Freeview Picture Breaking Up

O

organica

Guest
Hi folks -

I'm fairly clueless about Freeview, don't even have a television. I just got my Dad a DVD recorder w/ freeview (Panasonic DMR-ES20) and he is having intermittent trouble with the picture from it (i.e. the direct reception rather than recorded material), and wondering if he needs to take it back to the shop. The manual for the ES20 seems to have approximately zero info about the built-in freeview receiver, so no help there.

The interference is not lines or artefacts on the screen, it's more time-based, the picture and sound will kind-of jitter in and out or "hang" before continuing. This only occurs on certain channels - BBC 1, 2, ITV1, Ch4, Ch5 are all fine. The problems seem to occur with channels like 18-22, and some further on - when I tried accessing them via a dedicated freeview box, it just seemed to skip these channels completely.

From this I'm guessing that the problem is not with the unit, but with the signal reception - but before I start reading up on that and messing around with it, I just wanted a second opinion.

In terms of setup, he is using an internal loft aerial that has always been fine for analogue from the same transmitter, but I guess digital may be more demanding in some respects? There is only one TV socket in the house AFAIK. I checked the reception lookup at www.dtg.org.uk, and it is just a long line of YESses for his post code. So my thinking is he needs to get an external roof aerial, or perhaps some sort of booster box.

My Dad is pretty happy as he gets nearly all the channels he's interested in - all he really wants to know right now is whether there might be a fault with the Pana...
 
From what you are saying it all points to the need for a new aerial, Freeview boxes often give you the signal strengh on the screen (well it does on mine) as you change channel and unless it is consistantly over 80% then that is a weak signal.
 
The symptoms you describe are typical of bad digital reception. The power used for digital transmissions is lower than for analogue, and, for many transmitters, the UHF "channel" numbers (i.e. frequencies) are outside the range covered by many standard aerial installations. As Andy says, the only cure is a better aerial installation, including, usually, better downleads; consult a CAI installer in your area.
 
Andy, Nigel, thanks for that.

I've now got a list of CAI installers for my Dad's area, and I've passed that onto him.
 
I have a Toshiba 32WLT66 with built in Freeview and I have noticed the picture breaking up whilst sending and recieving text messages on a moblie phone. It also does this every 10 mins or so when the phone must send out a signal of somekind? If I turn off the phone, no problems!

Anyone else noticed this?
 
The frequencies used by the upper part of UHF Band V are not far below those used for some GSM phone services.
I wonder if it only happens when you're watching Freeview ; if it also interferes when watching a DVD (or other external A/V source), see if it disappears when the aerial is unplugged.

Chris Muriel, Manchester
 
I have an interesting addition to the issue of a broken picture on a digital box.

Whenever a pizza scooter or similar passes by the house, the picture breaks up for a good 10-15 secs. Has anyone else experienced this strange phenomena??
 
Not really that surprising.

Many poorly-maintained vehicles have badly suppressed ignition; this causes RF impulse interference. The same can be true of pretty much anything electrical; thermostats (on central heating or refridgerators, for example) and so on.

On an old radio, you'd get a crackle; on analogue TV you'd get some sparklies and/or a crackle. On digital TV you get blocking and freezing. Different symptoms, but the same cause.

And your own aerial wiring is probably contributory. If you have either a weakish signal from the aerial and/or a poorly screened downlead, your digital signal will be more probe to errors caused by such interference.
 
street lights another good one-i had to get the council to replace one right next to the house as it caused blocking etc when ever it came on!!
 
organica said:
In terms of setup, he is using an internal loft aerial that has always been fine for analogue from the same transmitter, but I guess digital may be more demanding in some respects? There is only one TV socket in the house AFAIK. I checked the reception lookup at www.dtg.org.uk, and it is just a long line of YESses for his post code. So my thinking is he needs to get an external roof aerial, or perhaps some sort of booster box.

My Dad is pretty happy as he gets nearly all the channels he's interested in - all he really wants to know right now is whether there might be a fault with the Pana...

If the internal loft aerial has been there for some time it is quite possible that it was a narrow band aerial which was fine with analogue tv which tended to broadcast across a narrow band of frequencies (to avoid interference between neighbouring regional transmitters). Digital requires a wide band aerial although it uses no more "channels" (muxes) - it has had to fit in alongside the analogue channels and has spread further across the whole frequency band. In my area analogue is between channels 43 to 60 whereas digital is across chammels 21 to 64. The colour of "bung" in the end of reasonable quality aerials usually indicates what band the aerial is for (black is wideband):cool:
 
davemurgatroyd2 said:
Digital requires a wide band aerial
That depends on the transmitter. It's true for many, but not all.
davemurgatroyd2 said:
it uses no more "channels" (muxes)
Analogue TV is 5 UHF "channels". Freeview uses 6 UHF "channels". Any given transmitter transmitting both is therefore transmitting on 11 UHF "channels".
 
Further to this - passed the info on to my dad, but he is slightly reticent about having 3rd parties mucking about up on his roof, and he's wondering if there are any steps he could take to improve the situation himself - for example, taking the existing aerial and fixing it outside, changing the aerial angle, getting some kind of internal booster box etc.

The existing aerial was fitted - literally - about forty years ago, and as we are fairly near the transmitter, the installation probably didn't need to be all that stringent - it's just laid across rafters on the loft.

I have warned him he possibly needs a more specialised aerial before he can get some of the channel bands - but are there any simple steps we can take with a view to improving matters, before him biting the bullet and getting a bloke up on the roof?
 
40 year old antenna equals replacing it...Especially for the cabling alone, the screening on the old, probably brown cables, was pathetic compared to what is used today...That should help quite a bit with the pizza delivery scooters as well....

Our antenna was about 20 years old (and the cabling), I was able to get all muxes (and thus channels) but every now and then I'd loose some...Replaced the antenna recently and are now in Freeview bliss...Works really well, no interference or anything....Well worth it...

Oh and as LV stated, don't assume you need a wideband, you may live in an area where it would have the adverse effect. Any CAI installer would know that....But if you dad wants to do it himself, there is a site and I can't think of it anymore which states what type of antenna you need depending on the transmitter you want to receive....But to be honest I would just spend the extra £30-60 quid to get a professional to install it as with respect some of the questions are basic and you want to ensure the right cabling, termination, antenna, direction, height, amplification, attentuation, distribution, etc...is being applied....
 
I recently purchased a JVC 37" Freeview equipped LCD and the picture quality was terrible compared to my previous Samsung.
I got a local guy in who fitted a new high gain aerial and cables and it has improved beyond all recognition.
He was going to charge me £100.00 fully inclusive but I went for a better quality aerial than the one he would have fitted as standard so it cost me £130.00 all in.
Well worth the money in my opinion.
Rob
 
I have some old cable fitted to mine( at least 20 years old) and the screening is really good much better than cables today,saying that i don't need much of a signal here and i would need a good quality sat spec cable to better it.
A change of aerial and cable would work wonders though in this case.
 
As I mentioned in another thread, I've had a 'Road to Damascus' experience with a £10 aerial amplifier from Argos...

There is a lot of ****** being talked about aerials at the moment - mostly by aerial installers...:devil: Here's my experience:

I have a £8 wilko TV aerial at half house-height in Swindon pointing at Mendip through a tree!:)

My postcode is listed as "marginal" and "Will need high-gain aerial" in the freeview reception website.

My S/N ratio on my cheapo Daewoo freeview box was 19db (marginal). My freeview would break up on wet days.

After installing the £10 aerial amp - S/N ratio increased to 24 db (rock solid)
and my freeview never breaks up.

So ... before anyone considers an aerial upgrade they should buy an 'in-room' aerial amp from Argos and try it ... Argos will take it back if it doesn't improve matters.
 
p0l0nium said:
As I mentioned in another thread, I've had a 'Road to Damascus' experience with a £10 aerial amplifier from Argos...

There is a lot of ****** being talked about aerials at the moment - mostly by aerial installers...:devil: Here's my experience:

I have a £8 wilko TV aerial at half house-height in Swindon pointing at Mendip through a tree!:)

My postcode is listed as "marginal" and "Will need high-gain aerial" in the freeview reception website.

My S/N ratio on my cheapo Daewoo freeview box was 19db (marginal). My freeview would break up on wet days.

After installing the £10 aerial amp - S/N ratio increased to 24 db (rock solid)
and my freeview never breaks up.

So ... before anyone considers an aerial upgrade they should buy an 'in-room' aerial amp from Argos and try it ... Argos will take it back if it doesn't improve matters.

As An Aerial Installer Ill Admit Around 30 % Off The Population Are Managing Fine With Low Cost DIY Rigs How Ever The Scope Of Digital Will Only Get Bigger And The Faults Even Larger. You'll Notice On Most Posts There Is Only Problems On A Few Channels this is common with normal terrestrial aerials as they are grouped and one MUX (group off up to 10 channels) will be outside the design of the aerial here lies that fault.. main other faults are EMR (electro magnetic Radiation) This Occures When Poor Or Old Cables Over As Young As 5 years Are Poorly Screened We All Have Bluetooth On Our Phones Wireless Broadband Microwaves And The Main Killer FM.

Trust Me When I Say A New Aerial Will Cure Your All Those Fault And In My Region still one of the chepest £70 Will Get You A Med Quality QR10/18 Digital Aerial, Brackets, Mast,Best Coaxial, Information And A £100 If Amplification Is Needed. But Most Off All In A Years Time When The Bandwidth Is Increased And The Wireless Advancments Develope Twice Fast The Idiot Going To Argos For His Soulution Will Be Calling An Expert To Fit A Rig That Will Last Many Years
 
p0l0nium said:
As I mentioned in another thread, I've had a 'Road to Damascus' experience with a £10 aerial amplifier from Argos...

There is a lot of ****** being talked about aerials at the moment - mostly by aerial installers...:devil: Here's my experience:

I have a £8 wilko TV aerial at half house-height in Swindon pointing at Mendip through a tree!:)

My postcode is listed as "marginal" and "Will need high-gain aerial" in the freeview reception website.

My S/N ratio on my cheapo Daewoo freeview box was 19db (marginal). My freeview would break up on wet days.

After installing the £10 aerial amp - S/N ratio increased to 24 db (rock solid)
and my freeview never breaks up.

So ... before anyone considers an aerial upgrade they should buy an 'in-room' aerial amp from Argos and try it ... Argos will take it back if it doesn't improve matters.


What signal booster did you get ??
 
1st Digital said:
As An Aerial Installer Ill Admit Around 30 % Off The Population Are Managing Fine With Low Cost DIY Rigs,,,

I am sure you have a lot of knowledge to share but it would be easier to read it if you did not capitalise almost every word. It would probably be quicker to type as well. :D

Richard
 
Actually, I don't even find it amusing. The typing is REALLY hard on my eyes. Is it meant to be a joke? Why not just type normally so we can understand it?
 
Thanks for the replies folks -

(posted this a for my Dad a few days ago, then promptly forgot all about it :suicide: )

I'm just geting a big row of yesses, and
Muxes received: ALL
Compass bearing: 75°
Distance: 21 kilometres
Aerial group: E/W Horizontal
Location: Grid Ref NS828647
Aerial elevation: 556 metres

I don't really have a point of reference for these figures, but our analog reception has always been great, as we are quite high up, and can probably see the transmitter from our skylight on a clear day...

The Argos route is really what I'm looking for, as my Dad wants to test out a solution that doesn't involve someone going up on his roof...

p0l0nium, could you tell me what signal amp you got?
 
I live on the Thames, and every time a boat goes past I get interference on a few weak channels. Especially rickety old party boats or hard core tugs.

Might be something to do with my temporary aerial... The steel trunking behind the TV...

286864650

http://www.flickr.com/photos/94926675@N00/286864650/
 
As a follow-up to this, we tried out all three signal booster available from Argos - in the end, the cheapest of the three proved most effective. But still a few of the channels aren't quite getting the signal strength. The aerial orientation seems about right going by the stats.

We're going to go up and mess about with the orientation and see if we can improve matters - if not, perhaps an outside aerial will be the final move...
 

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