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kingau

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Hi everyone
I just re cap my chassis,
and replaced
R432 (8.2k)
(R433) (2.2k) - keeps burning up!
R435 (12k)
R436 (15k)
R445 (8.2k)
And a new flyback.
My +B volts is adjusted to 92 volts.

Does anyone know the fix for this ?
Or have had the same issues with the nanao ms8-26su chassis?

Thanks
 

kingau

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check q401 and 402
check any diodes around that circuit
checked both, they are in working order.
I had replaced Q401 and Q402, thinking it was that I put back the old ones back and still the same issue.

the monitor works fine but, there are lines at the top of the screen, and R433 still burns out.
I'm thinking it's the bad soldering job that was done on it, will post pictures of the bottom.
 

kingau

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Pictures for the area...
Caution this is not for the faint of heart!
pic 1.jpg
pic 2.jpg
 

kingau

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it was not,
it work ok, but on start up it would go bright then dark... and stay dark.

after that I changed
R432 (8.2k)
(R433) (2.2k)
R435 (12k)
R436 (15k)
R445 (8.2k)

and that's when r433 started burning up.
 

gunblade

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ok i reckon you have a bridged track around that area- i would desolder those components around r433 and clean the circuit board and then look for broken or bridged tracks.

your original fault was likely only a couple of caps and possible bad solder joint on the crt socket
 

kingau

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I have been working on the chassis,
and noticed for some reason R433 is connected to C on the board

C is connected to ground... is this right?
the reason I ask, is because I disconnected C and noticed I didn't get and connectivity to R433 and the whole line with it.
but when I solder C back I get a bit of connectivity.


Does C go to ground?
here's a pic of what I am talking about.
 

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kingau

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I didn't, I bought a old nanao ms8 26u chassis and cap it.
My old chassis had so many lifted traces!
 
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