Where is the interference to my Freeview service coming from?

Where is the interference to my Freeview service coming from?

^{Brian Butterworth published on UK Free TV 2nd October 2014 at 08:14}
My queery relates to signal interference. My address is in the exmoor region and according to your web site our signal would most likely be coming from the stockland hill transmitter. Most of the time our signal is good but occasionally we loose the independent TV stations such as ITV1 or 2. Using the 'technical info' menu on our sony digibox it shows that the signal strength is ok but that the signal quality is lost. Therefore this would suggest to me that there is a source of interference somewhere. Can you suggest any likely causes in this instance or is there anything we can do? Currently we would not be able manage without our analogue signal!!

Multiplex 2 (Channel 4, CITV, E4, itv1, ITV2, itv3, itv4, More4, TeleG, Teletext, Teletext Holidays, Teletext on 4, Teletext TV Guide) is transmitted on C28 (530MHz) from Stockland Hill.

The most likely explanations for interference are from a device with an RF output such as a VCR, Sky Digibox or a games console.

Another possible is that the 64QAM mode that is used for multiplex 2 is the problem. This would certainly be the case if you have a loft-mounted aerial.

https://ukfree.tv/article/1107051058

We do not have a games console or a sky digibox and our VCR is never in use when we get this interfered signal. It is definitely the channels that you have listed that are subject to the interference, possibly suggesting that the 64QAM mode is an issue.

We are in a low lying area, therefore we have a high roof mounted aerial with a booster box fitted, which like I say produces an excellent signal most of the time, which can very suddenly break up completely (not weather dependent).

Could it possibly be a neighbours electrical appliance? For instance a VCR etc that may be positioned the other side of an adjoining wall where our TV/digibox is positioned. Bearing in mind our walls are made of stone no less than a foot thick!

If you feel that this is unlikely how might we go about contacting the multiplex 2 channel broadcasters to voice our concerns, especially now that the date for analogue switch off is getting closer.

Your VCR doesn't have to be in use to cause interference, it would simply need to be powered on. If the VCR is in any way connected to the same aerial source as your Freeview box it will cause a problem.

Electrical appliances certainly do cause Freeview reception problems, but this tends to effect all channels and results in momentary picture break up. The usual causes are washing machines, central heating boilers, fridges, freezers. This kind of interference can be eliminated using a mains suppressor (or filter).

This type of interference is carried by the mains cable, so it is not the proximity of the device, just that it is in the same property. Normally your neighbour's supply will be on a different 'phase', so it probably not going to be them!

Is your booster located on the aerial (a 'masthead amplifier') or located somewhere else? Some boosters are not Freeview compatible and you can sometimes get a better signal by disconnecting them.

Another source of interference to digital terrestrial signals is GSM mobile phones if they are placed next to the set-top box or aerial.

If it were to be VCR interference I gather from what your saying is that it would affect all channels? What I will perhaps do is bypass and unplug the VCR when we experience this problem and see what happens. Is this a logical idea? Failing that can I raise my concerns with the multiplex 2 broadcaster? Do you know if there is a web address etc?

VCRs usually output the TV picture on a single RF channel, and thus tend to effect only a single multiplex's reception. This is in addition to the unmodulated output you get by using a SCART cable. Most people don't use their VCR's RF output facility. If you disconnect it and this resolves the problem for multiplex 2 reception, then you can usually change the RF channel used, usually by twisting a connector on the back of the VCR.

3/4 Ltd is not a public facing company, but you can call ITV on 0121 634 4402.