thank’s  you for your reply sir,

sir I remove the back light jack’s one after one, and I start the lcd tv for each time, In eack time I get the same problem that back light goes with in seconds, there is no dry’s in  HV transformer, the mosfet’s are ok, now what can I do, can I chage the inverter board, in that case can we replace the same board or any tv’s inverter board, It has 6 out put sockets for the back light

thank you sir,

Hi Siva,

No you can’t remove the backlight jack as this will cause shutdown due to the feedback circuit. A weak backlight will cause the display to shutdown. You need a good one to do the comparison work. or you can get a backlight tester to do the job.



hi mr yong I’m hadi from is iran i hav a sumsong lcd monitor (920nw) it have a problemwhen i trun on it ., it work for a secend and trun off a back litgh , i chenge a ic mosfet , ic inverter and chok but for secend worked and trun off a backlith.. how i can repair it ..

when i cheang the board power &inverter  the panel worked without problem.

Hi Oranus,

Make sure the supply voltages from the smps are good and the inverter ic is getting supply even though it has shutdown. Compare the reading of the high voltage transformer and surrounding components using ohms range. Any different in the ohm reading is the clue for you to locate the fault.



Hi Eugene,

a. My analog multimeter one day i am using,  the needle no longer pointing at zero. It stays at 20K range. What seems the problem? defective resistors?

If it can’t be adjusted back to zero from the front panel then the needle assembly already have problem and it can’t be repaired.


b.  My desktop computer casing has an electric shock, I checked it nothing bare wire touching the case.  Power supply going bad?

Try check the earth/grounding cable. Most of the time user use power extension cord/plug that had caused loose connection in the grounding.


thanks for your feedback, Sir which of the following Ic is the problem for the backlight off in seconds and the tv in on condition, sound ok, remote and the chanels are ok,

LM 339A



can you supply the parts for lcd tv.

please give me reply sir,

Hi Siva,

Sorry i do not sell parts.The OZ964SN is the inverter ic. Inverter IC rarely have problem , usually is the corresponding fault.



What is replacement or equivalent to FET K2544 ?

HI Aida,

Then you can use K2645 as replacement. Make sure all components are good before turning on the power.



Now i must tell you i learn a lot from your ebooks and newsletters keep on sending them for me

i fix alot of monitors throu your ebooks,

i must say thanks to you and have a bless day.

johnie jones


Hello Jestine,

Thanks in advance for your great news letters and technical helps. I’m trying to repair a IBM E74(Model no:6332-4CE/A) 17″ colour CRT monitor. The monitor is completely dead,no power. When I opened the monitor I found the switching FET( STP9NK70Z) and HOT (C5929) were short circuited. Fuse and rectifier diodes were ok. I am unable to find STP9NK70Z in my local market, can I replace it by STP9NK90Z?

Awaiting your reply,

With Regards


HI Apsin,

Yes you can use that replacement number.




Hello Jestine,

I hava a Intex crt monitor 15″ , the problem is width excess. The width is adjustable about 1.5″ but can’t be reduced less from screen area. When i decrease the resolution then it can be extra reduced from screen size. I have changed TIP 122 (width control) but no result. The width control is working and there is no preset inside to adjust further. I have not checked other components because width control is working and also horizontal shifting working. Hence, i need your valuable suggestion in this case.


Gopal Sharma

Hi Gopal,

Try check the capacitance value of the holddown/safety capacitor.If the value is out the display width can be affected.




k thank you sir thanks a lot sir . . . .can i put ordinary glass fuse
instead of T3 fuse?

Hi Raga,

You need to put back the slow blow fuse. Normal glass fuse (fast blow fuse) will not stand and may blow again.


Dear Jestine

can you help me with this. I have a doubt about the reading. I worked it
out to be a 2R5%

The colors are:


Did i mixed the colors? Hope to hear from you

Hi Koniel,

Ignore the white and you will get 0.2 ohm. +/- 5%



K sir when resister burnt immediately what reason behind this kindly
please tell me i am so confused thank u so much
with regards

Hi Raga,

Resistor burnt in power supply can be due to shorted components in the corresponding circuit or from the main surge/lightning strike.



i want to start a repairing centre please suggest me how could be it possible.

HI Mansoor,

You must know how to repair and have quite a number of customer base in  order to start a repair center. You can start from your home first and if the customer base is big enough you can rent a bigger space. No matter what please always check on your cash flow.



hy justine,

i have caught a problem with my television.It is not showing display, only shows vertical lines what should i can do now.

Hi Asim,

Vertical line you need to check on horizontal area and one horizontal line you need to check on vertical area. Since your complaint was vertical line then make sure the horizontal yoke coil is properly connected and no bad components surrounding this area.



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