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Topic # 12374 14-Mar-2007 14:23
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I just need some clarification here.

Are there such things as incompatible phones/faxes?  Or, is it just incompatible wiring.

Now that I have switched my main line to VFX I am currently down from the 4 phones I had to 2 phones as two of my phones don't get a dial tone.  One of the phones is a bog standard Telecom rental phone, and the other phone is a cordless phone.  My fax also doesn't work, but I can keep that on my existing landline.

The two phones that do work are both US sourced phones.  I can place the other two phones on the same cable as the ones that work, and no dial tone.  The cables are all 4 wires.

Also, I have a slew of old phones that came with a PBX that I bought but never installed 15 years ago.  Can I try plugging one of those phones in to my SPA or will I damage something.  I recall reading some prohibition about this before ....

Graham



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  Reply # 63703 14-Mar-2007 14:59
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"Doesn't work" sounds like wiring. What jackpoints, telephone cords etc are you using? The US phone cords have the telephone pair as the center pins in the US plug. The BT plug has line on 2 and 5 ie 1 in from either end. The US style socket on the body of Telecom phones does not neccessarily deliver the line pair to the center pins so cords could be specific to that model phone and you can't mix and match. If you're plugging into a US style socket safer to get a BT-US adapter. Doesn't work well could be the V/I characteristic of the dc feed from your card. PABX phones could be custom build for the PABX possibly digital from the phone itself.



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  Reply # 63704 14-Mar-2007 15:18
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I'm plugging these phones directly into my SPA2102.

And I'm using 4 wire parallel wired cables.

So, are you saying that the two central wires used on my SPA2102 need to be crossed so that they convert to pins 1 and 5 on my BT type phones?



 
 
 
 


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  Reply # 63706 14-Mar-2007 15:42
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No, it's 2 and 5 on the BT plug at the end of the phone cord have to connect to the center pair on the RJ11 US socket.
Something like this will do it. These adapters don't include a capacitor for 3 wire phones.



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  Reply # 63717 14-Mar-2007 16:36
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Ok, I think I'm getting it! 

So, NZ phones have 6 pins, and the ones I need to use are 2 and 5.
And RJ11 cables only have pins 2 - 5, and only pins 3 and 4 are used.

So, I need an RJ11 cable that switches pins 2/3 and 4/5 ?

eg. PT219 from the Pudney catalog?

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  Reply # 63720 14-Mar-2007 17:00
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"So, NZ phones have 6 pins, and the ones I need to use are 2 and 5.
And RJ11 cables only have pins 2 - 5, and only pins 3 and 4 are used.

So, I need an RJ11 cable that switches pins 2/3 and 4/5 ?"

No it's the BT plug on the telephone  that  has 6 pins, the cord probably has only 2 -4 wires depending on ringer wiring.
The cordless phone probably just needs a standard RJ11-RJ11 cord. The other phone may be old enough to be a 3 wire phone. That one probably does have the line pair coming out on the outer pair of the RJ 11 socket on the phone body to make it easier to connect the BT plug at the other end of the cord but that wasn't always the case. Check the original cord.



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  Reply # 63721 14-Mar-2007 17:19
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I'm looking at the sockets (rj11) on my old telecom phone and on the cordless phone.

The cordless phone rj11 socket has 4 metal wires in it.  Connecting a standard rj11 - rj11 4 wire cable to the SPA2102 does not work.

The Telecom phone socket has 6 slots, with metal wires occupying the central 4 slots.  The current cable that does work with my wall socket ( rj11 -> BT ) has 4 wires. 

I am going to ditch the original cables and get new rj11 - rj11 cables for these two phones.

Perhaps I should just get a crimping tool and experiment ...


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  Reply # 63725 14-Mar-2007 18:27
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I'm surprised at the cordless most recent ones are pretty much modified world market. As I've suggested, meter the original cords.

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  Reply # 63758 14-Mar-2007 22:42
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I had an old panasonic cordless that needed the ringer wire and screwy wiring.

Also my swatch twinphone doesnt work on a straight rj to rj cable, it was I think wired straight thru from BT to the rj at the phone, but I tried the cable off an old telecom phone and that didnt work either.




Richard rich.ms



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  Reply # 63902 16-Mar-2007 09:29
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I brought in an old Uniden cordless to see if that would work since my Maxon cordless does not. And yes, plugging it in works fine.

I had 2 other newer Uniden cordless phones with caller id displays at home ( about 3 years old), but both of these have died Cry



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  Reply # 64012 17-Mar-2007 11:37
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Got a meter out and checked the original Maxon cable.  It's straight wired but only 3 wires are connected.  One of the middle wires is not connected.

So, I guess I should try and make a cross over cable using 2 wires only.

My crimping tool arrived yesterday and I now have lots of RJ11 plugs to trial with.


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  Reply # 64041 17-Mar-2007 12:54
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If it has 3 wires, it may need the ringing signal - otherwise it could be an earth but I havent seen a cordless with earth recall since the late 80's.

I would just get a rj11 to bt adaptor and use that with the existing cable. Really they should package one with the linksys to avoid these sorts of problems from happening.  




Richard rich.ms

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