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Morris Dovey
 
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Ba r r y (in ) said:

| On Sat, 3 Sep 2005 00:58:49 -0500, "Morris Dovey"
| wrote:
|
|| Or is it only this quick and easy for amateurs?
|
| Cell sites aren't repeaters. Repeaters are simple.
|
| As you know, repeaters take a signal in, and retransmit it. Cell
| sites connect cellular phones via radio to the rest of the world.
|
| Cell sites are connected back to a switch, usually via a T1, DS3, or
| some sort of optical link. The site needs to be built in the switch
| database, and the switch needs to know about the adjacent cells.
| The site also needs quite a bit more commercial power than a ham
| repeater.
|
| The difficult part is providing enough bandwidth back to the switch,
| and the fact that all of the central offices, possibly including the
| cellular switch in the area, are down, and all the cables are
| submerged.
|
| Non-telco cell companies depend on the local telco to get site
| signals back to the public telephone network. Also, most towers
| are now collocated. Lose a tower, lose all of the brands on it in
| that area.

Yuppers - I understand the difference in circuit complexities.

As a first response measure, an isolated (independent) cell that
connects all calls to an EOC "help desk" would be a major improvement
over no communications at all in the initial period following a
disaster. Full-feature operation for health and welfare traffic can
wait a bit longer than a family trapped in their attic by rising
floodwater.

FEMA maintains multi-mode/multi-channel communications centers in at
least state capitols (I was the volunteer operator for the one in Des
Moines during our '93 flood) that are capable of providing the initial
essential disaster communications with the outside world. These, too,
are more complex than most ham stations but were pre-packaged in a
single rack unit that could be relocated by truck or helicopter - and
even operated by people without equipment-specific training.

A ham repeater doesn't require (isn't allowed) much power and most
that I've seen used 12V auto/truck batteries for immediate backup -
does a cell site require more than the 2-5kW available from a small
portable generator?

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/solar.html