Battery connector

[PaulDevall]

Hi, stupid question but what type of connector is this: ?

Thanks

Looks like a 'stick another wire in it and squash with pliers' type of crimp.

[AC/HL]

Yes, Google "Jelly Crimp"

[Biggles]

Yes, would agree, the good old jelly crimp. Used extensively in the telecom/UG cabling industry. They come in various sizes and there is a proper tool to crimp them. Basically a pair of pliers with on oversize gap so you get a good parallel squeeze on them. Insert two wires fully and squash the crimp flat. They are IDC so no need to strip the wire ends. The jelly inside (hopefully) keeps water out. To remove them without cutting the wire simply crush them with the pliers from the sides until they ping apart. Wear eye protection if doing this as the bits can fly.
Alan.

Ah yes, the jelly crimp used by the millions in BT cabinets, just take a look next time you see one being worked on. You could scrounge a few at the same time (I did but never found a use for them).

[Biggles]

Never without a thousand or two in the van at work. I think they are officially "Connector type 2A". There are also three way versions available, to create a joint with a test point or branch. We don't use them in cabinets, but inside pedcaps and clamp joints, and also inside the good old PJL, post joint, large. The cabinets use Krone 237A's connection strips, which are a lot easier for diagnosing faults as you can break into the pair without having to rip off jelly crimps.
Alan.

[Oldcodger]

I was always amazed that Krones stood up to the damp in cabinets. Jelly cripms- I've always found them in hundreds in BT joints, both internal and external. But problem in external application is that where the wire enters is subject to corrosion, and this is where fault conditions occurr.

[Biggles]

237A's do not always give good service in damp conditions. I have had to replace plenty. On dismantling a failed one they are often coated in green clag and this can eventually cause catastrophic failure of the internal spring contacts. The pairs with no conditions on don't seem as bad, due to the lack of electrolytic action I presume. Bizarrely some last for ages, some don't last very long at all. Some of our cabinets are in exposed locations on high moors on wet soil. They can have both dis faults and leaks. Causes me no end of problems as the fault can appear and disappear depending on wet and dry weather conditions. Even joints made with crimps can fail as sometimes when the installer has nicked the insulation on the pair, over time the damp gets in and corrodes the copper inside causing an invisible fault. A quick tug on the joint can sometimes result in only the insulation holding the connection which of course isn't a connection at all. This often happens right in the neck of the cable. Not the best of things to fix on a lovely wet day. Joint pits full of water don't help either. I could go on...
Alan.

[PaulDevall]

Thanks for the answers, I take it they were not standard on Roberts radios?

[AC/HL]

They wouldn't have been used on any radio natively. Someone has used them to join or extend the original wires from the limited view in that photo.

[Oldcodger]

Originally Posted by Biggles

237A's do not always give good service in damp conditions. I have had to replace plenty. On dismantling a failed one they are often coated in green clag and this can eventually cause catastrophic failure of the internal spring contacts. The pairs with no conditions on don't seem as bad, due to the lack of electrolytic action I presume. Bizarrely some last for ages, some don't last very long at all. Some of our cabinets are in exposed locations on high moors on wet soil. They can have both dis faults and leaks. Causes me no end of problems as the fault can appear and disappear depending on wet and dry weather conditions. Even joints made with crimps can fail as sometimes when the installer has nicked the insulation on the pair, over time the damp gets in and corrodes the copper inside causing an invisible fault. A quick tug on the joint can sometimes result in only the insulation holding the connection which of course isn't a connection at all. This often happens right in the neck of the cable. Not the best of things to fix on a lovely wet day. Joint pits full of water don't help either. I could go on...
Alan.

hence my query on their use in cabinets. I have even found one on a system installation ,hidden under lead flashing on a roof, with layers of tape on top. Surprisingly it seemed in good condition, but not where I'd have placed one.
Alan- that's my experience of "jelly crimps" exposed to the elements. But I'd take you back to the 60's, where installers were taught to take out pairs on aerial cable by slicing into the cable and extracting a pair. I seem to remember the use of self vulcanising tape and plastic tape, but I'd never used this on installations up north, as any cut into an aerial cable would lead rapidly to problems( I think this was banned locally by our man in charge)

[Biggles]

I think we will be accused of hijacking this thread before long! Maybe it's time to start a new thread on the perils of cable distribution. Joints found in strange places? A large clamp joint mid span overhead on a main road. How and why did they do that?
Alan.