Repair Telephone Connector

[TX-3280]

Hi Everybody,
I have a cool vintage old red telephone.

However, I need to replace the BT431a adapter, (I think this is the correct term). A pic is here:

I have taken the old one off, and I have got 4 multi-coloured wires, I know the order, however, what is the best way to get the copper in to the slots? It seems almost impossible and it is completely infuriating.

Thanks
Dan

[ThePillenwerfer]

Firstly don't strip the inner insulation off as the contacts pierce it.

Strip 10mm of the outer covering off and try to spread the wires 1mm apart. Then feed them into the plug.

When they are right in press down the gold contacts. There are several ways of doing this: with a proper tool, a vice, pliers or hitting them with a hammer. Any of these methods, apart from the proper tool, is unlikely to get the own all the way so you'll have to finish pushing them down with a screw-driver.

I'd test it at that point, but be careful not to pull the wires out, and if all's well use a screw-driver to push the cord clamp down at the back.

There are indeed infuriating and for all that it gets easier with practice it's never a joy.

Good luck

Joe

[Nickthedentist]

It's a plug rather than an adapter

Joe's right, it can be done.

I presume your cable is flat, as opposed to the older, round ones?

Another trick is to prise out the gold contacts with a pin, set them aside, fit the plastic part of the plug to the cable ensuring the coloured wires are visible in the holes vacated by the contacts, and then fit the contacts back in place and push them home.

More tricks here: https://www.vintage-radio.net/forum/...ad.php?t=34066

Good luck, it CAN be done.

Nick.

[TX-3280]

Guys,
I am going nuts.

Do you know the order of the colour wiring just so I know I've got it correct (I did just copy the old one).

I have gone through 3 to 4 plugs now. On the last one all the wires were in and I applied the teeth with pliers, when there was no connection, I pushed the teeth further with a screwdriver.

Absolute nightmare!

[Station X]

Might it not be easier to fit a new cord?

[TX-3280]

Is that easy to do once the phone is opened? It's an old phone.

Cheers

[Nickthedentist]

There are 6 slots, but only the central 4 are generally used.

With the gold contacts uppermost and the springy latch on your right, the "normal" colours are, from left to right:

White, Green, Blue, Red.

HTH,

Nick.

[TX-3280]

Thanks Nick.

Station X.

It is an old phone, would it be easy enough to fit a new cord?

Thanks

[Nickthedentist]

"Old phone" can mean anything from an iPhone 4 to a 1890s wooden contraption with a handle on the side.

Can you be more specific, and give us a picture too, please?

Nick.

[TX-3280]

Hi
It's a BRITISH TELECOM 746F (rotary dial).

Thanks

[Station X]

In that case you can change the cord.

[TX-3280]

Is it easy once the back is opened? I don't want to damage anything.

[ThePillenwerfer]

Very. See this thread: https://www.vintage-radio.net/forum/...d.php?t=108973

To get the top off slacken the screw in the back, though it shouldn't actually come right out, and then lift it up and forwards over the dial.

- Joe

[TX-3280]

Thanks guys, after 5 plugs, I managed to do it with the 5th.

Thanks for the replies.

[Nickthedentist]

Well done!

If it goes again, then change the whole line cord, complete with fitted plug.

Nick.

[julie_m]

You used to be able to buy those plugs in a pack with a simple metal tool which can be hammered or squozen with a vice to push the terminals through the insulation, do the strain relief and leave everything at the proper level. Certainly works out cheaper than the proper crimping tool!

[Dave Moll]

I have always found a vice to be the most effective method, as it can give a controlled amount of pressure - just tighten up until the gap between the plug and the tool fully closes.

[TX-3280]

Cheers again people.