Hi guys
i have a problem with a panasonic 20 inch colour tv board no.ADP 269
the problem is i have a thin straight line across the screen when it is powered up witch indicates to me that i have a vertical problem.
I check all the components in that circuit which tested to be ok,
I change the vertical deflection ic no.la7835 but to no avail. Could someone point me to the next possible step.
Thanks in advance

 

I'd start by getting a Howard W. Sam's Photofact schematic for it, if you don't have one already. They will save you a lot of head-scratching. They are not free, but your time is worth something, too.

Website: http://www.samswebsite.com/photofacts.html

 

Open circuit in the vertical deflection coil.

 

First and for most, never leave the set open with a bright line in the middle even when trouble shooting, This will damage the phosphor, and you will end up a visible vertical line . Always limit the brightness or screen so that the line is barely visible to the eye and work.
Second get a schematic for it, if you cannot find then post back, I'll see what I can do.
Third is that you should know your way around a TV and should have proper soldering practice when repairing a TV.

 

Does it have deflection yoke on the neck of the.picture tube.
If you have a white line your high voltage is o.k. don't
mess with it,you will end up with more problems.

 

I found out recently that our local library has the Photofact docs. Shelves full of them going back to the late 40's. I grabbed a copy of the schematic of my 1945 Emerson battery powered tube radio. Just paid a few coins to use the copier. Check around, maybe your library can get them for you.

 

First and for most, never leave the set open with a bright line in the middle even when trouble shooting, This will damage the phosphor, and you will end up a visible vertical line . Always limit the brightness or screen so that the line is barely visible to the eye and work.
Second get a schematic for it, if you cannot find then post back, I'll see what I can do.
Third is that you should know your way around a TV and should have proper soldering practice when repairing a TV.

Thanks for the info.
I tried searching for the schematic but found none. Yes i know a bit about tv`s and i have very good soldering skills. I attend classes of television repair crt that is, but i want to impress my instructor by figuring this one out by myself and with the help of you guys.

 

Does it have deflection yoke on the neck of the.picture tube.
If you have a white line your high voltage is o.k. don't
mess with it,you will end up with more problems.

Vertical deflection yolk tested ok

 

can you take pictures plus I need the TV model no.

 

can you take pictures plus I need the TV model no.

Model no.--- ct-20R13U
will get pics later

 

http://www.owner-manuals.com/index....eyword=ct-20R13U+service+manual&forward=plist

I have searched for the service manual and it seems that one have to buy it, above is a link that I found.

Now when it comes to repairing CRT's, one should have the service manual so that one can speed up the process.
And if you get stuck I should have something to refer so that I can guide you to repair the TV.
I am confident enuf that I can fix the TV, but in this situation you are the puppet .
In order to pull the strings we need the diagram.
So if you want it to be repaired then get the service manual, If I had it I would post it, Panasonic manuals are very rare indeed

PS. I think I sound like loosewire.

 

Hello,

Perhaps this page wiil give some hints:
http://www.repairfaq.org/samnew/tvfaq.htm

Greetings,
Bertus

 

Thanks to all you guys for the inputs, it really helped.
Problem solved. After all parts tested good, there was a cold solder at the power ic

 

Sometimes it's the simple things that bite you.

Glad you figured it out and got it fixed.

 

Sometimes it's the simple things that bite you.

Glad you figured it out and got it fixed.

Dido