WG4900 Blanking Circuit Issue?

QuartrArcade

Active member

Donor 2011
Joined
Dec 16, 2005
Messages
1,110
Reaction score
15
Location
Pennsylvania
I've got two WG49xx 19" standard resolution chassis with the same problem. Basically just get retrace lines and white screen, which according to my research is a blanking circuit issue. I've tested Q201 and Q202 per the flowchart, they checked out fine. Poked around in the area, the resistors seem good, no burnt components.

Any advice here? I know the tube is good, I've tested other chassis on it.

Thanks,
Anthony
 
Bad C201?

There isn't much there. As long as the +15v, the base to Q201 has its signal, and the rest of the resistors are good, the only thing left is the black level pot.

If those all check good then replace the transistors. Maybe they are leaky?
 
Back
Top Bottom