** Reply to message from "Leon D. Zetekoff"
<os2-wireless_users@2rosenthals.com> on Sun, 10 Feb 2008 08:30:02 -0500
> Hi Mark...I wouldn't use coax for telco. The impedance is one issue.
> Phone wire is usually a twisted pair. I'd pickup one of the multiple
> wireless phone gizmos. I rent here and I use cordless phones where there
> is no premise wiring. The new DECT cordless phones are on a different
> frequency than 900/2.4/5.8 so there shouldn't be any interference, etc.
Mark brings up the real problem with what you want to do - that twisted pair
part of it. Phone lines (and ethernet) are used as a differential pair in what
started as the standard 20 ma current loop mode. This provides for common mode
noise rejection and low impedance current paths. Coax is designed as a
shielded single wire - the shield is NOT part of the signal carrying circuit.
At phone line frequencies (ignoring ADSL) the signal rates are, at least in
theory, band limited to 4khz so this should not make a difference but the
current loop characteristics present a different problem. Don't forgrt that
the analog ring tone is a 20 hz, 90-135 volt signal. Unless the cable is part
of the rental unit, I would suggest a few bucks for a run of Cat5 wire - use
the cable to pull the cat5 if it's not stapled down inside the walls. I just
ran Cat5 all over the house to replace the kludge the phone company put in 40
years ago and a couple of packs of RJ45/RJ11 jacks and plugs is cheap. Most
home inprovement places also carry cheap tools to install the connectors.
That said, I think Leon has the best suggestion: go wireless unless you intend
to conduct NSA level classified business over the phone. I saw a 4-unit setup
at Sam's the other day for something like $40 including an answering machine
and intercom features. The mobility will be a wife pleaser, I can assure you.
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