DAC-19M009 Problems

[NickFi]

Re: DAC-19M009 Problems

@bradl450 -

Replace the rest of the caps. Not the big one on its side though.

Check the 2 transformers (side by side) with an ohmmeter and verify that their readings are the same.

@capn_chris - Resolder the transformer connections to the board.

Toast

Hi Toasty,
I've had my Chimei 22" monitor running since 2006 till 2015. It recently died (screen was getting black in a few minutes, then seconds). I found that some of the caps were totally bad - I have an ESR meter and they had an internal resistance over 100 ohm (while typically they are under 0.5 ohm). The big capacitor 120uF/400V was also completely stuffed (internal resistance over 100 ohm). After replacing the capacitors, the screen still turns off after a few seconds and I can hear some corona discharges in the inverter transformers (marked 28740001100 MB 633A). Now I am trying to apply some PCB laquer on the windings of these transformers - with some luck the shorted turns will get insulated.

Nick

[selldoor]

Re: DAC-19M009 Problems

Hi Toasty,

with some luck the shorted turns will get insulated.

You will need an awful lot of luck and it will probably do no good.

Have you tested the secondary wiring resistances. They need to be almost the same within 5% on both transformers. Perhaps post a good clear picture of your board
top and bottom