HELP! Think new HDTV got zapped by lightning!

Discussion in 'Displays' started by Chris Shooter, Jul 26, 2004.

  1. Chris Shooter

    Chris Shooter Auditioning

    Joined:
    Jul 8, 2004
    Messages:
    14
    Likes Received:
    0
    Trophy Points:
    0
    I have a Samsung TXN3075WHF 30" Widescreen HDTV and it's not even a month old. Tonight when I came home from work there was a pretty bad lightning storm going on. I was changing my clothes when a bolt of lightning hit something really close to the house. The power didn't go out or anything and it seemed like all electronics were still functioning. I have my HT equipment plugged into a surge protector strip, plugged into an APC Surge/Backup. Nothing was tripped. After the storm went away, I turned on the equipment and now notice in the upper right corner and lower left corner radiating outwards a couple inches of green or purple (changes colors depending on the video image). The rest of the picture looks fine. What the heck happened? HEEEEELLLLPPP!
     
  2. Allan Jayne

    Allan Jayne Cinematographer

    Joined:
    Nov 1, 1998
    Messages:
    2,404
    Likes Received:
    0
    Trophy Points:
    0
    The shadow mask in the picture tube picked up some unwanted magnetism.

    See if the problem goes away after a week of normal TV viewing. Direct view CRT TV sets have built in degaussers that generally are activated each time the TV is turned on after having been off for about an hour. If ten times fails to clear up the problem, you should have a serviceman come in with a portable degaussing coil. Worse comes to worst, the shadow mask got warped as well and the tube needs to be replaced.

    It is possible that lightning produced a magnetic field strong enough to magnetize the shadow mask.

    Also a speaker (or any strong magnet) sitting nearby, or even a speaker carried past the TV closely, can cause this problem.

    Video hints:
    http://members.aol.com/ajaynejr/video.htm
     
  3. Chris Shooter

    Chris Shooter Auditioning

    Joined:
    Jul 8, 2004
    Messages:
    14
    Likes Received:
    0
    Trophy Points:
    0


    Yes, that's what it would seem like. As if someone put a large magnet in the corners of the screen. Like I said, the lightning hit very close - possibly right outside the sliding glass door next to the family room. I turned the TV back on this morning before work and the splotches are gone. Something else I now notice... When a 4:3 image is displayed and it has the black bars on the right and left, well on the left side of the image it is slightly concave - or rather it bends inwards. The right side is fine. Does this make sense? Is there a setting to adjust that?
     
  4. Allan Jayne

    Allan Jayne Cinematographer

    Joined:
    Nov 1, 1998
    Messages:
    2,404
    Likes Received:
    0
    Trophy Points:
    0
    TV sets have various "geometry" adjustments to correct concavities, curved lines, grid test patterns that look non-uniform,etc. SOmetimes you have to go into a service menu to do this and sometimes going into the service menu yourself voids the warranty. Check your instruction manual. Since the set is quite new, you should be able to get this adjusted without having to pay anything.

    To this day, getting a geometrically perfect picture on a CRT is difficult to do. The really upscale sets use microprocessor control to achieve this with sixty to 120 zones on the screen that need to be individually calibrated. If the left edge is only slightly concave, a serviceman may say it is within normal tolerances.

    Just my .02 worth but if you plan to return the set, don't make any mention of lightning.
     
  5. Vader

    Vader Supporting Actor

    Joined:
    Mar 19, 1999
    Messages:
    810
    Likes Received:
    24
    Trophy Points:
    0
    Real Name:
    Derek
    Chris,

    You say that you have the surge strip plugged into the UPS, which is plugged into the wall? With this configuration, you are risking a short should the UPS go to battery power. The reason is that if the UPS is of the common computer variety, it will put out a sawtooth waveform when on battery power. The surge strip can interpret this as a surge, and shunt to ground. This can result in the UPS being shorted out. When I used a UPS on my HT, the surge strip was plugged into the wall, and the UPS into that. I checked with both Monster and Tripplite (in my case), and they said that configuration was OK, just not the other way around. I stopped using the UPS because of the sawtooth wave issue, but if you must use one look for one that outputs a pure sine wave when on battery power, not one designed for a computer (which does not care if it is a sawtooth wave). Hope this helps!

    Peace... Derek
     
  6. Chris Shooter

    Chris Shooter Auditioning

    Joined:
    Jul 8, 2004
    Messages:
    14
    Likes Received:
    0
    Trophy Points:
    0
    In the product specs it says: "On-Battery Waveshape: Stepped Sine-wave". Is that good? Also, I obviously have the powerstrip plugged into it for the number of available outlets. How am I supposed to increase the number of outlets if I can't have a strip plugged into the UPS?
     
  7. Vader

    Vader Supporting Actor

    Joined:
    Mar 19, 1999
    Messages:
    810
    Likes Received:
    24
    Trophy Points:
    0
    Real Name:
    Derek
    Chris (Apologies for messing up your name... I was half-awake),

    There are two issues here. First, the "stepped sine wave" is not the same as a smooth sine wave. A computer does not care, but HT systems are much more sensitive in both audio and video. At best, noise can be introduced into your presentation. Depending on the audio/video resolution you are listening/watching on, you may or may not notice any AV noise. You need to determine that for your set-up. As a fist step, put on a DVD, pause it, and use the test function of the UPS to get it on battery power. Turn the volume of your amp up to the point where you hear either white noise or static (DO NOT take the DVD off of pause here...:-D). Make a note of the volume position. Turn it back down, shut everything off, and remove the UPS from the system (everything is plugged into the surge strip). Power everything back up, bring up the DVD again, pause it, and turn up the amp volume to the same place it was before. If you hear the same level of static or white noise, the UPS added nothing. If on the other hand, the static/white noise is gone, it was introduced by the UPS, and I would consider leaving it off. I did the same test at the advice of others on this forum, and concluded that the noise it introduced was not worth it.

    Second, you need to consider when plugging everything into the strip or UPS that there is a max AMP limit that the unit is rated for. Usually, it is 15A (that is a LOT of current), but check your docs. If you have your HT all plugged into the strip/UPS, consider the following (taken from my HT):

    RPTV: 280W RMS = 396W VA = 3.3A
    Surround Amp = 270W RMS = 382W VA = 3.2A
    DVD Player = 30W RMS = 42W VA = 0.4A
    Subwoofer = 300W RMS = 424W VA = 3.5A

    That gives a total of 10.4A, well below the 15A limit. But that is also only 4 plugs. If you are using a 6 plug strip combined with a 4 plug UPS, that leaves 5 plugs open. You need to consider how much draw the additional stuff will pull, and make sure that it is below 4.6A (assuming you would be using them at the same time as your HT - an additional sub, pre-amp, etc). Note that the numbers are NOT additive (ie. 15A for the strip and 15A for the UPS... all that matters is how much is being pulled through the device plugged into the wall).

    In any case, you should have the strip plugged into the wall and the UPS plugged into that. Either way, you have the same number of receptacles available. You have to decide which are backed up and which are not. If you have not been bitten by a power outage whereas the strip clamped down shorting the UPS, you have dodged a bullet, my friend...:)

    Peace... Derek
     

Share This Page