Donkey Kong Jr Monitor woes (horizontal hold won't stay still)

[8 1/2]

I recently scored a vintage Donkey Kong Jr. cab. It worked beautifully for a few days, but the horizontal hold started to go on me while playing. I opened it up, turned the horizontal knob to the right and it was fixed. That held again for a few days, but the problem returned. Over the last few weeks I've been having to open it and move that knob ever more to the right. Now, I've finally reached the end of the line (as the knob will move no more to the right) and I'm left with a screen full of lines.

Is this the death of the monitor, or is there some magic trick I'm missing? Has anyone seen this sort of thing in old nintendo cab with a Sanyo monitor?

One note: I've also tried a Donkey Kong board in the cab and it has the same problem, so I know it's not the pcb side of things.

[diskoboy]

Sounds like it just needs a cap kit. Does one side of the screen look like it's kinda folded in half? This tends to be a normal symptom with those old Sanyo monitors

Most of the old Sanyo monitors were supposed to have a shelf life of about 5 years. In an arcade enviornment, the capacitors on the monitor wore out faster because of constant use.

Re-capping your monitor is actually very easy if you have some electronics and soldering knowledge. But if you don't, have someone else do it.

And NEVER touch the anode, even with the power off and if the machine is unplugged - the anode is that little suction cup thing on the monitors tube.

[8 1/2]

When the screen is all lines, yes, there is a small section on the left side of the sceen that looks like it is being pulled down/folded. It makes sense then that it would look perfect with the horizontal adjustments but then just continue to worsen with time as it has? I've never done a cap kit before. Would I have to discharge the monitor to do it?

[Blur2040]

Yes, you do have to discharge it. Just be careful and you won't electrocute yourself.

The discharge is a bit scary, but I found the process of actually swapping out the caps to be fun and really quite simple.

[hayabusa_fmw]

before working with monitor be 100% sure about what you are doing

not 98.9% not 99.9%
but really 100%

if you have 1 doubt don't touch it!.

Read , read , or ask a electrical technician for info & help.
for safety measure , ect

[FrizzleFried]

The first time I discharged a monitor I was scared as HELL. It took me 30 minutes of standing on a blanket in rubber soled shoes with my discharging tool in my leather gloved hands sweating my ass off to finally do it. Once I did...(i was expecting a loud SNAP)...all I got was a "tink". Thats it. >TINK<!

It was so anti-climatic. The key to success is to ALWAYS use a SINGLE HAND to do it. Put your other hand in your pocket...seriously.

The cap kit itself is very easy to do once you learn how to use solder wick (flux)... practice on a dead board if you need to. Prior to doing my first cap kit, I'd never soldered on anything other than speaker wire...and i'd never even seen solder wick let alone used it.