Weird problem with an old-style 1084 monitor.

[Zordar]

Hi,

I'm wondering if anyone can shed some light on this strange problem I'm having with this monitor.  This is a Commodore 1084 (old style) monitor which developed an issue with the display, putting it simply, as you pass the mid-point of the tube (going from the bottom up), the scan lines get further & further apart. By the time you get to the top of the screen, you have about a 1/8" gap between the scan lines.

I presumed that I'm dealing with a bad cap, and already replaced all the major caps, but still did not resolve the problem.  The question is, is this a "bad capacitor" situation, or a completely different issue all together?

Thanks.

[spaceman88]

Hi,
Did you change the caps around the vertical output stage? I don't have a schematic for the 1084, but on a T.V. it's often a small cap (2.2, 4.7,10 uF) near the output IC (or output transistors on older units).



I'm wondering if anyone can shed some light on this strange problem I'm having with this monitor.  This is a Commodore 1084 (old style) monitor which developed an issue with the display, putting it simply, as you pass the mid-point of the tube (going from the bottom up), the scan lines get further & further apart. By the time you get to the top of the screen, you have about a 1/8" gap between the scan lines.

I presumed that I'm dealing with a bad cap, and already replaced all the major caps, but still did not resolve the problem.  The question is, is this a "bad capacitor" situation, or a completely different issue all together?

Thanks.[/QUOTE]