I got a phone call from a client who wanted his television
checked, I visited the place and was shown the television and when switched on
I noted the picture was only present from the center of the screen to the
bottom and also some retrace lines at the bottom.
Usually whenever you see the screen is not full vertically
means there is some problem with the vertical circuit meaning it is not doing
its work of opening the screen vertically.
Since the owner wanted the TV back urgently he decided to
accompany me to my workshop and once on the bench I opened the set and went
straight to the vertical circuit.
Since there was something on the screen I did not suspect
the vertical I.C and my concentration was on filter capacitor on that
circuit...
Remember the retraces lines? This also lead me to suspect a
failed capacitor on the same circuit and therefore the first thing I did after
opening the set was to scan all the electrolytic capacitors around the vertical
circuit and I was not able to pick any with top swollen and therefore I had to
use the next method of testing capacitors using my ESR meter.
After a few tests I was able to bump on a capacitor C563 (220uF/35V)
which read open according to my ESR meter which has maximum ESR range of 100
Ohms.
At first I could not believe that this capacitor was faulty
since looking at it look very innocent and therefore I had to solder it out of
the circuit and re-test again.
After doing out of the circuit test I also got the same result
(OL) out of range and with this I concluded the capacitor was completely dead.
After picking this capacitor I replaced with another rated
220uF/50V which I had in my capacitor kit which I always buy to minimize going
to the shop every time I need one.
After replacing the capacitor it was not time to do the
testing and after applying the power I was happy to note the screen was now
full.
The whole process took me let than twenty minutes and since
the owner was there I has problem with charges since he thought I have done
very little for the charges I quoted but I explained to him that in repair what
is important is getting to know where the problem is and that is what we charge
for.
I am sure if this set was taken to a tech without ESR meter
it would have ended up in the dust bin which could have been more expensive to
the owner.
Thank you guys.
See you in the next class
Excellent Job. I already purchased mesr-100 from ebay in 65$. It is the best among all. Love to use it.
ReplyDeleteThanks for your feedback. regarding the ESR meter....TELL THEM IN CAPITAL LETTER
DeleteRegards Humphrey
THANKS FOR SHARING
ReplyDeleteWelcome Mr Khan
DeleteRegards Humphrey
You are absolutely right.. the ESR is a vital kit to have..
ReplyDeleteYes! TELL THEM IN CAPITAL LETTERS hahaha
DeleteRegards Humphrey
Thanks Humphrey for this vital information. Iam actually faced with a related problem but for this one the screen displays half way but from the middle upwards. could it still be a capacitor failure?
ReplyDeleteappreciate your experience .. liked it.. just came to your blog and other posts while i am repainting my TV. i have no luck though. My HOT is blowing away. but still i am confident that i will fix it. but nice to read your experiences, keep writing. god bless.
ReplyDeletein my case i have a isolated transformer from the HOT do i believe horizontal driver transistor is fine what do u say