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[TableLeg]

I just bought a new phone, and found that the supplied Phone cable (which has a RJ11 on one end and another Rj11 on the other with an RJ11 to BT phone plug adaptor) worked fine but was too short for I wanted to run the cable.

Therefore I thought I would use one of the various other BT/RJ11 cables I had lying around and found that none of them would work.

A close look seems to show that the cable supplied with the phone has 2 pins (in the middle of the row on the RJ100 plug) whereas all the other cables have 4 pins.

I can only presume that they are wired up differently. So how would I go about sourcing a longer replacement cable?

Does anybody understand what is going on here?

[TableLeg]

Having now searched the net I wonder if the cable is what appears to be known as a 2 wire RJ11 to BT crossover cable?

The RJ11 end has only 2 pins, both terminate in the middle of the 6 pin slots. Looking at the connector towards the pins, the righthand pin wire colour is green and the lefthand one red.

On the Bt plug end, both centre pins are terminated but the wiring colours are reversed i.e. The righthand pin is wire colour red and the lefthand one green.

Is my assumption right?

[TableLeg]

Oh and another thing..........

As already mentioned, the cable supplied with my phone has RJ11 plugs on both ends and came with an RJ11 to BT plug adaptor.

Could it be possible that the adaptor switches the 2 pins over so that once the BT plug is connected it effectively becomes a straight through cable as opposed to a crossover?

I suspect i'll have to do a continuity test to be certain.

[HPsauce]

Hello Tableleg,
It won't be a crossover issue, polarity is largely irrelevant in phone systems.

It almost certainly will be a "which pair?" issue.

BT phone plugs have 6 connectors (not all used or present) and the main "active" ones are 2 and 5.
As they are numbered 1 to 6 these are NOT the central pair.

If your RJ11 cable (and hence also the phone) uses the central pair then the adapter is realigning those (if it works with it).

This is a common problem with modem cables, where many (most?) US-designed modems use the central adjacent pair of connectors.
A typical UK modem cable (I'm looking at one now) will use the central 2 (of 4) connectors at the RJ11 end connected to numbers 2 and 5 (of 6) at the BT plug end.

[waltergmw]

Hi TableLeg,

I suggest the simple solution is to buy a longer RJ11 cable from somewhere such as:-

http://www.adslnation.com/phpapps/catalog/index.php?cPath=21&osCsid=cm05v71djvucdekopfp4gp8d94

Kind regards,
Walter

[TableLeg]

Thanks guys 

If I understand you right, the cable uses the middle pair on the RJ11 but the adaptor then routes the middle pair to pins 2 and 5 on the bt adaptor.

If this is correct, how would I go about getting new cables?

I would need to ensure that the RJ11 had the same middle pins connected and that the BT end (preferably without an adaptor) was to pins 2 and 5.

Do you need special tools to make the connections yourself? I wonder if DIY would be my only option.

[TableLeg]

Or can I just get another one of the adaptors that was supplied???

If so, any idea where could I find one?

[HPsauce]

How long and tidy do you need this to be?

Solution 1: as per Waltergmw
Solution 2: telephone extension lead
Solution 3: modem-type cable, but they're mostly under 2m long.
Solution 4: Move your phone socket

[TableLeg]

Now thinking about it, I believe that all I would need is a Bt plug to BT Plug lead. If such a thing exists.

As the device to which the phone is connected has a bt plug input from the master socket and also a bt plug output.

With the phone lead and adaptor ming the normal 2+5 pins on the bt adaptor, I would only then need a lead which also connects pins 2+5 to the master socket.

I think im right. But....a quick search doesn't seem to show any BT plug to BT Plug cables.

Any idea's other than making one?

I really want to minimize the number of connections.

[HPsauce]

None of that makes any sense, what are you not telling us? 

[TableLeg]

Sorry, yes I should have explained this better 

I just bought a Belkin surge protector, and it has a BT plug socket input and 2x BT plug outputs.

I want to use this so therefore realised that I needed a cable with a BT plug on it to connect to the surge protector.

But as the input is a BT plug socket, this would be connected to the master socker which is also a BT plug socket.

So I would need to find a way to connect the 2 together.

Having the phone connected to one of the outputs I now see would be fine as the adaptor makes the 2x middle wires go to pins 2+5 on the BT plug.

I hope this makes a bit more sense.

If not, i'll knock up a quick diagram to explain it better.

[HPsauce]

1. Ask Belkin how it's supposed to connect
2. Don't use it on broadband

Sounds like "carp" design to me, or are you misreading the manual?
(I've never seen a BT to BT cable)

[TableLeg]

[HPsauce]

It's still carp, picture or no picture, makes no difference.

If Belkin don't provide a lead to connect it to your BT socket it's "NOT FIT FOR PURPOSE".  
Send it back to the retailer for a refund.

PS I refer to my earlier post - RTFM! 
(all the ones I've seen have RJ11 phone input)

So long and thanks for all the fish.