stringpikcin |
Posted: Sun May 18, 2008 11:36 am Post subject: jitter, jitter not, jitter, Hitachi 61SBX59B |
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Hey and good day.. I can't think of a better way to describe the problem than the title. If you close the front door the picture will jitter and settle...........maybe, then sometimes it will jitter up and down, the top corners will jiggle in.. But never does it go black. It is as though the picture looses configuration and then snaps back. Tap on the side of the TV and most the time the jittery picture will react to the tap. If left alone usually the picture will settle in to hours of operation without any jitter. Sometimes jitter every now and then. When it is jittering if you lightly tap on the bottom it is affected generally double as much as tapping the upper side.
When a friend plugged in his xbox to the front input, the sound from guitar hero, is that xbox? Whatever,, man the picture was affected so much by the game noise that we had to patch the sound directly to the receiver and not use the tv speakers. Anyway it acts mainly as though it is a loose connection. When the TV is cold and turned on fresh it takes a while before it stops jittering and becomes stable.
So a thought occurred to me from a lesson about a 220 dryer circuit receptacle that caused the cord from the dryer to literally melt. I am wondering if it is possible something like this is going on with a connection and/or a component on a specific board. If it is I figure I could pull it out and solder it or replace the component fairly easily. But I know nothing about that part, the part that tells what it is that I am fixing or replacing. If I can find the thing I can get it cut out and a new one soldered in if it needs to be done.. But I need direction.. lol
Anyway, the 220 receptacle itself had melted also, and actually partially burnt to the point of brittle on one side of it and cracked apart. Fortunately the wires almost got hot enough to have to be cut back 5 or 6 inches, luckily didn't have to, they were still safely useable.
My theory of what happened is that the receptacle from 30 years of being used heated up, cooled down, heated up, cooled down and eventually loosened the connection. The wire basically would compress some eventually. When I checked the surviving connection on the plug, If I would have just installed that wire, the set screw could have easily been turned at least a half a turn or more to be snug. I could feel the wire shift back and forth slightly when moving the plug out of the box and pushing the wires around so that one could get to the set screws. Those wires are stiff, so if they are not tight, when you shove the plug in the box the wires bend and can actually shift under the set screw. That’s what I felt upon inspection, As I pulled and stretched the wires out of the box to repair it I could feel the wire in the connector stay in place and the plug rotated on it.
So my theory is the wire had a lousy connection and backed up the juice and melted down the surroundings.. In my TV’s case I am thinking a solder point is basically doing the same thing. But being it is such low voltage I merely affects the circuit by not functioning. Any voltage that is not getting through could do some damage if the path ever becomes severed completely. Would be nice to find it before than eh? So is there a place on a board that is known to cause this problem.Sure appreciate your time and help. Thank you.. Stringpickin |
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