Griffs Posted October 5, 2004 Posted October 5, 2004 Hi I have been experiencing a break up of picture (horizontal bands of pixelation) when washing machine cycles, fridge door opened, light switch operated etc. Had electrical system checked out OK by two electricians. Ran Plasma screen and Digital tuner off portable generator with a temorary aerial run over the side of the house (to eliminate house electrical wiring and existing aerial run) and still experienced interference. Had aerial run checked out OK but still upgraded aerial cable, interference still there. As last resort changed combination TV aerial to a VHF high gain aerial, and tried positioning it at various positions on roof, still no improvement. Finally put the VHF aerial on as high a mast as I could get on the roof (5m?). Picture break up reduced but is still there. Switching noise causing interference that is reduced the further the aerial is placed from the source of electrical switch noise. Switching noise effects some channels more than others. Can anyone provide a solution to problem?
anthonysimilion Posted October 5, 2004 Posted October 5, 2004 I find it is common to have some interference when some electrical devices are activated such as light switches (fridge door opening operates a light switch). Some models of washing machines have more issues than others.
alanh Posted October 5, 2004 Posted October 5, 2004 Griffs, I have answered this question many times. The answer depends on where you live. Check out your geographic forum. Search posts by AlanH. If the answer is insufficient, then ask your questions on that geographic forum. AlanH
Digicruiser Posted October 6, 2004 Posted October 6, 2004 It may pay to summarize here what to do anyway... I had a sparking washing machine which did not once break up my picture after doing these things; of course the occasional plane or helicopter and very strong source still can break it up but: You need to have the aerial on the roof or higher - which you have done. The QUALITY OF SIGNAL should be up high on the meter which your box displays in one of the menus. Siganl strength is not as important as the quality of signal - repoint the antenna correctly. Use "Quad Shield" cable between the antenna and Digital Box. If using a wall socket, get this cable installed to the wall point and to the antenna. Buy Quad shield cable patch cord to connect from the wall socket to the box. Have another if connecting the VCR to the box as well. Optional. Buy a (around $40) filter board that helps stop EM interference. Do you have UHF translators? Tune those in, more resistant to noise. If you suspect the box, take it to a mate's place with a decent antenna and try it there. Check loose plugs at sockets. Attach box power cord to separate power circuit. Quad shield will improve it somewhat, as it just about bullet proofed mine against breakup and being low loss - except aircraft flying over; swinging tree branches touching antenna elements and so on - can't do much about the aircraft, hehe unless you are a good shot! :ph34r:
bruiser333 Posted October 6, 2004 Posted October 6, 2004 Griffs, I'm in a similar position, was about to try some other things but as they didn't work for you I'm not sure what to do now. What high gain VHF antennae did you put on? - was it a band III only? (Alan has mentioned in other posts than Band I & II are more susceptible to interference). Unfortunately there seem to be a lot of theories on how to handle digital TV interference, but all I've tried have had little effect. I hope one day (soon please) they will be cleared up for those with less than perfect reception... Cheers, Bruiser
Griffs Posted October 7, 2004 Author Posted October 7, 2004 Griffs,I'm in a similar position, was about to try some other things but as they didn't work for you I'm not sure what to do now. What high gain VHF antennae did you put on? - was it a band III only? (Alan has mentioned in other posts than Band I & II are more susceptible to interference). Unfortunately there seem to be a lot of theories on how to handle digital TV interference, but all I've tried have had little effect. I hope one day (soon please) they will be cleared up for those with less than perfect reception... Cheers, Bruiser <{POST_SNAPBACK}> Hi Bruiser333 Unfortunately I left the choice of antennae to the Installer and was ignorant of the different Bands available. I will get back to the Installer and try and find out what Band the aerial is. The Installer did not have any specialist equipment to set up the alignment of aerial and just aligned on signal strength and direction of other aerials in the area (proper setting up of alignment to transmitter with digital test set may help with receiving a better 'quality signal'. I will be investigating this option) The raising of the aerial on a high mast provided the best improvement. Break up of picture now effects less of the screen and picture recovers quicker.
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