Tuesday, October 25, 2011

Customer support-via email between me and a customer from Philippines

Randy: Our television Toshiba 21 inches, picture is stretched on top of the screen with thin white lines.

Humphrey: I can’t get your point maybe you can send me the picture of the same.

Randy: These are the pictures I've taken. As you can see on the first picture, the logo on the upper right corner is really a square one but is stretched upward. Also the head of the person stretched upward. The color black at the bottom appears after i replaced the ecaps. According to my mother, the black color will go down when the unit heats up.

The second picture happens during commercial of the tv program. What do you think the problem sir and what should i do to fix it? Thanks

 Humphrey: This symptoms points to the vertical circuit, read chapter 14 again slowly and you will get very good clues on where to check.

But capacitors, dry joints are highly suspected here. Please be sure to change all the capacitors related to the vertical ic used in this TV if you don’t have esr meter.

Be sure to check also the main filter capacitor for the vertical circuit…what is the  ic used for this TV? Google it and you will be able to see the main capacitors around this ic.

I don’t expect much of a problem here randy…

Randy: It’s been a long time that I send you my problem on our Toshiba tv. I work on this only during weekends because I have work during weekdays. I reviewed your eBook about the vertical circuit and I had replaced already the ecaps near the vertical ic but still the problem is still there. But this time the display has an intermittent raster. I have traced the circuit from the vertical ic going to the jungle ic and I found that there are ecaps no. c301 and c305 which is still part of the vertical circuit. I replaced it directly because I don't have an esr meter and power on the unit and wow the display is now normal. The lines on top of the screen are gone. 

Humphrey: WOW!!!!! Congratulations Mr Randy.

Very glad to hear that success report...even me I do repair during evenings/weekends because I have another full time job as an IT/Account assistant.

Randy: Important information that I learned from this TV is that it operates in low G2 voltage. The G2 voltage is only 88 volts DC.

Humphrey: Very good observation Randy…I have also come across TVs (especially the old ones) having G2 voltage around that range and works okay...When you try to make it go up the set will shut down or behave abnormal….

Sir thank you very much with your guidance.


Most welcome Mr. Randy, stay safe


Author CRT Television repair course

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