I moved into a new house and have new voip phone service via the local cable
company. The way it's configured is the cable from outside goes into the
modem, model number Arris TM502G, then the output of the modem, labeled Tel
1/2 goes into a telephone line splitter, then the single ended part of that
splitter, goes into a telephone wall jack which is supposed to feed the rest
of the house. The third connection of the splitter goes to my Uniden
portable phone system, model EXAI3428, which I will call system #1. It works
fine.

To avoid confusion with another Uniden system, a model EXAI5688-3, I'll call
that system #2. I want to hook up system #2 at a different wall jack in
another room. When I did, there was no dial tone. System #2 was working last
week in another home so I am fairly certain that it was ok. I have a
telephone line polarity checker probably better known as, "The Fox," made by
Triplett Corporation. The l.e.d. lights up when I plug it into the back of
the modem. When I remove the telephone line from system #1 and plug in the
Fox into the splitter, it doesn't light up. I disassembled the wall jack and
sure enough, if I hook up the red test lead to the green wire and vice-versa
for the green test lead, the l.e.d. lights up. Question 1, does it make
sense that system #1 can work if the polarity is reversed? I removed the Fox
and plugged system #2 in the same jack. System #2 didn't work. Then I
reversed the red and green wires in the wall jack and tried system #2 in the
wall jack in the other room. Still no dial tone. So I disassembled the wires
in that wall jack. The wires were so snug that I could only pull it out from
the wall about 1 inch. I looked behind the jack and saw that the phone wires
were the old style red, green, yellow, black wiring. When I reversed the
wires in the wall jack back in the room where system #1 was, I noticed the
wires were a white/blue pair. I then plugged the Fox into a jack in a third
room. The Fox lit up. I plugged in system #2 into the third room and got a
dial tone. Question #2, is there a way to get the red and green wires in the
wall jack that isn't working tied into the blue/white pair at the outside
box? And finally, why does the telephone line splitter reverse the polarity?
I tried another splitter and it did the same thing.

Thanks for your reply.
--
David Farber
Los Osos, CA