Don't Miss


Electronic Repair Questions/Answers And Testimonials Part 1

By on May 27, 2008

Dear Yong,

I really appreciate your kind gesture in trying to make me a good electronic repairer through your daily articles.i would wantyou to explain to me what you mean’t by B+, X ,Z and Y meter used for measuring some components. If possible show me the pictorial diagram as i.m still a baby in electronics and some of this components are not commercially known in the market<i.e as y metre>,

Pls do me a favor by sending the components or tools’ prices or where to get them

D.W

Hi D. W,

Thanks for your interest in my repair articles. For the B+, usually technicians will refer it as B+ voltage which mean Boost voltage. Without this voltage the flyback would not work. As for the meters, yes one should have different meters to test on different electronic components.

Analog meter- for testing diode, transistor, continuity and etc (Could get from your local electronic distributor)
Digital meter-for testing voltage, resistors, current and etc
( Could get from your local electronic distributor)
ESR meter- for testing electrolytic capacitor (Could get it from http://www.electronicrepairguide.com/blue-esr-meter.html)
Digital capacitance meter- for testing all kind of capacitors value
(Could get from your local electronic distributor)
Inductance meter- for testing the inductance value of coils/inductors (Could get from your local electronic distributor)
Flyback tester-for testing coil to locate shorted turns in flyback, smps transformer, b+ coil and horizontal yoke coil in picture tube. (No more in production).

As for the pricing you have to check from them as different electronic shops in different countries have different prices.

Jestine

http://www.TestingElectronicComponents.com

—————————————————————————————————————

Hi B,
Here are your questions and answers:

“The you tube video in your website link is very interesting, how could I record the video and save them to my hard disk?”

Use a digital camera and then upload to your computer, from there use window movie maker to edit the video and after that you can publish and upload to youtube.

“Can the DCA55 Peak Atlas Component analyzer analyze and identify faulty / bad components?”

It depends on what components you are testing. If the components is under the list yes it can test for bad components. I only use it to find out a working components that have a missing part number particularly the transistors, scr and fet. I also use it to test the HFE of the transistor. Other than that i use analog and digital meter to test on electronic components.

“Now I am trying to repair LG 520Si monitor, the only problem is after turning it on for quite a while, sometimes I hear the tic sound from inside, but the tic sound seems to be long enough to occur so I can’t see where it is from even I have opened the cover. The condition of the display is still bright and clear, and I was scared when the tic sound comes.”

The internal capacitor have problem. The value may have out. It should have about 2.7 nf. You can replace a new flyback or refurbish the flyback transformer.

“The other monitor is Korean made LOGIX LGX17H plus comes with the problem of there is no display even the brightness has been set to maximum. When the owner brought it to me, I could still see a blur image from the display and now I can’t see anything, what could the problem be?”

Please check the heater voltage (6.3 Volt dc) as low heater voltage could cause no display or blur display.

Best Regards,
Jestine Yong

———————————————————————————————————

hi jestine

i have to realise that my challege in electronic repair is testing the capacitors mostly non polarised which meter should i use to test a 221 3KV .0047j 1.6KV secondly what is the function of 3.3uf 50v non polarised electrolytic in the flyback circuit next to hot. thirdly i have been coming across some monitors which power off with verticle blue lineand the blue spot.

thanks

Hi Ibu,

You can use digital capacitance meter to test the value and the insulation tester to test for short.

The non polarized ecap so far i’ve seen is in the horizontal size circuit. If the e cap have problem , the display would become big.

The vertical blue line indicates a problem in the horizontal circuit. It could be an open horizontal yoke or a dry joint at that area. The dot could indicates a defective picture tube, faulty G1 circuit or a missing ground in the picture tube. Hope this helps!

Best Regards,

Jestine Yong

==========================================================================

Hi M,

I have purchased your LCD monitor repair book about two weeks ago.

Thanks for your support!

and have a odd problem on a Viewsonic VP201b monitor. My first problem was the monitor had no display, there were power LEDs but it went from green to orange when turned on, like it was going into power saver mode. After inspecting the boards, I found there was a SMD fuse on the inverter board that was blown and stopping the monitor from working fully. After I replaced the fuse with a zero ohm resistor (until can get a replacement), the monitor came back to life but after running for about 5 mins the screen flickers and acts like there is no input and goes into energy saver mode. After I remove the power and let it sit for a while, sometimes it will turn on just fine, but other times it will turn on with the same problem as before, the display flickers, backlight stays on, can’t find a signal, then it goes into energy saver mode. And usually while it is having the problem it won’t respond to any buttons, can’t turn it off, select input or anything, it will just automatically go to an amber light for energy saver mode. I have replaced the crystal for the main scalar IC but not the caps that run the crystal. When I use a oscilloscope on the crystal, one side has a good sinusodial wave at the correct 14.318 mhz but the other has a little different waveform but still at the correct 14.318mhz. I have removed both caps for the crystal and both seem to be good, but I don’t have a cap meter to test the value. Also, with the cap removed there is a slight continuinty between the pads of the cap for the crystal. Is this normal, or is it a possibilty that the board has a short between the board layers? ( It is a 4 layer board). Anyways, I really enjoy working on LCDs and would like to get this one completly fixed. Any suggestions or comments would be appreciated.

In fact i have came across one quite similar case but the model was ACER 17″ LCD. The problem was a slight short circuit (intermittent) between the pins in the scalar IC. If possible you have to use a magnifier glass to closely look at the pins. Sometime a dry joint could also cause intermittent problem in LCD Monitors. Use the rework station to help solder all the IC pins. Set the air power to the lowest and temperature about 450 celcius and apply some soldering paste. Slowly move the hot nozzle across all the pins and hope it could fix the problem. As for the caps, i guess both of it are okay due to that you got the waveform and the correct megahertz reading.

If you have other questions please do email me again. Have a good day!
========================================================================

Likes(0)Dislikes(0)

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Free Report