Re: What are the chances of finding a complete board for a 1992 TV ?

From: Jerry G. (jerryg50_at_hotmail.com)
Date: 02/08/05 

Date: Tue, 8 Feb 2005 08:51:07 -0500

Why not give the set out to a service center that is used to working in
these sets?

To have a complete board, you will have to find a scrapper like your set
that is in working condition (very rare these days). The next complication
would be to do all the factory setups in the firmware of the TV uPC to have
it properly match.

You have a cold solder connection, or an intermitting component on the
board, and you haven't found it yet. Soldering a complete board is not the
proper answer.

These boards are using a lot of surface mount componets. They are difficult
to work in, unless properly trained, and have the proper soldering equipment
to change any that are defective. It is possible to have a component that
the solder connection under it has become a cold connection. It is also
possible to have a trace on either side of the board that is intermittant.

You should have the board jigged up so that you can gain proper access to
it. Have the service manual open in front of you, and troubleshoot the board
while the fault is occuring. Since the picture is very bright, I would be
looking in anywhere that can effect the screen bias, high voltage
regulation, or CRT drives.

When this board was available from Sony, it cost was very expensive. I have
never seen anyone have to replace a whole board to fix a cold solder
connection, or an intermittant component in the model of TV you have. 

-- 
Jerry G.
=====
"da_test" <davexnet02NO@SPAMyahoo.com> wrote in message
news:v9mg0116hfbvl2uccv140qaha85jmjbe13@4ax.com...
Hello,
despite my best efforts, I still seem to have an intermittent
fault of some kind related to the Jungle y/c board.
It sits vertically in the chassis.  All I need to do is give it
the slightest tap on top of this board
and the normal picture is restored.
I've attempted to solder the board, but except for the IC chip,
and the plug in connectors, almost all the components on this
board are microscopic.  (What are those tiny rectangular
looking things?)
The TV is a 1992 Sony kv27-xbr35.
I'm currently using it with the back off.  When I switch it
on in the morning, picure is bright blue with retrace lines.
A tiny tap on the board restores the picture for the rest of the day.
It's really bizarre.
If the board was available I swap them out in a heartbeat.
As far as I know getting this board is probably next to impossible.
Appreciate any advice.
Dave

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