Running ethernet and PSTN down a single CAT5

NathanE

NathanE

NathanE

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Wanting to sign up to Sky+ but can't yet because I don't have a phone port anywhere near where the Sky box will go.

I do however have a Cat5 that emerges from the wall in the perfect spot.

I seem to recall that 100Mbit Ethernet only actually uses 4 wires of the 8 available in a Cat5 cable. So this leaves 4 wires that aren't be used at all.

Could I use 2 of these unused wires and wire up a PSTN line?

Would there be interference issues? Bare in mind it's only going to be used for Sky+.

PS: I'm aware that this would restrict me from running Gigabit over the cable in the future.
 
You can pay I think its 25 quid one off and you dont need to have a phone line, not the answer to your question sorry just an alternative. of course to order a box office you would need to phone sky box office.
 
I think that you'd probably be ok, its twisted pair afterall so interference should be ok. The line is vary rarely used anyway, to my knowledge.
You can but give it a go, just recrimp rj45 back on if it somehow goes **** up.

I have successfully run 2x10/100 down one cat5e before and it was fine.
 
If it's wired to standard, only the green and orange pairs will be used for 10/100. So pick either blue or brown to use for the phone line.

You could either rewire the socket or make some sort of custom cable.
 
Neat.

I will have to find a RJ45 & RJ11 combined wall plate to put behind the TV area. That will save me from doing some dodgy bodge where a little RJ11 cable is just dangling there with no outer sheeve :p

The opposite end isn't a problem as that goes to a patch panel anyway.
 
NathanE said:
Neat.

I will have to find a RJ45 & RJ11 combined wall plate to put behind the TV area. That will save me from doing some dodgy bodge where a little RJ11 cable is just dangling there with no outer sheeve :p

The opposite end isn't a problem as that goes to a patch panel anyway.
Click to expand...

A dual RJ45 wall plate might work.
With a little encouragment I think an RJ11 plug will fit and lock into an RJ45 socket.
 
You do realise you only need the phone line for the install...

The engineer just used an extension for five minutes, then it hasn't been connected since (9 months ago).
 
You do realise you only need the phone line for the install...
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dont even need it for that......

mine was installed with no line at all...It just means a two miniute phone call for the installers to kode the card with the box. thats on SKYHD





bullit
 
RJ11 fits in RJ45 fine. I use it for digital and analogue phone extensions all the time. You can buy little CAt5 Splitter dongles. They're probably cheaper and easier than re-wiring the faceplates though at the sacrafice of looking pretty. (though some can be screwed to skirting)

Edit: make sure you wire it up and then double, tripple check it before you pug something into it. PSTN runs at 48-50volts which is plenty to damage a NIC if connected inadvertently to the tx or rx pins.
 
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Skidilliplop said:
RJ11 fits in RJ45 fine. I use it for digital and analogue phone extensions all the time. You can buy little CAt5 Splitter dongles. They're probably cheaper and easier than re-wiring the faceplates though at the sacrafice of looking pretty. (though some can be screwed to skirting)

Edit: make sure you wire it up and then double, tripple check it before you pug something into it. PSTN runs at 48-50volts which is plenty to damage a NIC if connected inadvertently to the tx or rx pins.
Click to expand...

Was about to suggest a dongle, saves messing around :)
 
I got it to work.

In the end I just put a BT socket on the wall next to the existing Ethernet socket and daisy chained it using a short piece of CAT5 and some electrical junction blocks. Not the prettiest of the solutions but it cost me £0 and it's all hidden behind the TV anyway.

The opposite end was fine as I have a patch panel there which makes this sort of thing easy.
 
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