Dry joints in Horizontal & Vertical circuit in CRT -TV solved
This TV came to me from one of my workmate, complaining that it has horizontal white lines on the screen. But he can still see the picture behind those white lines, and the picture is also faded. These were the information’s on the sticker from the manufacturer:
I powered the set and wanted to see what is the actual interpretation of the customer, when I turned on this set this was the screen that I was able to see: (as you can see the white lines)
After this I decided to open the set and do the troubleshooting of this problem. But before I open this TV I tried to make out what might be the problem so that I can work according to my interpretations to save time, and wasting time unnecessarily on circuits that are not in relevant to this problem, these were the following things I came out to start my trouble shooting:
· Dry joints in vertical and horizontal circuits,
· Bad capacitors in vertical and horizontal circuits
When I opened the set, and scanned with my naked eyes through the vertical and horizontal circuits, I never found any of the capacitors bulged/swollen.
But here I tried to change the four capacitors in vertical circuit, as marked in the picture above, these capacitors lay on the pins of the vertical IC. Actually this was not the problem but was just doing a trial that can improve the screen status, because I don’t have any ESR meter to know the ESR of the capacitors so I just directly substituted these capacitors. (but this was not the problem).
I again turned the board the other side and tried to look for dry joints:
These were the 7 pins of the vertical IC, was resoldered.
But still there was no difference on the screen noted. Moving on I resoldered the horizontal circuit up till the fly back transformer where the actual dry joints were found, and the problem was solved.
MISSION ACCOMPLISHED THE CUSTOMER WAS INFORMED THE HIS JOB IS DONE AND HE CAME WITH A BRILLIANT SMILE ON HIS FACE TO PICK HIS TV………..
Have nice repair journey friends.
This article was prepared for you by Atish Chand From Fiji Islands.
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yogesh panchal
July 28, 2014 at 6:34 pm
Atish, good job keep it up and thanks for sharing.
Robert
July 28, 2014 at 7:04 pm
Nice job Atish! Thanks for the article. You need to get the Blue ESR meter from Mr. Yong. I'm going to get one probably next week. I already have an ESR meter, but it won't check batteries. You can check the ESR in batteries also with the Blue ESR meter. But I believe that we can never have too much test equipment!
Robert Calk
August 3, 2014 at 9:57 pm
Mr. Yong's store was out of the Blue ESR meters Friday, so I ordered one from Anatek.com. I also ordered a CCFL backlight tester. I can't wait till my new tools get here.
zed
July 28, 2014 at 8:13 pm
nice job atish.
Austin onweaba
July 29, 2014 at 6:13 am
Nice work,but how can open circuit in horizontal section cause this type of fault? Explain it more to me how it can cause blanking fault.
Corriette
July 29, 2014 at 7:19 am
yes sir good job.
beh
July 29, 2014 at 10:13 am
HI ATISH
all crt s older than five years services are suspect to dry joints
all over the world. where this crt was giving the service also is a point. closer to seaside makes this problem more critical .
keep up&thanks
beh
Robert
July 31, 2014 at 3:28 pm
It seems that even brand new devices are suspect now with the non-leaded solder. Usually the first thing I do is remove the transformers and after checking components, solder it back with good leaded solder.
rommel mananguite
August 14, 2017 at 5:56 am
my problem is vertical.what is sulotion all tv circuit is checked.