Author Topic: Mounting Cord wire Color coding for older keysets  (Read 1510 times)

Offline Key2871

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Re: Mounting Cord wire Color coding for older keysets
« Reply #30 on: July 15, 2021, 02:23:08 PM »
Are they paired by twists, or bundles?
Can't imagine straight through wires.
KEN

Offline Jim Stettler

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Re: Mounting Cord wire Color coding for older keysets
« Reply #31 on: July 15, 2021, 08:00:53 PM »
Are they paired by twists, or bundles?
Can't imagine straight through wires.
Twisted wire was used early on to help with RF type interference (possibly ground Hum as well), this is the 2-3 conductor baseboard type wiring. color thread or ridge to identify conductors,

 then straight through wire was used (think Quad). 25 pair was straight through

Once you hit CAT 3 wiring, then they started twisting for RF again.
CAT Rated 25 Pair has twist.
I think you get more twist per inch based on a higher CAT number.  Cat 5 has more twist  than CAT 3.
The number of twist per pair also changes. To maintain rating you need to keep the twist intact as close to the termination as possible.
This is for data speed and RF.
If you kink CAT 5 wire you can slow down the data.

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To get back on the subject.
I think Cloth 26 pair was straight thru. the 26th pair was a spare pair.
Cloth colors were selected based on current dyes and the colorfastness of available colors ( per a bell lab report I read long ago)*

Jim

* it is fun to read some of the Bell Lab reports. Those guys were intense nerds doing a lot of pure research because they had funding to do so.
There are a lot of Bell Lab publications in the Internet archive.
https://archive.org/

You live, You learn,
You die, you forget it all.

Offline Key2871

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Re: Mounting Cord wire Color coding for older keysets
« Reply #32 on: July 15, 2021, 08:37:58 PM »
 Jim, I am aware of why they twist wires.
I asked John because the picture he posted looked like straight through run, and yes for RF that's not great for the service, but more so for the installer finding proper pairs would also be difficult. When I first started working with cat 3 25 pair I had issues as some of the pairs weren't well twisted, but at least the color code helped me.
I can't imagine finding pairs in straight runs like that, yikes that could have taken much longer to verify the pairs.
KEN

Offline 5415551212

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Re: Mounting Cord wire Color coding for older keysets
« Reply #33 on: July 15, 2021, 08:54:58 PM »

I asked John because the picture he posted looked like straight through run..

Greetings the pairs are slightly twisted, about as good as a cat 3 and its Stephen here not John  :)
I have salvaged 15 pair, 25 pair and 50 pair in the brown.
Its nice stuff, good condition very similar to the 6 pair that I would see with old interphones.
The interesting thing about the old 50 pair is there are no binder groups, it's extremely hard to tell  whats what in it.
You all inspired me to slice into the 50 pair more and upon very close inspection there is a slight white stripe on the 2nd binder group.
I was able to isolate all the groups.
More photos attached, they are hi-res so you can zoom in and see them close up.
(Ill probably run some of the 50 pair in my house for linking up old phones)
Also note the red-white spare pair as many large cables have them and bare ground wire, which I had not seen before.

Offline Key2871

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Re: Mounting Cord wire Color coding for older keysets
« Reply #34 on: July 15, 2021, 09:53:45 PM »
Sorry Stephen, my bad.
But thanks for clearing that up. :)
Yea from the pictures I can't tell any real twists.
Is that still 22 gauge? Or heavier.

I've seen older station wire that was quite heavy, an when I tried using 3M splice beanies it was too large to use those.
I can imagine that would be quite difficult matching pairs if they aren't twisted well. I've run into some cat 3 50 pair that was the same way, very loose splices took more time to sort the pairs, some color markings were also poor that added to the time to make sure I had the correct pairs.
« Last Edit: July 15, 2021, 09:59:40 PM by Key2871 »
KEN

Offline 5415551212

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Re: Mounting Cord wire Color coding for older keysets
« Reply #35 on: July 16, 2021, 12:43:59 AM »
No worries I dont think I had ever properly introduced myself.  :D
I am pretty good at guessing 18 awg and larger from my many years as a sparky but 20 - 24 awg is all a blur.
Sometimes 8awg and 6awg still fool me.
I could break out the mic and measure it.
If any of you want some of this ill send it to you for the cost of shipping.
send me a PM.
After I cable every room in my house with 75-100 pair I think i'll be good for a while  ;D

Offline Jim Stettler

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Re: Mounting Cord wire Color coding for older keysets
« Reply #36 on: July 16, 2021, 01:17:09 AM »

After I cable every room in my house with 75-100 pair I think i'll be good for a while  ;D
Over design always give a warm fuzzy feeling. it reminds me that , despite management, knowledgeable techs still rule.
Just pointing out the obvious,
Jim
You live, You learn,
You die, you forget it all.

Offline Key2871

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Re: Mounting Cord wire Color coding for older keysets
« Reply #37 on: July 16, 2021, 04:53:59 AM »
75-100 pair? Woe that's serious cable.

As far as still getting 6 and 8 AWG confused that can be understanding.
I used to be a sparky, that was a while ago now.
But I knew a guy who had 50 pair riser cable, a spool full. I thought that was crazy, but he thought I could get a 25 out of it but realised it had no sheath separating the bundles.

I think that was a 1000 foot of cable that went to waste.
But what do you have planned with all that cable?
Putting in a serious 1A2 or more telephone system, or even larger EKS??
KEN

Offline 5415551212

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Re: Mounting Cord wire Color coding for older keysets
« Reply #38 on: July 16, 2021, 02:12:41 PM »
I would have never bought the cable but it was heading for the recycle bin on a large office remodel, and its in pretty good shape, sections of it were in conduit so its almost  brand new.
And I have got to do some other work in the attic this year, we live in a one floor house so I can drop a cable down the wall to each room. I think I have 3 cuts that will be long enough.
I do have some 1A2 and interphone type projects going on in my limited spare time, so it will be a neat way to hook up phones as I collect them.