green tint on TV caused by the center channel

Discussion in 'Speakers' started by david*mt, May 25, 2003.

  1. david*mt

    david*mt Second Unit

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    I purchased the Jensen HTB-805 set from Circuitcity a while ago and have been happy with them until now. Recently I have noticed a light green tint on the top corners of my TV. When I remove the center channel from the TV the tint goes away. So what gives? The center channel is shielded.
     
  2. Jonathan T

    Jonathan T Second Unit

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    Well, it's not shielded enough. Move the center away a little untill the tint goes away OR go in there and stick some more shielding magnets on that sucker.
     
  3. Tekara

    Tekara Supporting Actor

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    a fun and interesting high school physics experiment is blocking radio waves with achicken wire fence. when you take a radio that is currently recieving an electromagnetic frequency (for it's particular frequency we call them radio waves, go figure) you can place it inside a cage made of chicken wire and all of a sudden the radio loses signal.

    well you can apply this same principle to your setup, now consdiering much higher frequencies are being used you will need to use a tighter weave metal cage to block the electromagnetic waves from the speaker to the TV. a fine aluminum mesh has worked well for others that I have heard that had similar problems.

    hope this helps you out.
     
  4. keir

    keir Stunt Coordinator

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    rob, are you sure that works? i thought it required a bucking cancellation magnet to shield the tv from the large permanent magnets present in most speakers.
     
  5. Paul Stiles

    Paul Stiles Agent

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    The radio waves are in the 100s of kilohertz or in the megahertz range. The higher the frequency, the smaller the "chicken wire" mesh needs to be. The R.F. is what is being shielded and along with it the audio frequency modulation of the R.F.

    The permanent magnets in the center channel speaker are not a source of an AC magnetic field (although AC current through the voice coil is) but it is a source of a DC magnetic field. The wire mesh will not work with a DC magnetic field.

    The present shielding of the center channel speaker is not good enough. Perhaps placing the center channel speaker on a non-magnetic sheet of steel plate (mu-metal would be better) that sticks out beyond the edges of the speaker would provide enough additional magnetic shielding so that the unwanted magnetic deflection of the electron beams in the TV will cease. If the steel plate works, it can be painted or otherwise covered to have a better WAF and to not rust. Or you Harley fans can get it chrome plated.

    Paul
     

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