Try to utilize (and then write using) complete sentences, idiot.
Two pairs have one level of twist. The other two have another level of twist.
One set of pairs is more twisted than the other set.
Try to grasp that fact, child.
One set of pairs is twisted less than the other set.
Simple math and logic, but I thought I'd spell it out for you.
Didn't find your answer? Ask the community — no account required.
C
Chieftain of the Carpet Crawlers
Oh boy!
Massa Wiah Twistah Boi!
I was twisting wire before you even knew what "electricity" was that 'made your TV work' when you were physically a boy, boy.
Come back when your mental age actually gains about 10 years.
I tire easily of twelve year old mentalities.
At the rate you "advance" however, you'll be 95 years old before you turn 19.
C
Chieftain of the Carpet Crawlers
You are apparently the one here who thinks you know so much about the COMMUNICATIONS spec from being a mere WIRE BOY for a few years.
The SPEC uses it. Period. Get a clue. Been that way (the twist pith differences) since CAT5 and CAT6 follows the practice.
The pairs, in fact, all four have a different twist pitches and if your machine does not fine resolve the twist pitch, then it is a piece of s*it machine.
formatting link
They are all four different, and by 'general' appearance they look like two pairs at one pitch and two at another.
They are close to that, but are actually all slightly different in a fully conformal manufacturing process.
I have seen vendor data sheets which declare it and have tables for it even, while offering older spec wire all twisted the same as well.
If you hook up the old stuff (or likely your s*it), you will not get a full 100 base T handshake, much less anything faster. Even my new std cable modem blinks a different color on the front panel indicators if I use a s*it cable to link to it.
We used shrouded connectors at work and shielded CAT6 wire and insure that the twists remain right up to the connector header and crimp the drain into the shroud. The receptacle has to be shrouded CAT6 as well and the internal cable on the other (back)side of that bulkhead as well, if that is what it is plugged into.
I make clean, high speed EYE. AND I know why.
You make fuzzy, spur laden EYE. Because you don't even know what one has to do to RETAIN CAT6 compliance throughout a circuit path. The ENTIRE path.
You don't even have part of the clue. The ENTIRE clue.
But you probably know how to make the wire twisting machine twist wire.
You just likely have no clue how accurate the twisting has to be. That is based on your pathetic responses.
J
Jamie
What a moron... A complete ignoramus. I wonder what the rest of your family looks like? Most likely all four legged.
Jamie
J
Jamie
Blahhhhhh , Blahhhh, Noise , Noise. All Random. You can't even decide if it's white, or pink today..
Why don't you go back home, your mother forgot to dress you. You forgot to take off the lipstick and dress you were fantasizing in last night.
Look up Brand-Rex+Bcc-Brand-Rex- BCC-General and General Cable.
If you look hard enough, you may even find a picture of me sitting in one of the groupies..
Go play with your crap products. We actually make products that work better than others. There is a reason for that. But you wouldn't know it if it was staring at you.
Maybe you should come and visit us, I'll introduce you to one of our irradiation units set on 3Mev and make sure you get a good look at the scan horn.
What a hopeless case..
Jamie
C
Chieftain of the Carpet Crawlers
No thanks. Especially if your 'expertise' is part of their 'formula' for success.
Not interested in looking at a photo, trying to find the dung heap in it.
J
josephkk
formatting link
Yes, it does. The twist differences are required by TIA-568. It is also done with Cat3. Moreover, the twist of each pair is varied over the length of the cable.
Usability for any given purpose is a different question.
J
josephkk
formatting link
can
several
Cat 5E has about 60 percent more useful bandwidth.
?-)
J
Jamie
You should see the machine in operation that does that all in one pass !
Jamie
T
Tom Del Rosso
Is the skew mostly from the difference in the twist?
In an old logic analyzer they had about 10 or 20 feet of ordinary ribbon cable used as a delay line.
Over 100M the difference in length due to the twist could be 45 feet.
Reply in group, but if emailing add one more
zero, and remove the last word.
J
josephkk
can
several
=20
also
!
It would be a kick to see it live. I have seen videos of the building of
600 pair armored cat 3 cables.
?-)
J
John Larkin
Apparently so. The CAT6A-U/FTP (individually shielded pairs) has much less skew. I assume they don't vary the twists on that version.
That might just work!
The spec is 45 ns per 100m, and we're measuring almost that on CAT6A-F/UTP, so the equivalent delta-length is 30 feet or so. Awful when skew matters.
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
T
Tom Del Rosso
It must have. Gould Biomation beat HP in that market at the time.
You mean it might work in your app? Glad I mentioned it.
Are alternate grounds enough to make up for the lack of twist? I guess so, but my inexperienced intuition tells me there would be crosstalk.
They had the ribbon fan-folded and jammed in a tight space. I'm surprised there were no ghost pulses as well.
Of course you could put foil on both sides before folding, but they didn't.
I first think of Grace Hopper who used 1-foot lengths of wire for her demo, but that really is the speed in vacuum so 8 inches makes sense.
Reply in group, but if emailing add one more
zero, and remove the last word.
J
Jamie
600 Pairs is a lot. Years ago when telephone wire was in we used to make the wire that drops down in the ocean with very many pairs. If there was a defect on that cable, it was repaired in house.
We'd find it with a fault analyzer and open the jacket. Fish down in there with surgical tools and repair it.
Jamie
W
whit3rd
Yeah, it's a LOT nicer when there's a standard for the connector. SCSI, for example: I started making a list of those connectors, and there were only ... eighteen. That was before SAS, of course.
T
TunnelRat
Thank God for, and long live SAS!!!
T
Tom Del Rosso
Do any experimenting with that idea?
Reply in group, but if emailing add one more
zero, and remove the last word.
L
langwadt
look at the "fast" parallel ata cable that is, half the pitch of standard ribbon cable and half of the wires are ground
must be a decent transmission line for 66MHz data rate
-Lasse
C
Chieftain of the Carpet Crawlers
They are commonly referred to as "differential pairs".
There are also twisted pair ribbon forms the SCSI boys used to use.
K
krw
AlwaysWrong, "half the wires grounded" is *not* the same as "differential pairs". There is nothing "differential" about it.
Join the Discussion
Have something to add? Share your thoughts — no account required.
Didn't find your answer?
Ask the community — no account required
Report Content
You are reporting this content to the moderators. They will look at it
ASAP.