R)
Newsgroups: comp.sys.next
Subject: Re: RF on NeXT (was Audio Mixers)
Message-ID: <1991Feb18.100241.6572@ims.alaska.edu>
Date: 18 Feb 91 10:02:41 GMT
References: <10819@pasteur.Berkeley.EDU> <1991Feb13.210116.25168@investor.pgh.pa.us>
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In article <1991Feb13.210116.25168@investor.pgh.pa.us>, rbp@investor.pgh.pa.us (Bob Peirce #305) writes...
>In article <10819@pasteur.Berkeley.EDU> c252-ag@cinna.berkeley.edu (James C. Lee) writes:
>>
>>In <1991Feb5.064037.10135@macc.wisc.edu> Andrew wrote:
>>
>>> Oh, what are people's experience with the amount of RF given off by the
>>> NeXT?  How does it affect TV's and radios?
>>


I'm an Amateur Radio Operator running a packet-radio bulletin
board.  I've got four-to-five radios all running 24 hrs/day, a
phone modem at least turned on most of the time; I'm running the
TNCs (radio modems) on 2 cards in a 386 machine, and sometimes an
external TNC as well.  I also have an answering machine.

This means that (when my NeXT is also on) I have two computers,
two monitors, a phone modem, and usually 5 radios on.  _Once_ in
a while, if the phone modem is turned on but not on-line, I get
a bit of heterodyne on one of the radios.  Other than than, the
only interference I'm getting is from the NeXT PRINTER!

All these machines are within approx. 8 feet or closer--my
tables are in an L-shape.  As a result, when I first bring up
the NeXT, I usually get into Shell and 'su,' then type:
	nppower off
then exit.

This, of course, turns off the printer until I have a need for it,
and does away with any RF getting into my radios (or the other
computer monitor, for instance).  Incidentally, the radios are
all grounded, the computer systems are NOT.  You might want to
try various grounding schemes to avoid any ground-loops.  BTW,
the radios (which transmit at various intervals) have not bothered
the NeXT, either...the only time it did odd things (moved my
cursor around a bit) to the MegaPixel Monitor was when I happened
to have an inadvertant high SWR on one of the radios...when I
adjusted that with a tuner, it stopped affecting my screen.

Hope this helps alleviate any fears of the NeXT putting out any
significant amount of RF (DON'T WORRY ABOUT THE FCC 'A' RATING!
The 'B' rating is in the works, I understand...it just takes some
time!).

John
--

John Stannard
KL7JL@KL7JL	IFJRS@ACAD3.FAI.ALASKA.EDU	BITNET: IFJRS@ALASKA
kl7jl.ampr.org   "God is the Answer!"  "Oh?? ... er, ...What was the Question?"


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