Help/advice from a TV aerial specialist please

Rapid 17

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I live in a flat and as far as I know am connected to a communal aerial shared with eleven other flats.
I mostly watch Freeview HD and record programmes onto a Freeview HD recorder. Up until a few months ago everything worked fine but then I started getting intermittent reception problems such as picture break up, blocky images, pixelation and an occasional no signal message.
An aerial fitter came and tested my signal last Monday and the signal was fine. I showed him the signal strength and quality on my TV, the strength was at maximum but the quality kept changing from high to low, he said this wasn't right and suggested It could be caused by 4G interference and he would make some enquiries on the subject and get back to me. At no time did he go and look at the communal aerial which I believe is in the loft of the building. A couple of hours after he'd left the problems were back again. I did some research on the net and found a company called at800, I requested a free 4G aerial filter which I fitted yesterday but it hasn't cured the problem. The lady at at800 said if it doesn't work a different filter may be required which would need to be fitted to the communal aerial. Are there other possible reasons for the problems I'm having ? should the aerial guy have checked the communal aerial ?
All comments or suggestions/advice will be gratefully received.
Many thanks.
Geoff.
 
Try fitting a variable TV attenuator. The signal level could simply be too high and is overloading the Freeview tuner.
 
Also check for HDMI interference which is a common cause of the symptoms you describe.

If you are using an external Freeview HD recorder that means you must have at least one HDMI lead going from it to your TV. (... possibly more if you have other HDMI connected equipment.)

HDMI leads can leak RF which interferes with the incoming UHF on aerial leads and can cause the reception problems you are seeing.

The remedies for such problems are: Keep HDMI and aerial leads as far apart as possible. Try other HDMI leads.
Consider better screened UHF leads. Make sure all connections are clean and well made - including incoming aerial wall outlets, if used.
 
Have you spoken to other residents on the same communal system? If they also have problems you need to speak to your landlord.

Unlikely to be overloading suddenly unless someone has been fiddling with an amplifier.

4G interference, though possible, has been grossly exaggerated.
 
Have you spoken to other residents on the same communal system? If they also have problems you need to speak to your landlord.

Unlikely to be overloading suddenly unless someone has been fiddling with an amplifier.

4G interference, though possible, has been grossly exaggerated.

On what do you base your opinion ? Suggest you do some research. Anyone who reports 100% signal level post DSO is likely to have issues. (an immediate alert as to the issue). I don't know what kit the OP is using, but if it's a Humax box, knowing most of them have sensitive tuners that work really well in weak signal areas, it's a very common issue, easily solved by attenuating the signal.

Only the OP can say if that is the solution.

Frankly your post does not add anything here.

Unlikely to be be 4G ?

Unlikely to be signal overload ?

No comment re HDMI interference (which generally only affects 1 or 2 MUX)

Can I ask what your post adds to this thread ?
 
I base my opinion on experience. The OP said it was OK until a few months ago, well after DSO when the problems you suggest would show up, so yes unlikely to be signal overload. The HDMI issue had already been brought up so no need for me to mention it again.

As far as 4G is concerned AT800 has already sent out filters to affected areas, and as the OP said a filter did not help anyway.

With problems on a communal system the first thing to do is to check with other residents to ascertain whether it is the system at fault or something in your own residence. Overloading (or any other fault) on a communal system should be corrected at source not in individual flats, as when the fault is fixed later at general maintenance the flat owner will suddenly find himself with too little signal.

So DO NOT go around criticising other members posts. To do so does not help the OPs problems at all.
 
Whilst I tend to agree with winston's comments, I also agree with GLT about the signal strength thing, as the OP is suffering the possible symptoms of either too much signal or co-channel interference (CCI). I have suffered both. The first was caused by a high gain masthead amp (MHA), coupled with the gain of my distribution amp. Fixed by removing the MHA. The second, I have not been able to do anything about. The symptoms for the first was high sig strength (on the sets) and quality dropping to zero as the RF front end could not cope with the large signal. The second (after removal of the MHA to eliminate too much signal), I cannot fix, again the quality drops to zero, i assume that's when the error correction cannot cope as the pre viterbi error rate starts climbing then the post viterbi error rate shoots up with corresponding blocking and picture loss.

Having said that, I strongly agree with winston re. asking other tenants if they have the problem, and Gav's comments about HDMI leads, and also wonder if the OP has done the good old switch it off, wait a while then switch it back on trick. (Unlikely fix, but worth a try)
 
I base my opinion on experience. The OP said it was OK until a few months ago, well after DSO when the problems you suggest would show up, so yes unlikely to be signal overload. The HDMI issue had already been brought up so no need for me to mention it again.

As far as 4G is concerned AT800 has already sent out filters to affected areas, and as the OP said a filter did not help anyway.

With problems on a communal system the first thing to do is to check with other residents to ascertain whether it is the system at fault or something in your own residence. Overloading (or any other fault) on a communal system should be corrected at source not in individual flats, as when the fault is fixed later at general maintenance the flat owner will suddenly find himself with too little signal.

So DO NOT go around criticising other members posts. To do so does not help the OPs problems at all.

It's possible that the signal gain has been increased possibly resulting from a complaint of weak signals on a different user further from the dish than the OP.
 
It's possible that the signal gain has been increased possibly resulting from a complaint of weak signals on a different user further from the dish than the OP.

I covered that in post 4 when I said,

"Unlikely to be overloading suddenly unless someone has been fiddling with an amplifier".

Of course a half decent engineer would check overall performance to all tenants before fiddling with amplifier gains.

I think we need to wait until the OP reports back about the other tenants before we speculate further.
 
I covered that in post 4 when I said,

"Unlikely to be overloading suddenly unless someone has been fiddling with an amplifier".

Of course a half decent engineer would check overall performance to all tenants before fiddling with amplifier gains.

I think we need to wait until the OP reports back about the other tenants before we speculate further.

Basically anyone who reports 100 % signal strength without quoting signal quality is a prime candidate for signal overload. Of course this varies with individual kit. With my Humax kit my weakest MUX is less than 50% signal but 100% quality. Reception is 100% solid.

Basically a cheap attenuator is a no brainer to check if this is the issue. I have a few in my toolkit. Suggest you get some as well :eek:
 
100% signal level is meaningless. 100% of what? No one tells us and different receivers give different levels anyway.

I do have some attenuators in my kit, but I really can't remember when I last needed to use one, and I've been in this game over 50 years.

Edit, just remembered when I needed one, it was in 2004 when I moved into my present house. Around 90dBuV off the roof aerial on analogue channels. Lobbed in an 18dB attenuator fixed it. Later replaced it with a 3dB one followed by an eight way splitter fed to various rooms. Perfect reception at all points.
 
Thank you for the replies everyone, I haven't had time over the weekend to act on the suggestions apart from ordering a variable attenuator which I'll fit as soon as it arrives and hope it solves the problem.
Today I plan to ask other residents in the block whether they've also had problems with Freeview HD. I did asked the management company a while ago whether anyone else had contacted them with the same problem but was told I'm the only one.
Once again, thank you for your help/advice, it's very much appreciated.
Geoff.
 
Update.

I've fitted a variable attenuator and reduced signal strength to 52/100. Signal quality still varies between 100 and lower numbers but so far I've had no more picture break up.
 
Today I plan to ask other residents in the block whether they've also had problems with Freeview HD.
Well, did you? And if so, what was their answers?
 
Update.

The management company had a new Freeview communal aerial installed on July 7th, the reception recently has been extremely bad from this aerial.. I suggested they contact at800 and request a 4G filter suitable for communal aerials. The following is the reply I received.

I have spoken to the aerial installer and he informed me that a 4G filter is not needed, as there is a Launch Amplifier in the loft already.


The new Freeview Aerial that has been installed will have improved the signal strength by approx 20%

What do you guys make of that ?


I'm currently looking at the signal strength and quality on my TV, strength is static at 97% and quality is constantly changing from the 100% maximum down to 52%. On other occasions the quality has gone much lower than 52%.
 
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Several people have told you to check with other tennents. Have you?

As for you asking the management company to ask AT800 for a filter what makes you think that you know better than the aerial installers? I imagine the launch amplifier already has an internal filter.

4G interference is very rare, I think someone told you that also.

So check with the other tennents.
 
Several people have told you to check with other tennents. Have you?

As for you asking the management company to ask AT800 for a filter what makes you think that you know better than the aerial installers? I imagine the launch amplifier already has an internal filter.

4G interference is very rare, I think someone told you that also.

So check with the other tennents.

With respect Nathan, I don't know or pretend to know better than the aerial fitter, I've no idea what a launch amplifier is that's why I'm seeking advice and opinions on this forum.
You state 4G interference is very rare, if that's not the cause of the problem what else could it be ?
Regarding asking other flat owners and tennants, I asked one and was told they'd not had a problem. I then posted a note on the notice board just inside the main entrance door asking whether anybody had been having problems with Freeview reception and to contact me if they had to discuss the matter but no one did. I also contacted the management company to see whether anybody had reported a problem, again no one had.
Also, I have friends who live in a bungalow at another part of the area, they have a roof mounted aerial and have recently been having similar problems with their Freeview reception even with a 4G filter fitted.
 
Presumably you have tried fiddling with your variable attenuator to no avail?
 
You state 4G interference is very rare, if that's not the cause of the problem what else could it be ?
Regarding asking other flat owners and tennants, I asked one and was told they'd not had a problem. I then posted a note on the notice board just inside the main entrance door asking whether anybody had been having problems with Freeview reception and to contact me if they had to discuss the matter but no one did. I also contacted the management company to see whether anybody had reported a problem, again no one had.

So it's not 4G, and it's not the communal system. Time to start checking your own equipment.
 
So it's not 4G, and it's not the communal system. Time to start checking your own equipment.

It's definitely not my equipment, the TV I owned when this problem first reared it's ugly head was a Sony Bravia KDL-55W29 purchased in March 2015, that TV I gave to my daughter and she watches Freeview SD and Freeview HD on it without any problems. In fact I was at her house this morning baby sitting and the picture quality was superb.
My current TV is a Panasonic TX-65DX902B purchased in April 2017.
 
Presumably you have tried fiddling with your variable attenuator to no avail?

Thank you for your reply, I've tried the attenuator on the previous aerial but not yet on the new one. I'll give it a go this afternoon.
 
It's definitely not my equipment, the TV I owned when this problem first reared it's ugly head was a Sony Bravia KDL-55W29 purchased in March 2015, that TV I gave to my daughter and she watches Freeview SD and Freeview HD on it without any problems. In fact I was at her house this morning baby sitting and the picture quality was superb.
My current TV is a Panasonic TX-65DX902B purchased in April 2017.

So it is not your TV. Your equipment includes the leads and anything inline with them. Have you checked those. Try a new lead between the wall point and TV with nothing inline.
 
I'm currently looking at the signal strength and quality on my TV, strength is static at 97% and quality is constantly changing from the 100% maximum down to 52%.
Classic symptom of signal strength too high for your equipment*. Since your attenuator fixed it previously, it seems that you now need to add even more attenuation. Is your dwelling the closest to the launch amplifier? It sounds as if the wrong attenuator tap has been installed for you - assuming that there is one.

*However, other causes are possible.

I don't understand why your building management committee can't simply arrange for an installer with the necessary equipment to visit your dwelling. That would eliminate all of the guesswork.
 

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