Can a monitor be beyond degausing?

SilverDuck

New member
Joined
May 27, 2009
Messages
2,389
Reaction score
18
Location
Minnesota
Nanao MS8-26U. It will not degauss, and it needs it, BAD! There is no black, just purple/yellow/green, and all sorts of tie-dye goodness. No black. None. There is no degauss button, just the two wires. Touching the two wires together momentarily does nothing.

This is in a Sega Sky Target, which is the same cabinet as the Daytona USA sit down. How do they keep those two speakers on each side of the tube from messing with the monitor?

Any help? The game is unplayable...no black at all.
 
I have no experience with these monitors, I'm fortunate that the degauss switches all work on our Daytonas, lol.

is the actual degaussing coil plugged in? I don't know how the switch works but I would think touching the wires together would trigger the coil. you can press and hold it, but that kinda just scrambles it around more, it needs to be like a one good press and done.

I don't know how bad these are for cold solder and such, I don't think they're known to be that bad, but maybe the pins on the degauss coil too should be checked? I don't know.

need some Sega junkies to chime in.
 
Yup...tried manually degaussing. No good. I've never seen one this bad. On the test menu, where the background should be black, mine is purple and tye-died. I'd guess the game would be fun on LSD, but unplayable otherwise.
 
You need to wire that degauss button. As soon as it's wired and you bush the button it will fix itself. Trust me.

Here's a rough drawing of how to wire it. This is how I wired mine and another member here used this pic to wire his. Both worked great afterward. These MS8's absolutely need the manual degauss to be wired.

Before I forget, here's a little salt for that Sky Target wound. :D
picture.php
 
Last edited:
A monitor with the convergence rings out of alignment can look like that, ALSO, a picture tube can be bad in that the color mask inside the tube can be damaged, like if its hit hard or dropped (but survived).

I used to use a junk computer monitor when I fixed computers that was dropped down a flight of steps - nice big fat rainbow across the picture, but still plenty useable.

And despite the fact that someone just told me to use it - I got all sorts of flack for it :)
 
Also, if you lose the wedges and the yoke shifts too close to the tube, then the picture will be very colorful whether a board is connected or not...
 
Yeah, check the neck and make sure the yoke and color rings look like they're in the right place (pay more attention to whether or not they're slid far enough up the neck, not how they're twisted). I've had several that had permanent degaussed areas, like said above if that metal screen inside them gets bent you're screwed.
 
You need to wire that degauss button. As soon as it's wired and you bush the button it will fix itself. Trust me.

Here's a rough drawing of how to wire it. This is how I wired mine and another member here used this pic to wire his. Both worked great afterward. These MS8's absolutely need the manual degauss to be wired.

Before I forget, here's a little salt for that Sky Target wound. :D
picture.php

Nanao does not use an iso. It just has a connector coming off the chassis that goes to a momentary-on switch inside the coin door. By looking at that picture, are you saying I need to send 110AC (momentarily) to the degauss circuit?
 
The shadow mask inside of a monitor can be magnetized so badly that it cannot be demagnetized with a coil.


Try reorienting the cabinet to see if that has any effect.

That degaussing coil won't do anything until activated.

The purity rings can have an effect too. The pair closest to the tube face is used to set the purity. You will probably have to adjust the convergence if you mess with these though.

Kerry
 
Nanao does not use an iso. It just has a connector coming off the chassis that goes to a momentary-on switch inside the coin door. By looking at that picture, are you saying I need to send 110AC (momentarily) to the degauss circuit?
Yes, send 110AC through that circuit. As far as the monitor using an iso I was under the impression this monitor required one. The cab which I have that use them all have iso's in them. They are all Sega cabs. My Sky Target also uses an iso for the projection monitor though. I thought this was a bit strange but it has one, a very large one.

The wiring diagram I drew for the manual degauss button is the same as the actual wiring of the cab this monitor is in.
 
Last edited:
Yes, send 110AC through that circuit. As far as the monitor using an iso I was under the impression this monitor required one. The cab which I have that use them all have iso's in them. They are all Sega cabs. My Sky Target also uses an iso for the projection monitor though. I thought this was a bit strange but it has one, a very large one.

The wiring diagram I drew for the manual degauss button is the same as the actual wiring of the cab this monitor is in.

I shot some 110AC into the degause circuit, and it seems like that solved it. It still needs some fine tuning, but it's 99% better.

Thanks to all who replied. I'm not sure where I'd be without you guys!! Thanks thanks thanks!
 
I've seen monitors (computer) that people dropped that had bent shadow masks that caused what looked like magnetization issues that weren't fixable, but that was more localized than what you're seeing.
 
yeah me 2 i had a makvision, brand new that was dropped in transport HARD on one corner. It acted liek the yoke neede dto slid in more but couldnt because it was bottomed out on the tube.. i ended up scrapping the piece o krap. best guess was that the posphor screen inside was warped/bowed due to impact. nowadays i know enough that i woulda tried to tubeswap it.

glad the 110 trick worked for ya.
 
Last edited:
Hi every one, I am having the same issue with my monitor.
I have been looking around and can't find, a how to wire a manual degauss button for nanao ms8-26.

If anyone has a wiring diagram or a how to, it will be much appreciated!
Thanks
 
Don't worry - @thegleek doesn't bite. Usually.

The Nanao's are less common, so there might not be as much direct experience/tips/trouble logs around here as you might find for the more common monitors. But degaussing kinda works the same on pretty much all CRTs. Try the common things (move the game/monitor to a different spot, manually degauss, etc.). If you still have a problem, some pictures of what you're working with might help. Both the screen and the back of the monitor...yoke, rings, chassis, degaussing ring, etc.
 
Thanks for the reply @brokentoken
I have moved the machine to a different spot, I adjusted the yoke and the rings.
I even re-taped the degauss coli that go's around the tube. the chassis has been recapped.

When I moved the machine next to a power strip thats when it all went bad. since then I have it in a new spot with no interference.
 
Back
Top Bottom