Freeview poor BBC signal

[alferret]

We have a communal tv aerial (mansfield) which has just been switched over to DVB.
I purchased a Agora STB from tesco. (cheap £15)
It picks up all channels but ..... All BBC channels have very low signal strength (<10%) and drop out\pixelate quite a lot, every other channel has 100% (full bar) I have tried a SLx1P booster which has made zero difference.
Any idea's?

I'm not overly concerned as we have sky in the front room and bedroom and this is a box for our girls room, it would be nice if I could get all BBC chnls for her.

[Kymmy]

Is the communal antenna a decent wibeband one? Just that analogue you can get by with low signal and the antenna just needs to be tuned to a particular section of the band (every area was slightly different freq so they didn't interfere) where as digital uses a lot more of the bandand needs a better signal strength to avoid cut-outs pixilation.

For digital and a communal set-up you need a good wideband antenna and a masthead amplifier/splitter, that way every person (or group of people) are getting a good signal.

Boosters that plug in near the TV are not only trying to boost the signal but they also end up boosting the noise caused by electrical wiring, appliances and other stuff picked up by the co-axial cable.

Kymmy

[Graham M]

Not forgetting that you can't boost signal that isn't there in the first place so a booster before a 1m cable will be pointless.

[Losttheplot]

You don't have any BBC channels duplicated do you? Some STB's if they see more than one transmitter can show the same channels twice, with the second version of the channel getting higher channel numbers.

[alferret]

Is the communal antenna a decent wibeband one? Just that analogue you can get by with low signal and the antenna just needs to be tuned to a particular section of the band (every area was slightly different freq so they didn't interfere) where as digital uses a lot more of the bandand needs a better signal strength to avoid cut-outs pixilation.

For digital and a communal set-up you need a good wideband antenna and a masthead amplifier/splitter, that way every person (or group of people) are getting a good signal.

Boosters that plug in near the TV are not only trying to boost the signal but they also end up boosting the noise caused by electrical wiring, appliances and other stuff picked up by the co-axial cable.

Kymmy

I aint got a clue where the aerial is what sort\type etc.

---------- Post added at 17:51 ---------- Previous post was at 17:51 ----------

You don't have any BBC channels duplicated do you? Some STB's if they see more than one transmitter can show the same channels twice, with the second version of the channel getting higher channel numbers.


Nope no duplicated channels either, just poor signal from all BBC :(

[multiskilled]

Do you know which transmitter you should be getting your signal from? Some freeview boxes tell you where it is receiving its signal from check it is the same on bbc channels as the others.

[swanee]

is it somethiing to do with bbc 1,2,3,4 sharing the same signal,making the reception poor?

[nodrogd]

Does anyone else on the system have the same problem, or is it just you. If it is the entire system then it could be either a faulty distribution amplifier or possibly swamping of the BBC digital channel by an adjacent analogue service.

[mattjtemp]

I'm having a bit of a mare, I've installed an ariel to the rear of my house, close to the roof.

The ariel is a SV9350 Outdoor DVBT Antenna, bought off Amazon

http://www.amazon.co.uk/exec/obidos/ASIN/B000TAWQT4/ref=ox_ya_oh_product

I tested the reception, got the channels I wanted, all looking good, then the next day all I can pick up is ITV3 and the shopping channels, a pretty ghastly choice.

The only physical thing I haven't yet checked, because it means borrowing the neighbour's ladder again, is the connection of the coaxial to to the antenna.

Is there anything else it could be before I go down that wobbly dangerous road again? As I said, the channels were working, the weather was clear, now it is overcast, it couldn't be that could it?

Any thoughts much appreciated.

[Kymmy]

Weather doesn't effect freeview frequencies as much as lets say sat freqs..

More than likely the coax has popped out of the connectors, the antenna/coa-ax join wasn't sealed up and has got waterlogged, or a strong wind/bird has knocked the antenna slightly out of alignment..

Also before you do anything check with a neighbour as it could be that work is being done at the transmitter...

But I will say that the antenna you bought is designed for minimal visual impact in a good signal area, or for example caravanners.. best to get a decent antenna something like:-

http://www.amazon.co.uk/SLx-27884D-Element-Digital-Aerial/dp/B000NH8516/ref=sr_1_6?ie=UTF8&s=electronics&qid=1255168053&sr=1-6

[nodrogd]

This is the problem when people first see digital TV. "Oh, you get a good picture here on freeview then! ".

It works perfectly until you reach the signal theshold, then breaks down very quickly. Go into the tuning menu and check the signal quality bar.

I'm currently working off an aerial that is the wrong group for all the digital channels in my area. Mux C and D work fine down to about 30% on the quality bar, but if it rains heavily or the birds congrigate on it, just a 10% drop results in a blank screen.

[mattjtemp]

Hi there,

thanks for the advice, I noticed ups and downs in signal quality over the weekend, so it is not really up to scratch.

I have cable downstairs and a 'proper' ariel on the main roof which is currently redundant, perhaps I should try connecting to that then?

What I do find baffling is that come what may QVC has a rock solid signal, why do the poorest channels do the best signal wise?

Anyway, thanks for the advice.

Matt.

[nodrogd]

Rooftop aerials are always best, so give the rooftop one a try.

Make a note of where the aerial is pointing and then look at Wolfbane's Coverage Predictor (http://www.wolfbane.com/cgi-bin/tvd.exe?)

Put in your postcode and from this you will be able to work out where you are receiving from and the size and group (Gp) aerial required. Then follow the link to the analogue coverage predictor. If the aerial group shows the same letter as the digital predictor then you should receive all the freeview channels available if the aerial is big enough. If it is different you will be in my situation of having a partial service.

The situation may change after switchover, so have a look at mb21's table (http://tx.mb21.co.uk/dso/rxaerials.shtml) to find whether the aerial will need replacing post DSO as regards the (PSB) public service and commercial (COM) mux.

[skalarocks]

I have been having the same problem with only the BBC channels for the last couple of weeks.
Freeview sent me the following info which might help: (check your transmitter for problems first).

The channels are broadcast in six groups, with each group on a different frequency, which is why you can get problems with a particular channel group, while other groups are unaffected.

This is most likely an aerial problem of some kind, whether with the
antenna itself, the cabling or connections.

We would recommend following this procedure to clear the memory of your
digital equipment and then rescan for the channels:

Remove the aerial from the equipment and leave unplugged.
Go to the set up menu and select rescan or retune to replace existing
channels. It’ll take a few minutes, but when it’s done, it should
say ‘'no channels found’.
Disconnect the equipment from the mains power supply and leave it
un-plugged for 30secs.
Re-connect both the aerial and the mains power supply and switch the
equipment back on.
Go to menu again and select rescan or retune. You should now have all
of the channels.

If this procedure does not resolve the problem, we would recommend that
you get in touch with the Confederation of Aerial Industries (CAI)
www.cai.org.uk or the Registered Digital Installers (RDI)
http://www.rdi-lb.tv/installers.html who can give you details of one
or more members who operate in your area and guarantee their work.

Sadly I cannot do all these checks myself as I am not in the UK and viewing the Freeview box via internet streaming. I have rescanned all the channels which I can do remotely but was not able to follow the instructions exactly.

Would be interested to know if this works for anyone else having this problem. It is definitely only BBC channels that I have a problem with.

[Chris]

Wow ... I'd love to know how that remote control and streaming set-up works!

[nodrogd]

Slingbox ??

[mattjtemp]

I have been having the same problem with only the BBC channels for the last couple of weeks.

Thanks for that, tried it, got the BBC back and lost Channel 4, not to worry, I will have to try and sort out another ariel.

The irony is agin, all the shopping channels are there, rock solid reception. Do I infer that low budget channels have more budget than nationals for transmitters or do I have to accept I live in QVC's demographic target areas!

[NeroAerials]

You cannot line up an aerial onto a digital signal accurately without a meter, even then, some installers, although they have tv meters are only able to locate the strongest signals, which are not alays the best, If asking for an installer, always ask if they have a spectrum analyser, that way they can show you every single channel working on their inbuilt screens to give you peace of mind, along with a one year, no quibble guarantee.

As advised above, please use a fully registered RDI who has been in the trade for a minimum 5 years as some of the newer ones, although they have the paperwork, still haven't got a clue what they are doing.

[Kymmy]

So anyone who hasn't worked for 5 years in the job is clueless??? Way to go in inspiring confidence in young and old people trying to learn the career.... :(

[NeroAerials]

Kymmy, I'm not saying that at all, but to be sure that you have someone doing your install actually knows what they are doing, then they have to be time served as well as have all the paperwork.

My boy has been doing it for four years, and even now he doesn't know everything, and he will openly admit it, and he has the qualifications to be an RDI as well, but then I also specialise in IRS systems (blocks of flats etc). and if you read what I said above, I did include the word SOME, I think we can all admit that there are some right cowboys out there, no matter what trade we are talking about. ;)

[Kymmy]

Yes there are right cowboys out there but your line is
please use a fully registered RDI who has been in the trade for a minimum 5 years

What about the poor guys who have the training and do actually know what they're doing.. Your lines says do not touch them as they're not part of the old firm :(

Yes there are some cowboys out there, but isn't it better to tell people to ask around, get recommendations from others and if you can't do that then ask the RDI as to who they recommend in the area (there's even a place on thier website for doing such a thing)

:(

[NeroAerials]

Kymmy, as a new member of the forum, I don't want to get into an argument with you, but let's just say that some of the people listed on the RDI site don't have a clue about how to put an aerial up shall we?

I can take it private if you want, but a lot of those on there who have 'employee of FLD' are completely unaware that they are RDI's, and in fact I know several of them personally who have never installed an aerial in their lives and actually pass any queries they have on to me.

[Kymmy]

So we should choose a member of the RDI even though the RDI register clueless people????? :confused:

[NeroAerials]

That is why I said in my opening post

You cannot line up an aerial onto a digital signal accurately without a meter, even then, some installers, although they have tv meters are only able to locate the strongest signals, which are not alays the best, If asking for an installer, always ask if they have a spectrum analyser, that way they can show you every single channel working on their inbuilt screens to give you peace of mind, along with a one year, no quibble guarantee.

That way, you can see the results for yourselves before the installer leaves your property, every registration scheme has it's faults, and this is a clear fault with the RDI system.

I'm just giving out advice, if people choose to ignore it, then that is their perogative.

[Kymmy]

:clap: At last a comment from a person and not a robotic antenna installer

You'll find that a lot of people on here like to do things themselves and not everyone has a spectrum analyser. Also an installer isn't always an option ;)

All we can do is give advice and possibly options as to what they can do and not what the must do :D

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