From: greg@ideath.goldenbear.com (Greg Broiles)
Date: Sun, 15 Aug 93 00:41:52 PDT
To: cypherpunks@toad.com
Subject: Pagers
Message-ID: <m1aB9B1w164w@ideath.goldenbear.com>
MIME-Version: 1.0
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For what it's worth, my pager (a Motorola Bravo (Plus?) using a frequency of 
152.240 MHz) cheerfully receives pages while inside my microwave. (No, I 
didn't turn the microwave on. :) What that implies about the shielding 
capabilites of my microwave (and the safety of its continued use) is beyond 
my knowledge of RF and microwaves. I have some idea (please correct me if 
I'm wrong here) that shielding effective for energy at one frequency (like 
that of my pager) may be ineffective or less effective at another (like the 
frequency of microwaves).

I'm intrigued (and alarmed) at the idea that it's possible to disable pagers 
via remote control. While I'll admit that there's some wee utility in being 
able to make sure nobody can use my pager if it's lost/stolen, it's 
sounding, from the posts to the list, like it'd be possible to disable many 
folks' pagers, were some miscreant so inclined. I know of pagers being used 
by police, fire department, search & rescue, private/campus security, and 
medical folks; if someone put some time into the "kill all the pagers" 
thing, it could be pretty damaging.

Then again, knowing that, if I swiped somebody's pager, I'd probably just 
remove the battery for a few days, and hopefully miss the "stop working now" 
signal.

I'm curious, though, how long the battery would last - my pager has a single 
AA battery, which lasts about a month. On average, a pager in the "find this 
pager" mode would have a single half-discharged AA battery to power its 
transmitter; and that transmitter would be sending its signal without 
benefit of any sort of external antenna. My very limited knowledge of RF 
propagation makes me think it'd be hard to get much range or duration under 
those circumstances.

I'd be interested to see this thread move over to comp.dcom.telecom - there 
might be more folks who know about pagers who could comment. This is 
interesting, but frankly I'm still pretty skeptical. 


--
Greg Broiles                            greg@goldenbear.com
Golden Bear Computer Consulting         +1 503 342 7982
Box 12005 Eugene OR 97440               BBS: +1 503 687 7764