Digital reception

Hi,

Having had a completely new roof top ariel, booster and coax wiring last year our digital tv reception became wonderful, even though it was split to 3 seperate tv's.

However, for the past week or so we've found the itv channels on digital have become pixilated with a poor picture. The surprising thing is, while the itv channels are like this, the bbc channels are perfect!!!!!

Is there likely to be a fault with our equipment or is the fault with the itv broadcaster ie, how can bbc be perfect while itv is not?

We're in North Yorkshire and get our signal from the Teesside transmitter, and by the way the ariel was correctly set up with a signal meter.

Any advice appreciated, ta

are you fully digital yet??

different batches off channels are transmitted together at different signal strengths

http://www.ukfree.tv/fullstory.php?storyid=1107051122

I had this and I wiggled the ariel plug on the back of the telly. My 1 year old daughter like to yank on it.

Big All, no we still get analogue which is usually poorer than digital (lines across the screen) Bilsdale is our transmitter and we're near the edge of it's area.

thatbloke, i've tried the wiggle at the back of the set lol, no better, all 3 tv's show the same.....i'll check connections in the loft tomorrow though

Do you have mice? I would check the cables as well for any damage. Also check the booster is still getting power.

I fitted a booster in my loft and it ran for years without problem. Then it went down. No good reason why. Replacement had through for digi-eye that stopped working digi-eye but continued to work as an amp.

So going on my experience pre-amps do fail in some odd ways.

However most digital transmissions are split into multiplexers with each multiplexer having a group of stations.

Two likely causes are reduced power for poor multiplexer or that one is at a widely different frequency to others.

Here in North Wales we have three transmitters and Freeview is constantly retuning as a result. I know the cure and that is to change aerial from horizontal to vertical and re-direct to Wirral transmitter. However not really bothered I use satellite instead.

But for those who do use freeview it must be a real pain and because Winterhill still uses the original narrow band I still use a banded aerial. When it re-tunes to Moel-y-parc the aerial is out of band and we get poor signals.

This is a local problem and I would be able to cure it you may have a similar local problem and unless some one in the same area replies we could spend ages and still not find it.

My parents lost a freeview channel because of interference from a neighbours sky box which was using channel 68 to send sky to sets in the house but was also blocking freeview on same channel. In their case they said channel 5 was no good.

Any analogue device. VCR, games machine, Sky box etc. May block out a digital block of signals. Either because on the same frequency or a harmonic of the frequency.

So step one is turn off VCR etc. Does that improve things. Neighbours devices harder to find but note if better when they are on holiday.

Aqua said:

Big All, no we still get analogue which is usually poorer than digital (lines across the screen) Bilsdale is our transmitter and we're near the edge of it's area.

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the signal will be boosted several times when analogue is turned off at present the power is very low to stop interference

I wondered why the ariels in some places where at a funny angle! Like on the side.

Im sure I've seen them like this in Wales or the lakes.

xr4x4 said:

I wondered why the ariels in some places where at a funny angle! Like on the side.

Im sure I've seen them like this in Wales or the lakes.

Click to expand...

That's to do with whether the signal is from a main transmitter (horizontal aerial alignment) or a repeater transmitter where the aerial has to be aligned with the fins pointing vertically.

Update...of sorts, i've checked all the cables in the loft for rodent attack and all are fine, all connections are good as well.

I'm really at a loss to understand the problem, as previously mentioned the digital bbc channels are fine, digital itv channels are pants.

How on earth can that happen from the same transmitter?

Aqua said:

Update...of sorts, i've checked all the cables in the loft for rodent attack and all are fine, all connections are good as well.

I'm really at a loss to understand the problem, as previously mentioned the digital bbc channels are fine, digital itv channels are pants.

How on earth can that happen from the same transmitter?

Click to expand...

they are clumped in groups and transmitted at different strengths a bit like beers in a pub the stronger the signal the better the results

Thanks big-all,

Nice ale based analogy which i appreciated having recently got back into drinking bitter after 20 years of lager drinking

Anyway, i suppose we just have to wait until the itv digital signal gets better because at the moment it's unwatchable

But while we wait here's a posser for you all to consider -

Everyone knows transmition is going to be switched to digital so why do they have the digital signal low and the anologue signal high - surely it makes better sense to have it the other way round to encourage anologue viewers to get theirselves digital ASAP

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it will ruin or interfere with the ana signal

what i do with a weak signal is place a booster in the cable
i have one in the upstairs bedroom below the ariel in the loft distributing to up stairs and passes the signal 20ft down stairs
it goes through a freeview duel recorder box then 2 video recorders the signal then goes through another distribution amp to all tv in the house
there is a further 20ft to the kitchen tv with a further single booster to the shed another 30 foot away
this allows me to watch any recording on any telly

Aqua said:

However, for the past week or so we've found the itv channels on digital have become pixilated with a poor picture. The surprising thing is, while the itv channels are like this, the bbc channels are perfect!!!!!

Click to expand...

My parents TV did this Saturday night. All the HD channels vanished as did several of the SD ones, even BBC1 and ITV were breaking up and badly pixelated. We wound up watching on analogue!

It could just be atmospheric conditions, solar flares and whatnot. My folks have just come back from a week in Spain and the Brits out there are complaining of suddenly rubbish satellite reception.

Thanks for all the replies everyone, i've now discovered the problem.....

It was the Wolsey WFAV-425 4 Way Masthead amplifier that caused the problem. Reception was getting worse so i decided to take the aerial out of the amplifier in the loft and connect direct to the main TV.

All channels on the TV worked perfectly, to be sure i checked to all the other TVs in the house (all OK) and finally went back to signal through the amplifier (rubbish again).

So there it is the amp has obviously gone wrong somehow, the unit is less than a year old so i've emailled the supplier re the problem and await their responce which hopefully will be a replacement unit....