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tengugurl

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Hi all!
TL;DR monitor is missing red adjustment, picture is stuck on zoom/ things SRE overlapping not fitting the tube right.

More in depth:
1) bought this chassis working just lots of convergence issues,deep colors (working condition) but it had a lot of black goop leaking near or around the flyback
2) cleaned the goop up with 99%iso
3) recapped the board (I mean everything)
4) plugged it in, turned it on, (jamma mode first) and I got a very rounded picture with no red in the RGB balance
5) adjusted all the Pots on the chassis got it into a somewhat full screen (utilizing the real estate of the tube now) picture
6) noticed I was overlapping the image, almost like it was having sync issues?
7) tried vga mode, holly crap… talk about sync issues. It was not able to sync (garbeled picture) no matter how I adjusted the pic (almost like I am missing a h sync or h hold pot)
8) the monitor adjustment remote board has an up, down, and mode button that do nothing (I mean legit nothing. Well if you could making the picture wavy for a moment guess it does something)
9) bummed as it was working and now it’s not? I didn’t do a bad cap job


Any help you can give a girl out would be much appreciated ❤️

I love my candy cabs and this is the first time I have had issues post Cap kit. Normally it’s smooth sailing.


Pic 1 is vga mode being funky
Pic 2 is the jamma mode

Ps Avgn voice—- what were they thinking!? A red adjustment pot near grounded metal? (Aka under the vga daughter board) I had to do my best to not touch the metal while adjusting that pot
 

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Just curious. The remote board extension cable. If you wiggle the connector at the extension point will the picture come in and out? Mine has that issue. Sync will go in and out.
 
I've pretty much posted most of my answers in the FB group :), but for visibility here:

Your red gun, I would suggest reflowing the transistors as Omar has mentioned. I've had the exact same issue in mine and they work fine.
With the 2930, it's a manual sync, so I am assuming you have set the dip switches correctly for the 15khz/31khz signals?
As Anselmo has mentioned, with Pandora's boxes, you have to cycle through certain settings to get 640x480 (if it's compatible). Can you confirm the PB is completely operational outside of the monitor on the blast?

We also established that the monitor is a 2931 based on your remote board.

My blast fun and games have been documented here https://www.arcade-projects.com/threads/blast-city-resurrection.15109/ (going on the third blast now)

You said super zoom mode. Is that even when your hsize is at minimum? I had the same exact issue due to an aftermarket flyback

https://www.arcade-projects.com/threads/blast-city-resurrection.15109/#post-245100 and also here https://www.arcade-projects.com/threads/nanao-ms-2931.9238/post-154801

I have been told it can be fixed by adjusting the b+ pot but I wasn't too game mucking around with that. I didn't really know how to take a proper high voltage reading on the b+ pot
 
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Hi! Haha small world :)
So it’s gotta be something off with the remote board as I bought a kit for an ms2930 and all the caps lined up exactly. Attached a pic of the pcb.

I wonder how my friend had it working before if the remote board looked like this *pic2

The flyback looks OEM.
I cleaned up a bunch of black goop on it.
Oh are these the transistors that may need reflowing?

I reflowed them and no such luck, wonder if I should replace them?
 

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It does look like the 2930 (the green pcb - the 2931 is more like a tan colour)

That could be one of the issues you're having, you don't have the correct remote board. The remote board for the 2930 is like this (notice the dip switches top right?)

1639357314685.png


If your flyback is OEM, the superwide might be as a result of your "HSL" pot being turned way too much, you'll have to dial it down

I think first and foremost is to get the correct remote board and then see where you're at before replacing anything. Those are not the transistors, the transistors are the ones circled (with heatsinks), but you'll find the solder points to reflow are the ones with the red dot

1639357653755.png
 
It gets a bit wavy @sarty51
Tbh the buttons don’t do anything adjustment wise
Yea like the guy stated below you need a 2930 remote board. You have a 2931. 2931 will automatically select between 15,24, and 31. Your monitor doesn’t know what mode it’s in. I wouldn’t bother with any pots or anything till you get the 2930 remote board.
 
Awesome! Saves a lot of hassle! If you're still missing red after a reflow, it's beyond my skillet or knowledge :)

I send to experts haha
 
View: https://youtube.com/shorts/RYNwBB3j6VA?feature=share


Dang, reflowed the transistors and got the remote board to make sure I was set to 15hz.

Got it to show the neo geo mvs gridlines for a second then the text disappeared to a screen of red.

Lmfao! I was missing red and now I have too much.

Dialed down the red
Dialed down the brightness

Dang, any other thoughts or ideas?
Wonder if I can try more

Appreciate it thanks!
 

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did more research and it seems the transistors may be shorted and need a replacement … dang.
Does anyone know a part number? I need to check a manual or take one off to get a part number but curious if anyone had to do this before
 
When you adjust that screen pot I usually set my brightness pot to about the halfway mark on the remote board. That way you have some play. If your red is still to strong after dialing down the gain pot. You may want to check the big white resistor for that gun on your neck board as well. Also, what’s with that blue on the right half of the screen?
 
Also, assuming you've degassed too? It should do it on start up, but if you've got a degaussing wand or ring, that might also help
 
Latest update, bought new transistors installed them and black picture. Little grains but nothing on sync.

Bout ready to throw the towel on this and pop in a D9200 chassis I have as a spare.

Does anyone know someone or a company that fixes things “beyond the skill” of an adequate soldering person?
 
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