I only managed to get to the site for the first time today. Too many other projects have cropped up unexpectedly. I was finally able to terminate the cable and can confirm that over a TDR measured length of 22m I'm getting a delay skew of less than 7ns for each pair.

A long bit error rate test shows zero errors too (10⁷ random 1518 byte packets at a link speed of 1GBps). The link happily runs at gigabit speeds which is all it needs to do for the installed Unifi UAP-AC-IW access point.

I still don't know what the cable is but there's about a metre and a half of it inside trunking that I can get to to see what's written on it. I'm back in the morning so will have a look. It's definitely for structured cabling use, I just don't know what use

I haven't gone searching for the electrician's card yet.

In reply to a post by Pheasant:

Did it work/test out as expected Sarah and/or were you able to find out what the sparky actually installed?

I've got it

It's Acohome Grade 2 TV 4P LSOH-FR and I think that 'odd' describes it perfectly. I've never seen anything like it in the UK.

caffn8me

Glad to hear it all worked, but never seen or heard of anything like it. Interesting set of services all bundled together and I can see how it could be useful in a residential setting historically.

Back in 2004 the early FTTP equipment offered phone, TV and BB over two different light frequencies, this would have been useful for cabling from the ONT around a residence.

Well the information in the PDF says it's good for gigabit using all four pairs, so as long as you where not hoping to put 10Gb Ethernet down it anytime soon it you are fine as your measurements would indicate.

In reply to a post by kitcat:

caffn8me

Glad to hear it all worked, but never seen or heard of anything like it. Interesting set of services all bundled together and I can see how it could be useful in a residential setting historically.

Back in 2004 the early FTTP equipment offered phone, TV and BB over two different light frequencies, this would have been useful for cabling from the ONT around a residence.

Yes, luckily it's a short cable run to a guest bedroom and it works fine. I'm certainly going to be far more specific in the future and look at any cables before installation. This stuff is a complete pain to terminate in RJ45 plugs because of the disparity in core diameter.

Where I am in London, FTTP from Community Fibre uses two different frequencies; one for domestic customers and the other for business customers.

Edited by caffn8me (Wed 02-Sep-20 19:54:06)

In reply to a post by jabuzzard:

Well the information in the PDF says it's good for gigabit using all four pairs, so as long as you where not hoping to put 10Gb Ethernet down it anytime soon it you are fine as your measurements would indicate.

The PDF also says "Longueur maximale de câblage préconisée : 45m" - the maximum recommended cable segment is 45m so that's not even Cat5e standards.

If there was ever any likelihood that the client would need 10GB in that bedroom I'd have the electrician replace it but we're good to go.

In reply to a post by caffn8me:

In reply to a post by Pheasant:

Did it work/test out as expected Sarah and/or were you able to find out what the sparky actually installed?

I've got it

It's Acohome Grade 2 TV 4P LSOH-FR and I think that 'odd' describes it perfectly. I've never seen anything like it in the UK.

That is a wacky one! Perhaps the thinking behind the thicker gauge and seperate screen of pair 4 is some better attenuation performance and screening for running digital TV over that pair - they are hinting at 2200 MHz for satellite, but I really can't imagine you'd want to run over that rather some some proper coax, either double or quad-shield stuff. Oddball stuff.

In reply to a post by caffn8me:

In reply to a post by jabuzzard:

Well the information in the PDF says it's good for gigabit using all four pairs, so as long as you where not hoping to put 10Gb Ethernet down it anytime soon it you are fine as your measurements would indicate.

The PDF also says "Longueur maximale de câblage préconisée : 45m" - the maximum recommended cable segment is 45m so that's not even Cat5e standards.

If there was ever any likelihood that the client would need 10GB in that bedroom I'd have the electrician replace it but we're good to go.

No doubt your segment length is under 45m, so it will 'do' Gigabit happy days, but defo not to Cat5e limits (up to 100m channel) let alone Cat 6 or Cat6A for driving 10GbE. It does the job though for now.

In reply to a post by Pheasant:

No doubt your segment length is under 45m, so it will 'do' Gigabit happy days, but defo not to Cat5e limits (up to 100m channel) let alone Cat 6 or Cat6A for driving 10GbE. It does the job though for now.

Yes, it's lucky that it's only 22m (according to TDR). The switch is bang in the middle of the house and the furthest ethernet run in the other direction is also 22m so it would have been 44m total had we had the switch at the end of the house