Hi all
I'm new to this forum but I have searched extensively and don't think I can find an answer to my question so apologies if I've missed it elsewhere. My question is whether it is better to have the internal wiring between the end of the drop cable and the master socket be CW1308 or CW1724 (essentially CAT5E spec), specifically with regards to g.fast?
As a bit of context: my drop cable enters the property through the top of my front door frame and immediately enters a BT80 junction box where it is connected to "alarm style" untwisted cable (put in by a previous owner). From there, this untwisted cable runs for about 8 meters to the master socket (alongside several mains wires for some of that, as well as the fuse box for the house). There is then a 0.25m rj45 to rj11 patch lead between the master socket faceplate and the ZT link MT992 Openreach modem.
I am looking to move the master socket to make the internal cabling is short as possible and replace the alarm cable with standard spec CW1308 or CW1724 (or CAT5E if I can't get CW1724). This will result in the distance between the junction box and the master socket being about 3 meters (and more crucially, I suspect, it no longer running alongside the mains).
CW1724 doesn't seem to be very easy to get hold of, with the only place I can find being one eBay seller who does it in various lengths (10m here:
https://www.ebay.co.uk/itm/10m-White-CW1724-2-Pair-CAT5E-BT-CABLES-Twisted-Telephone-Network-CW1308-10m/252386379743). Does this seem legitimate? If not, I think I can just use CAT5E since CW1724 is the same spec but 2 pairs instead of 4.
The reason I ask this is because there seems to have been a little research into whether CW1308 or CW1724 is better for VDSL with somewhat inconclusive results, but suggesting CW1308 might be slightly better given the actual wire is shorter for a given length of cable, since it has fewer twists. However, I want to know if this still holds for g.fast, since it operates at higher frequencies (and therefore may benefit more from the higher interference rejection of having a higher twist count??)? As I understand it Openreach switched from using CW1308 to CW1724 early in the VDSL rollout but switched back long before g.fast was introduced. However, I don't know if this was just for cost reasons, or whether they found CW1724 actually was worse?
I realise this debate may be fairly moot and in practice there may be no noticeable difference between the 2 cables but figured I'd ask since I'm trying to maximise my speed. For reference, the highest throughput speeds I have observed from the somewhat sporadic speed tests I've done is 128 down/22.9 up. I can't see the line speed since the MT992 modem is locked down but when the engineer installed it he said he got a sync of around 150 on a distance to cabinet of just over 300 metres. My BT wholesale checker stats show a clean range of 153.8-196.4 down/11.1-27.6 up and an impacted range of 101.7-156 down/8.6-18.1 up so hope I can get a little more on the downstream than I'm currently getting (I know the wholesale checker stats have to be taken with a pinch of salt).
Thanks in advance to anyone who can help me with this!
TLDR: For the three metres between the drop cable junction box and the master socket is it better to use CW1308 or CW1724 for a g.fast line?
EDIT: before anyone says it, I know I'm not supposed to touch the cabling before the master socket, I accept the risks.