Sanyo DP40142 No backlight

[Herbssat]

Re: Sanyo DP40142 No backlight

Thanks Kasfamily. Sorry for the quality. They were taken with a cell phone. I will get a picture of the bad component posted sometime today.

[Herbssat]

Re: Sanyo DP40142 No backlight

Here is a pic of this bad component. It is the best quality i can get at the moment. I am sure you are right about that da transistor. There are 2 of those and this w1 is connected back to back with the one you identified.

[kasfamily]

Re: Sanyo DP40142 No backlight

Hi Herbssat! Necessary though, would be like this

[Herbssat]

Re: Sanyo DP40142 No backlight

Thanks. What did you take that picture with? Will see if i can find a better camera.

[Herbssat]

Re: Sanyo DP40142 No backlight

These pics may be slightly better. I still cannot get enough zoom to help you identify what q005 is. I am working on it.

[Herbssat]

Re: Sanyo DP40142 No backlight

A little better picture of the bad component.

[kasfamily]

Re: Sanyo DP40142 No backlight

Q005 marking W1 maybe STA3250F

[Herbssat]

Re: Sanyo DP40142 No backlight

Thanks Kasfamily. I have got a little better picture now. Check this one out.

[kasfamily]

Re: Sanyo DP40142 No backlight

Well and you ask why need good photo transistor, here in the last photo you can see everything and search would have taken much less time.

[Herbssat]

Re: Sanyo DP40142 No backlight

Thanks for hanging in there with me Kasfamily. I had to download a third party app in conjunction with my camera phone to get a good shot.Now i have to match the ratings of this transistor with another.I will probably have to get a generic from another company. Once i find it and put it back on the board i will post my results.

[kasfamily]

Re: Sanyo DP40142 No backlight

Ok.Well, what's wrong with Q005, shorted transitions?

[Herbssat]

Re: Sanyo DP40142 No backlight

Hey Kasfamily. I had a lot of runs to make today.Here is detailed testing of this transistor.

Using positive lead
Base to emitter-OL
Base to collector-0.001
Emitter to base-0.566
Collector to base-0.001
Collector to emitter-OL
-0.563(swapped leads)

[Herbssat]

Re: Sanyo DP40142 No backlight

Here is an update on this set. Replaced the pnp transistor (Q005) and the backlights turned on for about 30 seconds and shut down again. Was able to get them back on but only sporadically. The 24 v is there when they shut down and i am simulating the bl_on signal with a 3.2v battery pack. When it was working the vout was about 140.75 on the driver board.

[Herbssat]

Re: Sanyo DP40142 No backlight

Anyone know where i can get a SUS400 A73 4led type a backlight strip from? Haven't found one anywhere. Your help is appreciated.

[kasfamily]

Re: Sanyo DP40142 No backlight

SUS400 http://www.kittv.ru/product_details.php?item_id=1280

[Herbssat]

Re: Sanyo DP40142 No backlight

Thanks again Kasfamily. I need to hurry and get these on order. I also ordered a tr10e1 ic from china. Getting a lot of weird erratic voltages coming from this chip. I could not bridge the backlight strip well enough evidently as the driver ic may be sensing a problem. According to the handmade jpg you sent i have no voltage out at pin 11 going to the base of q008 and no 7.7 volts going to q004. Do you guys celebrate christmas in russia? I would love to send you something in a monetary form for your help.

[kasfamily]

Re: Sanyo DP40142 No backlight

Hi buddy, I now can not actively help, because left for vacation on the Red Sea in Egypt. Thank you for your appreciation of my modest help, but nothing else. Of course Russia celebrates Christmas, but only on 7 January. Still wanted to ask - where from are you ?

[Herbssat]

Re: Sanyo DP40142 No backlight

Hi Kasfamily. Enjoy your vacation. I am from the US. I am currently trying to order the strip. I hope they ship internationally. Appreciate all your help.

[Herbssat]

Re: Sanyo DP40142 No backlight

Are there any more suggestions for obtaining this strip or a creative way to fix this. I would like to put the original strip back in if possible. The russian company that kasfamily referred me to does not ship to the us.

[Herbssat]

Re: Sanyo DP40142 No backlight

Here is an update on this set. Replaced R053 whose value had increased to 1kohm. It was supposed to be 85ohms. Capacitor c032 was also bad next to it. Since i could not find the backlight strip that i needed anywhere i resorted to jumping the strip with a piece of 24gauge solid bus wire. It was also recommended in a russian forum that the contacts on the backlight strip be soldered to each other because of poor connections. I havent done that yet. I appreciate all the info and help that i got from kasfamily. This was a dog. No panel parts to be located except in russia. This set was designed to fail. Now i must clean the panel parts and put the tv back together. I ran it for about 9 hours straight. A picture of the working repair is attached.