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Sony trinitron kv-28 fd1e

 
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yoharryo
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PostPosted: Thu May 19, 2005 8:55 am    Post subject: Sony trinitron kv-28 fd1e Reply with quote

I have a Sony trinitron kv-28 fd1e. It is a wide-screen.
yesterday, two black 'curves' around the edge of the screen appeared. this also distorst the picture in the center. It doesn't matter what is plugged into it, vcr, dvd it does it with everything.
It is definately not anything to do with zoom, or aspect ratio, as I ahve tried changing every one.



thank you

Harry
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walter58



Joined: 11 Apr 2005
Posts: 20
Location: Antwerp,Belgium

PostPosted: Sat May 21, 2005 11:59 am    Post subject: Sony Trinitron tv Reply with quote

Hello,

This is quite shure the "East-West" correction stage which is not working anymore, this can be caused by the supply for this stage,which could be absent, or the integrated circuit (sometimes also just an output transistor) which is defective !
Since I have no notice of the schematic diagram, I can't help you more than this, but I can tell you that the east west correction circuit is in the neighbourhood of the horizontal output stage, near to the LOPTR .

The East west correction is a parabolic tension, which is implemented in the horizontal deflection voltage, so if there is no east west correction added to the horizontal output stage which drives the horizontal deflection coils, the screen will get smaller and you'll see pin cushion distortion as in your photo...

Whith some repair knowledge and a schematic diagram, you should be able to spot the problem and repair it yourself; look in any case for a burnt resistor in the horizontal output stage, because some power is driven in the east west correction, and try to spot the IC and replace it! Cool
Succes !
Walter Cool
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walter58



Joined: 11 Apr 2005
Posts: 20
Location: Antwerp,Belgium

PostPosted: Sat May 21, 2005 12:06 pm    Post subject: Sony Reply with quote

hello again,

just remembering something : I once had the problem coming from the booster capacitor, which is in the horizontal output stage put across the horizontal output transistor and cures the picture width !
this capacitor is a bipolar type, mostly 8 to 12 nFarad/2kVolts.
mainly blue coloured.
You understand that I (sitting here in Belgium) can only give you a tip and not a solution, and that far away nothing is sure known...

Wink

Walter
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never give up when you are looking for something,unless you're forced to !
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newby
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PostPosted: Thu May 24, 2007 9:59 pm    Post subject: Reply with quote

repaired one today, replaced fuse PS1502 (yellow labeled "1000") with a stronger fuse (1500), thats it!
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