I know nothing about monitors....please help

[betacrash]

I just went to an auction this weekend and purchased a hodge podge galaxian cab. It's not really a galaxian cab....the only thing that resembles one is the galaxian board inside and that is it. The monitor that the person used on it is a big ol' 25" that is installed vertically. It does not even really fit in this cab....anyway. My problem is that I would like to use the monitor but it has an issue. When it is turned on it looks pretty good but after about 30 seconds the picture starts to shrink down to a horizontal line (right now it is installed vertically so it shirks down to a vertical line actually) . It is an RCA monitor, that is all I know of it right now. Does this sound like something that a cap kit could resolve (like I even know what a cap kit is or what it does)  or does it sound like something more serious. Any help would be appreciated. -betacrash

[MonitorGuru]

RCA doesn't make monitors, only picture tubes.  Look for a manufacturer name and part number on the metal frame or the chassis (circuit board)

You have vertical collapse. The horizontal deflection is still working as it's producing a horizontal line (when looking at like a TV orientation).  Since it shrinks down over time and isn't always collapsed, as long as it's a gradual shrink, it's probably not a bad solder joint or wire.  

I would suggest starting with what's known as a "cap kit".  This replaces all the aged and dried out capacitors known as electrolytics.  These cause numerous problems when they're old and could affect this.  However, while a cap kit is cheap (usually $5 + $6 shipping) you need to know how to safely "discharge" a monitor to remove the circuit board from the tube, and how to desolder and resolder components and how to read the markings on the circuit board to ensure correct replacement.

If the cap kit doesn't fix it, you may have other problems such as failed resistors or even transistors/diodes in the circuit, but that is less likely.

Even if a cap kit doesn't totally fix things, usually one done on a 20 year old monitor that hasn't had one done recently will bring back the monitor to looking and operating better in many ways.

[the3eyedblindman]

My computer monitor im using right now is from the early 90's, and sometimes the picture will start flickering and the picture will turn into a thin horizontal line, with 2 black spaces on top and bottom, is this what happens to you? I usually just beat the hell out of the side of it and it goes back.   Good luck fixing yours though.

[betacrash]

Thanks for the advice guru. I will try to find the type of the monitor. Once I get that, how do I get the correct cap kit. I have discharged a monitor before so I guess that is one thing I know about. But it still scares the ---steaming pile of meadow muffin--- out of me. -betacrash

[MonitorGuru]

3eyed: You probably have a cold solder joint... a place where the solder didn't fully set warm enough when being made and over time has broken free from the trace/post.   Whacking a monitor is never a good thing, but at least it probably is a mechanical and not a component issue, per se.

Unplug the monitor, crack the case and then look around for the yoke wires where they attach to the circuit board. Check for hairline cracks around the edges of where the posts plug into the board on the under side.  Even if you dont see any, reflow the solder with a 30 to 40 watt soldering iron .  Also check the other ends of the wires where they attach to the yoke itself. All that banging could have disloged one of them more there too, however the primary spot is usally on the main circuit board.

(Also follow the traces back from the yoke connector posts to at least the first if not second component past them, as the breaks could be there as well)


beta: Find the model number then go to http://www.therealbobroberts.com and find the cap kit page.  Most are $5 and he charges flat $6 shipping for the first couple pounds, so you might want to look around for other things to order too if you think you'll be needing them.