Freeview intermittent interference
Brian Butterworth published on UK Free TV There are several different types of interference that cause problems. This page deals with the situation where:
- Freeview reception is perfect or near-perfect most of the time
- The audio on TV and radio channels mutes momentarily a few times each minute
- The picture on a Freeview channel freezes a few times each minute
There are two main causes of this type of intermittent interference:
- 'Induction' interference
- Mobile phone interference
Induction interference
Induction interference is caused by mains-powered household devices that contain a large motor, such as:- Washing machine;
- Tumble dryer;
- Central heating pump or combination boiler;
- Fridge;
- Freezer;
- Power tools (drills, jigsaws etc)
- Vacuum cleaners;
- Water pumps;
- Automatic doors
You can identify if one or more of these devices is causing the Freeview reception problem by powering off the devices.
If one of these devices is causing the problem, then the reception problem can usually be solved by using a mains filter device and use it on the Freeview boxes mains connection.
Such as device is this: Maplin: 6-Way Flat Screen and HDTV Surge Protector and Mains Filter.
Mobile phone interference
If you keep a mobile phone by your Freeview box or digital television, keep it further away!This also applies to other transmitters such as baby monitors, video senders, walkie talkies, and portable phones.
Help with Freeview, aerials?
Wednesday, 1 November 2017
R
RDD12:02 AM
Stansted
CM24 8DL postcode. Gable end aerial. Wide band, mast head amp. Crystal Palace Transmitter, Mobile masts due south 1 Km Tall trees due south 0.1km
Current aerial need replacement. Normal non HD channels normally good strength (60%).. HD channels poor
However this evening normal channels no signal to very poor. No CP engineering reported .
A) atmospherics??
B) In choosing new aerial , with coming changes 2018, what should I go for ?? Log periodic A ??
Thanks
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RDD's: mapR's Freeview map terrainR's terrain plot wavesR's frequency data R's Freeview Detailed Coverage
MikeP
6:25 PM
6:25 PM
RDD:
Looking at the Freeview coverage map and the digitaluk trade pages from the links below your posting, it appears that Crystal Palace is the better option to use.
It could be that some atmospherics are causing problems as a number of people around the country have reported similar to you, but none have had any current engineering work. Ask your neighbours if they are having the same problems, but make sure they are discussing Freeview and not Sky or Freesat via a dish.
As for future-proof aerials, always look at having a good log-periodic type installed. They are not specific to any of the traditional aerial groupings as they are wide band designs. The only consideration for you is whether a 36 element is enough or to go for a higher gain type with more elements. I use a Log36 (see ATV`s Choice Of Aerials for digital TV and it wirks very well. You may need an amplifier in conjunction with it as you already have such a device fitted.
The objective is to have signal strengths of between 50% and 85% for SD channels and between 60% and 85% for HD services. The current Com7 and Com8 multiplexes are due to be phased out from around 2020 and more multiplexes will use DVB-T2 encoding, meaning it will need the use of a Freeview HD TV set (not just an HD Ready one which will not have a DVB-T2 tuner).
Hope that gives some ideas?
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Thursday, 2 November 2017
R
RDD1:18 PM
Stansted
MikeP:
Thanks for the feedback.
Still had problems later that morning, vast majority of channels 0%. Signal matters resolved by a) blank (aerial unplugged) re-tune followed by aerial in retuning both HDTV and DVR. Not sure whether "atmospherics" miraculously righted themselves in the 20 or so minutes taken to carry out the procedures, OR whether something caused the tuning to go out ( aerial/mastehead amp wise) Had checked power supply to masthead amp and was OK.
Anyway sorted for the moment, if anything signal stronger ;).
Re new aerial, will take your suggestion re long log periodic, as it will have far less wind drag factor than the "Chip Pan" Televes wide-band I have at the moment, that has started to fall apart after many years use. The local pigeons appear to use it as a copulation point!!
Will also look out for an LTE version of of the LogP as mobile masts have started to accumulate in some ground nearby ( <1 km)
Thanks again for your help.
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RDD's: mapR's Freeview map terrainR's terrain plot wavesR's frequency data R's Freeview Detailed Coverage
MikeP
11:51 PM
11:51 PM
RDD:
Please read Freeview blames air pressure for TV disruption - BBC News whwrw Freeview categorically state that it is due to the high pressure.
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Friday, 24 November 2017
K
Kay Coleman12:45 PM
Heanor
This is my second post here. Back in September, I abruptly began getting terrible reception on Freeview, when it had worked perfectly up to then. I tried everything, to no avail, but, after almost a week, it resolved itself, & had been ok since then. I still got the occasional "flutter", but I could live with that. However, now it has happened again, & seems even worse this time. Everything was working well, until, 4 days ago, when the picture suddenly began to break up, & got progressively worse, until it was rendered unwatchable. As before, only ITV has remained stable, but this time, even that is bad sometimes. On all other channels, the picture is heavily pixelated, constantly freezes, makes loud buzz-pop sounds, & the "No or bad signal" thing appears repeatedly. Once again, I have tried everything, all the recommended fixes, & even done a factory reset, but nothing helps. What does not make sense is that the reception improves late at night, & in the early morning hours, when it can be quite good, but come around 6:00am, the gradual degradation begins again. I have checked, & there are no transmitter problems reported here. According to the tracker, the mast I receive from is Emley Moor, although I am in Derbyshire, & a short distance from the Nottingham border. (my postcode is DE75 7EX). When I first rescanned my STB, it said there were region conflicts, & I found was a better signal from Yorkshire. When I scan now, it just runs through, & goes straight to Yorkshire, & not given the choice between that & Central, as it did before. I am at my wits' end here, nothing I have tried works, & I am fresh out of options now. I cannot understand why it suddenly deteriorated. I live with relatives who have Sky in the living room, & 4 other HD TVs with built-in Freeview, while my TV is the old style, (with the big back), & I do not think it is HD compatible. My STB is a standard digital. All the other TVs in the house are working well, with perfect reception, so there is no problem with the aerial.This makes no sense. Up until 4 days ago, I just took it for granted that I could turn my TV on, & watch my favorite shows, but now I have to attempt following in snippets, between break-ups & freezing. Any advice would be greatly appreciated.
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Kay's: mapK's Freeview map terrainK's terrain plot wavesK's frequency data K's Freeview Detailed Coverage
M
MikeB10:09 PM
Kay Coleman: Check that your actually tuned to Emley Moor - Digital UK reckon thats your best bet, and at 69km, not too far away. If your set has picked up another transmitter (like Belmont), then your signal might be too low.
Next, check your signal strength on each mux (or group of channels). If they are low to non -existent, then check your cables. If its too high (90%), then thats solvable.
Start with the one from the back of the TV and trace back the signal - if the other TV's in the house are fine (and they are fed from the same aerial, not on Sky), then its likely to be between the point where the signal is split and your TV.
No, an old deep TV is not HD, but you can check quite easily if its the box, the cable or the cable from the ariel to the wall - take the box and lead from the TV, and use them in another TV. Connect the box to the TV via a scart and the aerial lead that your using. If its all fine, its likely to be the wall fitting with your TV or the lead from the aerial to it.
If there is a problem, then its the box or the lead. So change over the lead to one that you know works.If it then does, you've answered your problem.
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Sunday, 3 December 2017
K
Kay Coleman4:54 PM
MikeB: Thankyou for your response & assistance. As far as I know, I am tuned to Emley Moor, as all the local news channels & weather reports are for the Yorkshire region. I have no other way of knowing. When I moved here from the US 5 years ago, my brother set up the Freeview box, with the TV. For a few months, all was well, but then I started getting serious reception problems. I performed a scan, & at the end, it stated that there were regional conflicts, & gave the choice of Central or Yorkshire. I had been on Central, so I tried Yorkshire, & that immediately fixed the problem. Now, when I have done further scans, I think it goes straight to Yorkshire. When it completes the scan, it just says "Flash saved successfully", & goes back to the channel it was previously tuned into. I feel I have tried everything, but it just seems to be getting worse, & my reception is now so bad & corrupted, it is virtually unwatchable. Now, along with the "No or bad signal" box constantly appearing, sometimes it says "HD TV is not available", when neither my TV or STB are HD. Strangely, though, for a few hours in the early mornings, from around 1:00am, I can get really good reception, until around 6:00am, when the degradation begins again. Initially, the problem abruptly occurred while I was actually watching TV, the picture began to suddenly break up, & has not recovered, & it has been almost 2 weeks now. I am sure the TV & the STB are ok, or it would be bad all the time, with no early hours respite, when everything can be perfect. My aerial cable leads through a hole in the wall, into the master bedroom, where it shares a splitter with the TV in there, which has perfect reception. We tried swapping the connections, & that did not help. Yesterday, I tried another aerial cable we know is good, in my STB & TV, from a good connection in another room, but that was still to no avail, the reception was as bad as ever, so it cannot be my cable at fault. I have checked my signal strength on the channels, & they are all very low. I cannot understand why only my TV is affected. All the other TVs in the house have perfect reception, while mine is totally messed up. I just want to be able to watch TV again, something everyone else I know takes for granted, & I can't. This is so frustrating, there must be a reason, & some way of fixing it.
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Tuesday, 5 December 2017
K
Kay Coleman5:16 PM
MikeB: I think my problem is beyond help, for the last couple of days, it has been bad on all channels, even ITV is messed up, with no early hours respite now, anywhere. Has progressively worsened, & nothing seems to work towards fixing. Must be gremlins at work :(
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MikeP
5:31 PM
5:31 PM
Kay Coleman:
Your problem is not beyond help as long as you perform the checks being advised.
We need to know what the signal strengths are for all the multiplexes from Emley Moor and that you are tuned correctly to that transmitter. It is only 69km away and you should have perfect 'line of sight' towards it.
That suggests you have a problem with your aerial system and/or its connections to your TV set.
So please check all the coaxial cables, plugs and connections between the aerial and the set. Then check that you are correctly tuned to the correct channels from Emley Moor - the correct channels to use are listed at https://ukfree.tv/transmi…oor. Then check the individual signal strengths for each of those channels and report them back here. Your User Manual for the TV sert will tell you how to show the strengths and quality details, usualy found on the Manual Tuning page - but do *not* perform any tuning.
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M
MikeB7:18 PM
Kay Coleman: Ok, I think I know whats happening.
I assume that the 'digibox' is an HD box or PVR, since it would be pointless to have a Freeview box when your TV already had one.
It sounds like its been 'looped through', which is standard, and which should work if the box is off. But yours hasn't been set up properly, and you need to go to the setup menu, and find the part which tells the box to carry on passing through the signal when its on standby. It should show you in the manual, but you probably wont even need that.
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