Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!bellcore!texbell!vector!telecom-gateway
From: sysop@pinn.uucp
Newsgroups: comp.dcom.telecom
Subject: Re: Prefix '520' For Los Angeles Radio Stations
Message-ID: 
Date: 28 Sep 89 01:03:37 GMT
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X-TELECOM-Digest: volume 9, issue 416, message 6 of 6

I read several messages about radio station's toll free phone lines
and I have some comments to add to the discussion.

I have lived here in South Florida for about 7 years now and have been
involved in broadcasting since I moved here.  I used to be chief engineer of
a TV station down here and at the time we had some audience participation
shows on the air.  This same discussion holds true for radio stations in the
area.

This area has always been known for its telephone contesting.  That is,
people are told to be the thus and such caller and they win something.
This had caused exchange overload in a very highly concentrated area.
Normally the phone company would have said too bad, but since there are
several military establishments that feed off some of these key COs,
something had to be done.  I don't know if this has been done in other parts
of the country, but ALL radio stations and TV stations that do any kind of
phone contesting have special lines installed here.  All lines are part of the
550 exchange from South Miami through to West Palm Beach.  These are called
"choke exchanges."  As far as the caller in concerned, there is only one
number to call, beginning with 550.  In each exchange area, this 550 number is
translated into a local exchange number and then FXed back to the station.
If memory serves, we actually had 4 different sets of FX lines.  They were
Miami, Ft. Lauderdale, Deerfield and Palm Beach.  We paid plenty for them!
What was interesting was these lines were specially translated at each CO
point, but were ordinary FX lines for outgoing purposes.  I had them wired
up to our PABX so that I could make calls to any of these areas.

The reason they are called "choke exchanges" is that to prevent CO lockup,
only two calls from each exchange are allowed to go inter CO.  The rest of
the calls get a local exchange reorder.  Hence, the exchange chokes off the
calls before they can cause network overload.  In theory, its a good idea,
but in practice there are problems.  Since only two calls from each exchange
are allowed into the inter exchange network, if there are two stations
carrying on a contest at the same time, everyone trying to get into one
stations contest may block all calls from getting into the other stations
contest.

I hope you found this interesting.

Andy

{your favorite gateway}!codas!novavax!pinn!sysop

[Moderator's Note: Welcome to the Digest, Andy, and I hope you will become
a regular contributor.  PT]