Nanao MS9-29T screen shuts off

[Wurstkopp]

I have an Egret 2 with a Nanao MS9-29T chassis here. Today I changed the lamp and unfortunately a screw fell on the chassis and must have shortened something (I later found the screw lying near the flyback):



Don't know if that has do with the problem, I found several screws on the chassis, in fact all screws that fall into the machine seem to fall directly on the chassis. The problem is: If I now turn on the machine the screen only shows some white horizontal stripes. The whole screen gets brighter and brighter and then it shuts off.

Heres a Video:


http://www.youtube.com/watch?v=UaYSXqzlT50"


Any ideas how to fix this? I have a multimeter and know the basics to use it.

[grantspain]

check any diodes near that flyback

[Wurstkopp]

D507 (the one right above the yellow circle) says 4,8 ohms in both ways. I guess this one's not doing well?

[grantspain]

D507 (the one right above the yellow circle) says 4,8 ohms in both ways. I guess this one's not doing well?

thats probably just reading the ciruit,you need to desolder one side to meter a diode-normally when faulty they read dead short even in circuit

what you really need to do is isolate the flyback from the circuit and read the b+ to make sure thats stable

[Wurstkopp]

Okay, I desoldered both sides of the diode and measured again. This time the multimeter showed no reaction (measured from both sides), so I guesss it's faulty. Any ideas of the specs of the diode? Damn thing is too small to see anything...

Isolate the flyback..? You mean desolder the whole thing and then read the b+ on the chassis?

[grantspain]

Okay, I desoldered both sides of the diode and measured again. This time the multimeter showed no reaction (measured from both sides), so I guesss it's faulty. Any ideas of the specs of the diode? Damn thing is too small to see anything...

Isolate the flyback..? You mean desolder the whole thing and then read the b+ on the chassis?

1dl42a
http://www.datasheetcatalog.org/datashe ... a/3561.pdf"

when i talk about the isolation of the flyback that means desoldering the pins for b+ and horizontal output transistor,then add a lightbulb 230v to across b+ and earth to give the circuit a load-then ou can read the b+

[Wurstkopp]

Wow, thanks for the explanation . I have attached a highres pic, could you tell me which pins I have to desolder?

[grantspain]

pins 1 and 2

pin 2 is b+ i think

[Wurstkopp]

Thanks, Grant