Kitz Forum

Broadband Related => Broadband Technology => Topic started by: CrazyTeeka on August 25, 2015, 10:22:28 PM

Title: Silver Drop Cable
Post by: CrazyTeeka on August 25, 2015, 10:22:28 PM
If OR could install silver pair cable from NTE to DP to FTTC cab, what kind of difference would it make in theory?
Title: Re: Silver Drop Cable
Post by: NewtronStar on August 25, 2015, 10:38:20 PM
If OR introduced silver into the pairs you woud find by the next morning your drop cable cable had disappeared due to criminality it still happens with copper lines  :o
Title: Re: Silver Drop Cable
Post by: Weaver on August 25, 2015, 11:10:23 PM
Since the conductivity of silver is only about 6% better than copper, I can't see that it would make much difference.
Title: Re: Silver Drop Cable
Post by: Weaver on August 25, 2015, 11:15:37 PM
The difference comes out at roughly 0.5 dB if my mental arithmetic holds up.
Title: Re: Silver Drop Cable
Post by: burakkucat on August 25, 2015, 11:18:02 PM
Somebody suggested something similar (http://forum.kitz.co.uk/index.php/topic,14920.msg278569.html#msg278569)!  :angel:
Title: Re: Silver Drop Cable
Post by: NewtronStar on August 25, 2015, 11:39:40 PM
One thing thay stands out each copper join should be welded (soldered) togeather rather than being butt joined as this can cause high resistance at each joint, an the reason why an HR fault on Openreach network is the cause of most failures  >:(
Title: Re: Silver Drop Cable
Post by: Weaver on August 25, 2015, 11:44:47 PM
How do gel crimps work? Knife-like cuts into the conductors?
Title: Re: Silver Drop Cable
Post by: burakkucat on August 25, 2015, 11:54:47 PM
The current standard method of jointing is by crimping.

It must have been around 1965, I can remember watching a GPO jointer at work on a lead-sheathed E-side cable. The insulation, back then, was paper and each joint was made by twisting the two conductors together. Once the twisted joint had been made, a paper insulating sleeve* was then fitted and the completed joint was "laid back" with all the other completed joints. The final act involved a hard-wood former, a bucket of molten lead, sheets of lead, a soldering-iron heated on a gas-ring and a "dressing" hammer. Plumbing at its most intricate!  :)



* The paper sleeves were kept in a bucket, with lid, which was gently heated over a gas-ring to ensure near-absolute dryness.
Title: Re: Silver Drop Cable
Post by: Weaver on August 26, 2015, 02:54:36 AM
The knife-cut seems to work over a seemingly very small cross-sectional area, which says hugh resistance. Presumably the colossal pressure melts the conductors, which equals a really good conductivity, lower resistance connecting. Just squeezing one wire against another might not actually have that much contact cross-sectional area as the conductors might not actually be touching closely over the whole of that apparent area, and the conductors might not melt together so well, or at all. The knife-cut method also involves two changes of metals, A-B-A. This isn't ideal but unavoidable presumably, as Cu-Cu-Cu would be too soft, and the knife blade link material absolutely has to be really hard.

Does any of that speculation sound right?

[Actually, apologies for going completely off topic, unless we can say this is relevant because it's all about lowering total end-to-end resistance.]
Title: Re: Silver Drop Cable
Post by: Gareth_R on August 26, 2015, 12:00:03 PM


It must have been around 1965, I can remember watching a GPO jointer at work on a lead-sheathed E-side cable. The insulation, back then, was paper and each joint was made by twisting the two conductors together. Once the twisted joint had been made, a paper insulating sleeve* was then fitted and the completed joint was "laid back" with all the other completed joints. The final act involved a hard-wood former, a bucket of molten lead, sheets of lead, a soldering-iron heated on a gas-ring and a "dressing" hammer. Plumbing at its most intricate!  :)




* The paper sleeves were kept in a bucket, with lid, which was gently heated over a gas-ring to ensure near-absolute dryness.

I can remember being trained to do that when I was an apprentice :-)
Title: Re: Silver Drop Cable
Post by: Black Sheep on August 26, 2015, 02:09:36 PM


It must have been around 1965, I can remember watching a GPO jointer at work on a lead-sheathed E-side cable. The insulation, back then, was paper and each joint was made by twisting the two conductors together. Once the twisted joint had been made, a paper insulating sleeve* was then fitted and the completed joint was "laid back" with all the other completed joints. The final act involved a hard-wood former, a bucket of molten lead, sheets of lead, a soldering-iron heated on a gas-ring and a "dressing" hammer. Plumbing at its most intricate!  :)




* The paper sleeves were kept in a bucket, with lid, which was gently heated over a gas-ring to ensure near-absolute dryness.

I can remember being trained to do that when I was an apprentice :-)

A skill very, very, very rarely called upon these days.
Title: Re: Silver Drop Cable
Post by: burakkucat on August 26, 2015, 03:30:52 PM
I can remember being trained to do that when I was an apprentice :-)

b*cat performs his best Japanese-style bow towards a true maestro of the art.  :)
Title: Re: Silver Drop Cable
Post by: Starman on August 26, 2015, 03:35:16 PM
Unfortunately it is also a lost art with mains electrical cable jointing which is my trade. The elder jointers have long since retired along with the lost skill to work on the more uncommon types of cables which if we have to work on now days has to be done isolated. Joints for LV voltages were all solder and plump up to the mid 1970's, and HV side up to mid 1980's. Now days its all shear off connectors, and resin mixtures which don't get me wrong will require a high level of skill but the art form when you have to break down a joint that's 60 years old and you see the skill rapping lays upon layers of paper you do always admire those old chaps.