[rescue] Creating/Simulating/Emulating an old 1970s Bell Telephone Network

Geoffrey S. Mendelson gsm at mendelson.com
Tue Aug 16 09:53:40 CDT 2005

On Tue, Aug 16, 2005 at 10:08:31AM -0400, Matthew Haas wrote:
> > Also: http://www.mrbill.net/no1ess.pdf
> >
>  I'll check it out. Thanks!
> -Matthew

You  might want to look at ASTERISK, an open source (linux based) PBX.
You can get the cards relatively cheaply, two 4 port FXS (telephone),
eBay clones, cards, two PIII or better X86 PCs and a crossover cable
would give you a nice 8 line, 2 exchange network.

If you wanted to add an outgoing line, a 4 port FXO (exchange) card
is also realtivly cheap, but a $20 (or less) Intel chipset soft voicemodem
will give a single line at the expense of a PCI slot and CPU cycles.

You can add as many as you want until you run out of PCI slots and

If you added a hub and an internet connection, you could use it to call
out with one of the SIP based VoIP providers.

There are "plug and play" instalation CDs (ASTERISK at Home) and tons of

There is one hidden gotcha, the timeout for dialing digits is set in
some versions at about 30 seconds. If you are using POTS phones (as
opposed to SIP or similar phones that buffer dailing) you need to set it
to 3-5 seconds. You can tell if that is the problem if it takes 30 seconds
to dial a number, but the same number ended with a pound sign connects
right away.

It's not as sexyas an old crossbar or Stroeger switch. BTW did you know
that he was an undertaker? I had in the 80's a MackayDymek digital clock
that used them. It had a nixie tube display. You could hear it from the
basement up on my second floor.

Geoffrey S. Mendelson, Jerusalem, Israel gsm at mendelson.com  N3OWJ/4X1GM
IL Voice: (077)-424-1667  IL Fax: 972-2-648-1443 U.S. Voice: 1-215-821-1838 
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