[aprssig] 8 hour Backup Power Rule

Corey Shields cshields at indiana.edu
Tue Mar 18 08:51:57 EDT 2008

Steve Noskowicz wrote:
>    NOTE:, these systems will be useless well before the 8 hours is up - pretty
> much immediately, because they will be overloaded.  The user-to-channel ratio
> is somewhere around 50 in the systems I was familiar with [it's called
> trunking], so only 1/50 or only 2&% of the users can get service in an
> emergency.  At Northern Illinois University during the Feb shootings, many
> students couldn't get service for quite a while to let their parents know they
> were ok.
> 73, Steve

I second this, and I also think that the general public is starting to 
learn this as well but there isn't much they are willing to do about 
it.  I was in San Jose CA in late October when the ground started to 
shake (the 5.6 Alum Rock quake).  My first instinct wasn't to get away 
from the mirrors hung above my head (stupid) but to grab the cell phone 
and call my wife before the circuits were jammed.  I had the phone 
dialing before the shaking stop. After that first call I couldn't get 
through to anyone for more than an hour, and it ended up being just a 
moderate quake.

As for University areas, this problem is a bit compounded.  Many 
students these days are turning down land line plans offered by their 
residence halls in lieu of just a cell phone.  This trend is so bad in 
some schools that land line offerings are being halted altogether..

Of course, even with a land line, think of all of the people who have 
only a cordless phone requiring electricity.  :)

-Corey (KB9JHU)
Corey Shields
High Performance Systems, Indiana University - UITS

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