Help a newb with 3 issues

proto

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Hey experts!

Been tinkering with my arcade for a couple of years and got it to a decent (for me) state. I now want to fix any of the annoying things left that I can fix. Been reading up tons but clearly need some help adjusting my CRT and/or the Wei-ya 2628HR chassis. I've been pondering everything from adjusting the convergence rings (oh no!) to adding convergence strips to just messing with the red drive 😊

So, three separate (small) annoyances I'd like to fix

1) The edges have a weird pincussion-like effect. I "solve" it by stretching the image beyond the screen but I'd like to solve it. You can see it clearly here and to a lesser extent on the pattern
Pin issue.jpeg

Pattern.jpeg

2) I think this is recent. Tiny white dot patterns scan across the screen really fast. This happens all the time continuously
White dots 1.jpeg

White dots 2.jpeg


3) Colour bleed. This only happens with some games. Even with a pandora box some games are fine, others have excessive colour bleeding across all colours while some mainly get it with red. Pacman gets it worse
Pacman colour bleed.jpeg

and here's a couple where there's no bleed:
Mortal Kombat OK.jpeg
Pandora OK.jpeg

Would love any suggestions on things to try for each of these!

Thanks!
 

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No joy yet :( Either these are really tricky things or.. really bad questions! hmmm
 
What game is it?
What is the video output from?
Have you capped the monitor chassis?
Color bleed can be from to high out contrast/brightness/screen pot on flyback/ or RGB pot adjustments. Start by turning down contrast and brightness and see if it gets better.
Does the pincussion move in a wave like pattern?
Tiny white dots sounds like your screen pot on the flyback may be turned up too high. Turn down and see if it gets better
 
Have you done a cap kit on the CRT? That seems to solve many problems.

It sounds like you are using a Pandora's Box - is that correct?
 
What game is it?
What is the video output from?
Have you capped the monitor chassis?
Color bleed can be from to high out contrast/brightness/screen pot on flyback/ or RGB pot adjustments. Start by turning down contrast and brightness and see if it gets better.
Does the pincussion move in a wave like pattern?
Tiny white dots sounds like your screen pot on the flyback may be turned up too high. Turn down and see if it gets better
Hey!
These issues happen with many games, both PCBs (e.g. mortal kombat), MVS and Pandora 5S
Nope, haven't capped it (yet!)
Great, will look at the contrast/brightness
Pincussion - no, it doesn't move at all
White dots - roger that! Will report back :)
 
Have you done a cap kit on the CRT? That seems to solve many problems.

It sounds like you are using a Pandora's Box - is that correct?

Hey! You won't remember but whenever I've sought help around here you've come to the rescue :) thanks!

No, haven't recapped - but can do, its on the project list, especially if it may relate to these kinds of problems!

I do use a pandora box (5S), but not just that. the photos I shared are from pandora, Mortal Kombat PCB and the MVS test pattern :)
 
Hey! You won't remember but whenever I've sought help around here you've come to the rescue :) thanks!

No, haven't recapped - but can do, its on the project list, especially if it may relate to these kinds of problems!

I do use a pandora box (5S), but not just that. the photos I shared are from pandora, Mortal Kombat PCB and the MVS test pattern :)
Thanks. I don't have much experience with Pandora, but I think I have heard different games have different "drive levels" and that may be the cause of some of the problems you are having. Hopefully, someone who dabbles with Pandora's Box can lend some support or refute to what I think I have read.

A cap kit (assuming you have the skills to 1. discharge the CRT, 2. desolder, 3. properly resolder) is the usual action recommended. These CRTs are 30 to 40 years old. If it had any downtime in it's life, the capacitors can break down. Long periods of use with cheaper capacitors can allow capacitors to leak or swell, which can cause problems.
 
Thanks. I don't have much experience with Pandora, but I think I have heard different games have different "drive levels" and that may be the cause of some of the problems you are having. Hopefully, someone who dabbles with Pandora's Box can lend some support or refute to what I think I have read.

A cap kit (assuming you have the skills to 1. discharge the CRT, 2. desolder, 3. properly resolder) is the usual action recommended. These CRTs are 30 to 40 years old. If it had any downtime in it's life, the capacitors can break down. Long periods of use with cheaper capacitors can allow capacitors to leak or swell, which can cause problems.
Indeed. I'm fine with #2 and #3. #1 is on my list to dare over christmas (sounds straightforward to be honest).
So recapping it is! I'm struggling with finding a caps list for my specific chassis (wei-ya 2628HR) - I'm hoping I can figure it out :)
 
Indeed. I'm fine with #2 and #3. #1 is on my list to dare over christmas (sounds straightforward to be honest).
So recapping it is! I'm struggling with finding a caps list for my specific chassis (wei-ya 2628HR) - I'm hoping I can figure it out :)
Did you check Arcade Parts and Repair? He has cap kits for most monitors. He may be able to help you.

Look on Page 15 of his listing. I don't see that one.

Discharging a CRT isn't a dare. Get a reasonably long flat blade screwdriver or HV probe, and ground it with an wire to the chassis frame. Then slip the blade under the anode cap and gently push towards the bump or center of the cap until you make contact. Some of the time, you will hear a satisfying "snap". Pull the tip back a little, and then do the same thing until you don't hear a snap. Then remove the screwdriver and ground wire, and using a plastic putty knife or plastic tool, lift up the anode cap so you can see the connection.

I have seen two in my life - there are probably others.

There is the one I call the nipple and clip - it's a glass nipple that sticks up from the top of the tube, and the clip pushes sideways onto it. You pull the anode cap / clip away from the nipple to remove it.

The other is a spring clip that goes into a hole in the top of the CRT. You push down on the anode cap slightly, and then squeeze the sides at a 90 degree angle to the anode wire. You'll feel the spring tension, gently lift up and it should come out of the hole in the top of the crt.

Once you have done this, you can remove the chassis from the frame and get to work.
 
Super stuff! Indeed, not a dare but I'm sure I'll be extra extra careful the first time :)
I'm now considering just swapping this chassis out with one of two others I've got hold of - not sure which - i'll start a separate thread on that to get some advice :)
 
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