Red/Green/Blue stripes on screen.


Greetings group.
Philips ctv model 25GX1886/75R.
Tv fell off its perch face first onto the floor (around 40cm).
Power switch assembly had been dislodged.
After remounting the switch, ctv still would not turn on.
With the help of a magnifying glass, I found
cracks through around 18 tracks which were repaired.
CTV now turned on, but the picture could barely be seen through
many vertical red/green/blue stripes right across the screen.
Sound is fine.
Shorting each gun to ground did not produce only a red, green or blue
screen.
It only changed the strips slightly.
I suspect the shadow mask has moved inside the picture tube.
What do you think?
Thanking you,
Russell Griffiths.
Reply to
rg26ce1991
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insurance job
: Greetings group. : Philips ctv model 25GX1886/75R. : Tv fell off its perch face first onto the floor (around 40cm). : : Power switch assembly had been dislodged. : After remounting the switch, ctv still would not turn on. : : With the help of a magnifying glass, I found : cracks through around 18 tracks which were repaired. : : CTV now turned on, but the picture could barely be seen through : many vertical red/green/blue stripes right across the screen. : Sound is fine. : : Shorting each gun to ground did not produce only a red, green or blue : screen. : It only changed the strips slightly. : : I suspect the shadow mask has moved inside the picture tube. : : What do you think? : : : Thanking you, : Russell Griffiths. :
Reply to
Ed ()
never let a TV fall off.
Greetings group. Philips ctv model 25GX1886/75R. Tv fell off its perch face first onto the floor (around 40cm).
Power switch assembly had been dislodged. After remounting the switch, ctv still would not turn on.
With the help of a magnifying glass, I found cracks through around 18 tracks which were repaired.
CTV now turned on, but the picture could barely be seen through many vertical red/green/blue stripes right across the screen. Sound is fine.
Shorting each gun to ground did not produce only a red, green or blue screen. It only changed the strips slightly.
I suspect the shadow mask has moved inside the picture tube.
What do you think?
Thanking you, Russell Griffiths.
Reply to
Eric
It's indeed possible, and sounds likely to me from the symptoms - but on the other hand I have seen much more violent treatment than this, worst being a 25" CRT (its enclosure falling from a moving vehicle at about 80km/h onto the road) - and convergence/purity was 100% afterwards, so I would consider a 40 cm fall to be relatively minor by comparison, but you never know with these things. Then again if it was onto a hard concrete floor - its a different matter too :)
I presume you have tried the degaussing wand, adjusting the purity rings (if it has any) on the tube neck, making sure the yoke is still aligned on the neck properly, and such ?.
Checking for cracks, damaged or dislodged components on other boards, damaged or dry solder joints caused by mechanical stresses of the fall on heavy components etc might be an interesting exercise too come to think of it.
Reply to
KLR
Falling off the back of a moving vehicle onto a road at 80km/h versus 40cm to a concrete floor. Hmmmm.... if I was the TV I think I'd opt for the later option. :) BTW what brand of TV survived the 80km/h road ordeal?
Reply to
Alan Rutlidge
It was in an arcade game machine, plywood case with the tube directly mounted on a plywood frame inside.
The cabinet broke apart at the joins but didnt completely disassemble into separate pieces, (possibly due to internal wiring harnesses and large metal angles bolted through at some of the joins) and managed to hold together enough to not let the tube fly out. By some miracle - no part of it managed to hit the fragile CRT neck.
I do have a photo of the thing after the accident lying around somewhere, showing what a close call it was !
The monitor type was a "glendale electronics" brand. I have also seen this identical tube/yoke type used in some of the european made "fujitsu" 26" sets from the early 1990's or thereabouts. TOtally different chassis though :)
Reply to
KLR

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