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Tony Miklos[_2_]

On 1/17/2011 8:17 AM, wrote:
On Sun, 16 Jan 2011 23:25:37 -0500, Tony Miklos
wrote:

On 1/16/2011 9:18 PM, PE wrote:
Hi all: My 15-yr old Toshiba 27" crt television has recently developed a
problem which is that approx 15 minutes after being turned on, the picture
bows inward on the left and right sides. Then, after a few more minutes,
the picture resolves and returns to normal and remains perfect for the
remaining time the tv is on. If the symptom described above means the crt
is wearing out, so be it, the set will soon be history. However, I'm
wondering whether some other, replaceable part, might be going bad and
causing the temporarily distorted picture.

Would appreciate any suggestions re. probable cause(s) of symptom described
above. Am basically novice, but handy and with soldering skills, and have
done a few simple tv repairs in the past. Thanks for your replies!

I'll bet it is a bad capacitor, fixed hundreds of video game monitors
with similar symptoms. Most of the time we don't even test the caps,
look for parts of the circuit board that look like they run hot, then
replace all caps in that area. Also replace all caps rated for 100
volts or higher, they go bad much more often. Also if you know your way
around a monitor, be sure to change the caps in the vertical and
horizontal circuitry. For newbies in the video game monitor repairs,
lot's of people put together a list of all the common caps that fail on
that particular model and sell you a bag of caps and a picture showing
what goes where. The "cap kits" will fix several problems at once,
including problems you didn't notice yet but are about to go.

Actually my TV is doing the same as yours but it stays that way. When
it quits I'll probably take a look inside, but chances are I'll toss it
and get a new one instead of fixing mine. TV's have a lot more
components than cheap video game monitors and aren't as easy to fix (not
for me anyway).

OH, no way is that a sign of a bad CRT, and no way is the yoke itself
bad, just the circuitry that powers the yoke.
To be accurate, the problem is low voltage in the horizontal
deflection circuit. MOST likely capacitor related, but there are
numerous other components that can cause it - some of which are more
temperature sensitive than capacitors - and bad solder joints do fit
the category.

In my findings 99.9% of the time it was a bad cap, and while at it I
changed other caps that had a history of failing. I've also found caps,
especially ones that suffer from ESR are very temperature sensitive.