Dear winston1,
I have no idea what it is that you meant by PLT (although I have "looked it up")
Please explain.
Running ethernet and CCTV cabling in house
- Thread starter joe384
- Start date
I have no idea what it is that you meant by PLT (although I have "looked it up")
Please explain.
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But the technology still radiates significant amounts of wide spectrum radio frequency energy that can interfere with FM broadcasting ( 87 -- 110 MHz )
Power line technology. Putting data at many MHz along power (mains) cable that is designed for 50Hz.
Not to mention air traffic control 108 to 137MHz. Don't even assume that interference at ground level won't affect planes thousands of feet in the air. Read this:
https://www.ofcom.org.uk/about-ofcom/latest/features-and-news/interference-issue
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It is not designed for 50HZ! What a curious notion. It is designed to carry a certain current at a certain voltage.
Is it no good for 60Hz then?
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Have you tried connecting the tone to one wire and to earth? It quite often gives some results albeit a bit hit and miss.
Lets not pick holes. It is designed for use in the UK which uses 50Hz. I'm sure it is OK with DC or 60Hz, 400Hz even. But it is not designed for RF frequencies.
Says King Pedant.
I bought a reasonably priced tone generator, turned off all power at the CU and connected the black crimp to the screening and red to the core. I'm not quite sure if this is correct but it did give some interesting results.
The only places I could pick up the tone were:
* Within 3 feet of the tone generator
* At the telephone jack and aerial jack in the master bedroom
* Near the ceiling at the middle of the house (near the top of the roof)
Now I am pretty certain the cable is not the bedroom one (I have already labeled this up) but what is interesting is I spent a fair few minutes waving the detector around every socket in the house, walls, ceilings etc and nothing except what's listed above.
It seems to me there is something in the roof space. It is a chalet style house with dormers so I have no loft and no loft hatch, only access is through fan/vent in the bathroom so I am just going to hook up a TV to the cable to start off on the random off chance an aerial is installed in the roof space.
I am a little confused why the master bedroom jack can get the tone but maybe it's because the cables are following the same path upstairs
Going back to the ethernet wiring, I would like 2 sockets in the lounge.
I currently have (I think) screed on the floor downstairs. Above the lounge some of the roof is flat, so I will either have to route along the floor or cut holes in the ceiling and then channel down the wall and patch up.
Am I better off going the ceiling route? I read that making a channel in screed could be really messy. The other option is some flat cable and cut a channel in the underlay when the floor goes in.
I currently have (I think) screed on the floor downstairs. Above the lounge some of the roof is flat, so I will either have to route along the floor or cut holes in the ceiling and then channel down the wall and patch up.
Am I better off going the ceiling route? I read that making a channel in screed could be really messy. The other option is some flat cable and cut a channel in the underlay when the floor goes in.
That is not an option for mains cables . .
From your description, you are unlucky enough to have a modern new build that is designed to be non-maintainable. I would have a very special place in hell for the f'wits responsible for these - especially when (as it sounds in your case) they've got extra out of the way to make things difficult.
That's tricky.
Based on your description, I would also assume that one of the cables has been put in for the aerial. I take it you've looked around the outside to check that there isn't a coil of cable hanging out of the wall somewhere ?
Indeed they have - and things have got worse, not better. PLTs have been going to progressively higher frequencies, so impact more and more stuff - not less. It's claimed that they notch out important frequencies, but yeah, who would trust a bunch of ****s who are happy to make & sell interference generators in the first place.
There's plenty of information on https://www.ban-plt.org.uk, though I don't think it's been updated for some time - no need really, f'all has changed, the crap is still on sale, the authorities are still working on the basis of "we've found a loophole to show it's not under my jurisdiction so we've dodged a bullet there", mains wiring is still not a suitable cable for VHF, and they still spew out lots of interference that will kill radio, kill your DSL, etc, etc.
And IIRC there's a video on there where they setup a system where there's no coupling between two sockets other than via radio signals - i.e. the signal cannot go via the wiring. Guess what, they get a perfectly working connection.
Now if all they affected were those daft enough (or desperate enough) to use them, fine. But they cause problems for everyone in the area - from memory problems have been shown at 1/4 mile distance, which on modern stacked shoebox estates can be a lot of houses.
There's definitely a knack to using them.
The style used by BT and others have a variable sensitivity probe - so you can use it on high sensitivity for finding stuff, and then turn it down as you narrow in on the individual cable/pair, and right down as you get to the contact stage. But because you do get crosstalk, for a positive ID you need to short out the pair to show that the signal goes away.
If you put the generator across a pair, or across core and screen of a coax, then it's not good for tracing a cable - by design these cables are low leakage. It's better to put the generator between one wire of a pair/the screen of a coax and an earth so that the cable then acts like an aerial. When you think you've found the other end, move the generator to be across the pair/core & screen of the coax to double check. Downside of this method is that you have a lot more crosstalk, so will find the signal coupled to other cables, especially if they are bundled together for part of their run.
Yes, already planning on this - I know all the technical details it's just running cables through walls that I know nothing about.
Yes it is a new build but I think builders will always do the least work needed!
The house is a semi, and I can't see any cables or access holes (unless there is something hiding behind the guttering).
I have ordered some aerial connectors so will test the cable for a signal (should have done this ages ago really)
The other option is to take the bathroom fan off and put a camera up there to see what is up in the roof space (this needs to be done anyway as I realised the hose is not connected!)
many builders will do less than the least work needed.
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