Chimei DAC-19M009 Power Supply problems

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

So I took a picture of it..

Pins in red are only connected with the transformator. They lead nowhere else.

S7-S8 725 ohms
S1-S2 1 ohm
S4-S5 1 ohm
S4/S5-S6 546 ohms
S1/S2-S3 546 ohms
S7-S3 358 ohms
S8-S6 366 ohms

[selldoor]

Re: Chimei DAC-19M009 Power Supply problems

Ok perhaps i see - You still need to look at each transformer as an individual.
I think the other secondary pin may be the pin at the right hand end of the row of 6 as in your pic - The two are connected so measuring across the two blues will be approx double the value so can you test S1 to pin 6 on one transformer and S3 to pin6 on the other.

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

Updated my post with some more accurate information.

[selldoor]

Re: Chimei DAC-19M009 Power Supply problems

Wheww!!! I think we got there and its good news ( well as far as the transformers are concerned. In your picture the secondaries are S3 to S7 358ohms and S6 to S8 366ohms - They are within 3 % of each other so they are good. I will have to think of something else!! Thanks for helping amraks, hopefully we can get you both fixed.

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

Okay, I did some magic which made me realize that mainboard is faulty.

I connected a computer PSU and buttonboard with the mainboard. It still had the flickering lights. This shows that LCD PSU had nothing to do with the clicking sound and flickering LED-s.

Now the question is - Is the PSU faulty too or just the mainboard?

http://www.ebay.com/itm/Main-Board-A...item3cc4b1c6c2 I was planning to buy this if it turns out to be faulty.

Now I will trouble Amraks a little so he could test something for me

[Amraks]

Re: Chimei DAC-19M009 Power Supply problems

what did you want me to test?

i just resembled the monitor to run it for a few hours.

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

I sent you a personal message.
Would be nice if you could test that out but if you don´t want to, I have no problem with that.

[Amraks]

Re: Chimei DAC-19M009 Power Supply problems

hope this helps anyone for later.

A guide capacitor map.

The_boss wanted to know the values of the capacitors.

So I done a diagram.

Thanks to all that helped me yet again.

[jh20]

Re: Chimei DAC-19M009 Power Supply problems

hey boss, any luck with your monitor yet? if you refer to my last post of this thread:

https://www.badcaps.net/forum/showth...?t=8349&page=2

you'll see that i'd just fixed mine a few days ago. but it actually died on me the next day with the clicking noise problem!

i'd just found the problem to my psu today and thought i might share it with you incase yours is the same fault. the 2 driver fet, part number p605, which drives the inverter transformer, one of them had shorted pins between the source and the gate.

try measuring between pin 1 and 2, then pin 3 and 4, of the 2 driver ic's and see if they're shorted.

edit: i do not have a replacement ic so i don't know if it will fix my problem completely but the clicking noise stopped after i removed the shorted ic. and the green light was coming on when i tried to switch it on.

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

It doesn´t show any sign of being shorted but I will try removing anyway. Maybe it has some effect.

[Amraks]

Re: Chimei DAC-19M009 Power Supply problems

Should I touch wood on this psu and hope to god mine don't fail too.

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

Maybe.

This is actually second time I fix this monitor. First time I only needed to change caps. A week later it stopped working again and I have not fixed it yet.

But now, when I removed P605 from circuit and tested them, I saw that one of them had S2 shorted with drains.
The strange thing is that when I tested it now, it did not show any shortage :S

[Amraks]

Re: Chimei DAC-19M009 Power Supply problems

i hope a better 22" LCD monitor comes up, then I can sell it.

I nearly paid 15 dollars for this non working crap. lucky I didn't have change with me and they was busy.

3.75 for some caps + 3 caps I had spare from other jobs.

I guess I done this one cheap.

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

The good news is, this LCD actually belonged to a customer who never showed up later. So I got it for free. And thus far I have not paid anything for parts.

Could somebody tell me what are good replacements for P605 mosfets?

[Amraks]

Re: Chimei DAC-19M009 Power Supply problems

how many months in your country do you need to give customers, before they have to come collect?

I know its 3 months here by law.

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

Should be 2-3 months if I am right but actually I am just an individual who just likes to work on electronics. I do not own a company yet so this law does not apply to me if I am right.

I could be called a stealer but police doesn´t even bother with it because the amount of money it is worth, is just way too small to move their pen

[Amraks]

Re: Chimei DAC-19M009 Power Supply problems

Ahhh I see. doing the same as me.

I used to work for a car wreckers that fixed cars also. I am pretty sure some of them cars were collected after 3 months.

have you got the data sheet for p605 mosfet?

[Amraks]

Re: Chimei DAC-19M009 Power Supply problems

http://www.ebay.com/itm/LOT-OF-2-AOP...-/320521760940

[RethoricalCheese]

Re: Chimei DAC-19M009 Power Supply problems

Nevermind about P605 mosfets. I found out that my PSU is working fine. The shortage I saw was a false alarm. The thing is..After I tested drain to gate, it opened source to gate so it showed shortage because of that. Everything is working fine now. Only the mainboard is broken, which I have to order from ebay.

So happy :P:P

I will make a new topic soon about the next monitor I have a problem with. Be ready

Anyway, thanks for the help!

[jh20]

Re: Chimei DAC-19M009 Power Supply problems

It doesn´t show any sign of being shorted but I will try removing anyway. Maybe it has some effect.

ok in that case maybe yours' different faults. if it's shorted it's very obvious as the pins will measure near zero ohm. i should have mentioned this earlier, it's much easier to isolate the inverter section by pulling out one leg of the glass fuse than trying to remove the ic's. try this instead to see if the clicking noise would go away.

edit: oops, i didn't scroll down my screen so i missed your last post, boss. so don't worry about this post then....

edit 2: amraks, if you still want the p605 datasheet, here's it is: