Sony pincusion question

[roobeast]

Hi I have a sony KV-27HSR10 that had a severe pincusion problem. I replaced L501,
Q505 and R571 which were all bad. Now the problem is not severe.
When I turn on the TV there is a very slight pincusion and then after a few
minutes it snaps out of it and the picture is straight. It's like something is
heating up and then kicks in and starts working. Any ideas on which component in
the pincusion amp area could cause this behaviour that appears to be temperature
related. Also if you understand how the pincusion amp circuitry works I'd love
an explanation as I have a schematic but don't quite get it.

Thanks,

Alex.

 

[Shoreline Electronics]

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Text pasted from WinSTIPS 2.0
http://www.ServiceSoftware.com
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SONY KV27HSR10

Pincushion - Picture Is Too Wide - Burnt R571 And Shorted Q505

Brian Lam Bsee

Burnt R571 And Shorted Q505 Almost Always Caused By Shorted L501 7.5mh
1-459-148-13,

If The Plastic Wrapping Is Melted It'S Shorted Or You Can Confirm With An L
Meter. Watch Out For The Pin Out On Q505 ... It Does Not Match The
Silkscreen On The Board. Emitter Should Be Connected To L503.

Service Mode Is Accessed Via A Hole On Back Panel (Where The Rca Jacks Are).
Push Down The Switch (Behind The Hole) While Turning On The Power Will Get
You In To Service Mode. Use Remote, 1, 4 To Change Parameters, 3,6 To Adjust
Data. Mute Then Enter To Save, And Power Off To Exit.

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SONY KV27HSR10

Pincushioning, Both Sides Bow in After About 1 Hour.

Ford's TV & Video Service

Leaky Transistor, Q504 (2SC2785).

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--
==========================
Jeff Stielau
Shoreline Electronics Repair
344 East Main Street
Clinton,CT 06413
860-399-1861
860-664-3535 (fax)
jstielau@snet.net
========================
"If you push something hard enough it will fall over."
Fudd's First Law of Opposition - Sir Sidney Fudd


"roobeast" <post@beast.com> wrote in message
news:ce9e9ed2.0310021228.5a22c5e1@posting.google.com...

Hi I have a sony KV-27HSR10 that had a severe pincusion problem. I
replaced L501,
Q505 and R571 which were all bad. Now the problem is not severe.
When I turn on the TV there is a very slight pincusion and then after a
few
minutes it snaps out of it and the picture is straight. It's like
something is
heating up and then kicks in and starts working. Any ideas on which
component in
the pincusion amp area could cause this behaviour that appears to be
temperature
related. Also if you understand how the pincusion amp circuitry works I'd
love
an explanation as I have a schematic but don't quite get it.

Thanks,

Alex.