Hi
I've just replaced an original BT extension with a new cable run. The previous extension was made of of lots of old bits of wire with several joints etc. The total run length was about 75 metres and worked perfectly.
I just ran 4 x 80m Cat5e cables using 2 as phone extensions, both buzz!! Any ideas as to why a scrappy old bit of BT wire doesn't buzz and my new shiny twisted pair does?
Ta
Tony
What's going down the other Cat5 cables? Was the old wiring in such close proximity to other cables as the new wiring is?
Do the new cables run alongside mains cables - whereas the old one didn't?
Are you sure that you have used the pairs correctly - and not mixed them, which would defeat their noise-cancelling mechanism.
Roger
I take it you are using three wires You need to use a pair for pins 2&5
If you have used a pair for 2&3, and another wire for 5, it may well buzz!
Sparks...
Maintained the correct pairs and polarity? The line (pins 2 & 5) should be one pair and pins 3 & 4 another.
How did you fix the cable, leg of a staple through insulation?
Long shot, what about the 2 spare pairs in each cable, open or short at each end?
As 2 does nothing whether or not it is put in place is irrelevant (except that it looks untidy if not).
If it has appeared please ignore my previous incorrect statement about 2 doing nothing, it is obviously quite important :-). (Can't even claim it was the effect of cider either).
Another likely cause is if a different phone is used or possibly even relocated. A friend has BT phone (can't recall model) which works fine in all sockets bar one. The fault is nothing to do with the socket but a mains cable near where the phone lead hangs down induces massive hum but on only this one phone. Others used in the same socket are OK.
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