Freeview HD reception

[lucid]

maybe lucid will explain ... but what is the expected strategy/routing driving two sockets , a Y juntion somewhere on the house exterior .... is that where ingress might be ?

Splitting for multiple TV points depends mostly on the signal strength from the existing aerial and how many points to serve. There are other factors too, such as whether there's a magic-eye-type control system being used, and what the customer's future plans for the house and further TV points might be.

Where the signal is very healthy, and there are maybe no more than two or three TV points to run, then it may be possible to split passively. Signal strength is reduced, but the signal to noise ratio (SNR) remains unaffected. Passive splitters live as close to a central point between the receivers/TVs as possible. For example, taking the roof aerial and splitting for say the lounge and kitchen TV, the splitter might be at ground level.

Active or powered splitting is used where there are too many TV points to supply passively, or where the signal strength from the aerial is low. Powered splitters add noise, so they live as close to the aerial as possible to get the best SNR from that. The amplification on their outputs is there to compensate for the longer cable runs from the roof or loft to the TV points.

In all cases, it's perfectly possible to create moisture-proof joints where the splitters and amps use F connectors.

For outdoor use I fit compression connectors that form a watertight seal on the cable, and the plug end has an inner gasket to seal against an F socket head. Properly fitted to sound WF100/RG6-size cable, and correctly tightened, these are all that's required.

For indoor use including lofts the compression connections are a bit OTT. I use screw-on F connectors with a gasket seal. Once again, properly fitted and correctly tightened, they don't come loose unless a cable gets yanked severely. The moisture seal is good for about 7-10 years.

I also carry self-amalgamating tape. This stretchy rubber tape is useful for temporary patch-up jobs or sealing where someone has bodged with aerial plug back-to-backs outside. Once a joint is wrapped, the tape bonds to itself and also partly to the things it is wrapped around.

Breaks in the outer sheath of coax cable can't be fixed economically. If UV and weather exposure has caused a cable sheath to crack in one place, then chances are it will be going or gone in other places too. Moving the cable around to fix one spot will open up weak points elsewhere, so replacing the whole lot with better quality coax and decent end fittings is really the answer.

 

[lucid]

TV aerial people came this morning and all fixed now!

I'm glad you're all sorted.

 

[Merlin5]

Me too lucid, and thanks very much for all your advice, it really helped me understand things better and at the very least, know what brand of cable to expect.

That's good -
... they changed all the cable then - your comment about not being able to get up to the aerial, confused me - was the living room an internal spur.

(freeviews been breaking up in Cambridge for last 3/4days on some channels - Sandy Heath transmitter
... but I couldn't see any information about atsmospheric effects, or explanation, like mux changes )

He said that it was not possible in this weather to get further up the roof. To be fair, the people last year came in the height of summer, but at the moment, the roof is covered in slippery moss he told me.

He changed the cable running from the aerial to the back of the house to my bedroom. But not the old cable at the front, since he plugged the cable connector in my living room to his machine and said it's spot on. So I'm assuming that if his machine said it's all good that presumably there's no damage to that cable. Perhaps lucid can confirm if that's the case. But should there be any problems with the front cable and they have to come back, it should only cost the same again, which would still be within my original budget. But these guys have been going for years so I trust that his decision to only change the bedroom cable is fine.

Oh and quick name drop, he told me they were once working on some property in central London that Cher was renting and she turned up. I don't know any more than that, just thought I'd mention it.