Hantarex Polo 25" problems

[finerion]

Hello there everyone! First post here about my first cab acquisition. I am working with a Mortal Kombat III Ultimate conversion of a MK II cabinet using a Hantarex Polo 25" monitor. The board, controls, and sound are all working great but I am having a few issues with the monitor:

1. The monitor slowly fades to black after about 4-5 minutes of being on.
2. The only colors coming through are red and black. When I adjust the green upwards even a little the entire screen is washed in green. When I attempt to adjust the blue I have to turn it all the way to max before any blue comes through at which point the screen is all blue. I have attempted numerous adjustments and tweaks to all of the controls including contrast and brightness (both of which have to be at max before I can see anything) with no good results.
3. The degaussing wire connector was missing from the harness and I have just finished soldering a replacement from the spare harness that came with the cab but still no change in the machine's status. I am left with one connector, however, that I cannot seem to figure out what it goes to or where to plug it in. It is a single black wire that seems to run next to the degaussing wires.

I'm uploading a batch of pictures showing as much detail as I can of the harness and monitor. http://www.flickr.com/photos/alfredbonnabel/sets/72157613374926139/

Any thoughts on what could be causing this and what I could do to fix it?

Thanks,

Alfred

[grantspain]

sounds like 2 of the colour drive transistors are breaking down when they get hot,which is a common problem
also do you have the dag earth connected to the neck card
oh just re read yes you need to connect the single black wire from the dag earth(earth braid) to the neck card spade terminal

[finerion]

Got the dag earth plugged into the neck card and now the picture stays on! Yay!!

Now that I have had more time to try tweaking the pots I'm still at a point where the screen has an overwhelming blue tint with just some vague redishness. The game is playable but it is very distracting.

Incidentally, I seem to have lost the ability to select any of the hidden characters and I cannot seem to enable them in the service menu. 

Any other suggestions?

Alfred

[grantspain]

stick with the monitor for the time being,
the colour hues you are seeing are down to the background colours being set too high
there are background pots on the neck card,you need to adjust them

[finerion]

The pots on the neck card are what I have been adjusting. I have not found any color-related pots on the harness itself. Everything there seems to be related to contrast, brightness, sync, etc.

 

[grantspain]

you sure you are doing it correctly,
turn all the cut offs to near minimum
turn you gains down
turn your contrast and brightness to mid way and then adjust the screen volts up/down to get the brightness at reasonable level
then bring up the gains

[finerion]

Been tweaking it for the past hour and still nothing. Only seem to get any blue or green when it is turned to max and then the screen is almost completely blue/white or green/white.

Alfred

[grantspain]

now you will need to check out the pots,drive transistors and ic1
it could just be the pots knackered

[finerion]

I don't suppose you happen to know a link where I can find info on how to test those components. I'm trying to do a google search but nothing helpful seems to be coming up.

Thank you for all of your help.

Alfred

[grantspain]

well you would need an analogue multimeter to read the pot action correctly,it can be done with a digital multimeter but its not accurate
the transistor will need to read using a multimeter,if they are leaky you can not prove that unless you put new ones in
the ic would need an oscilloscope and you would need the expertise to use one
so your only real option is swap all the possibilities or get it repaired by someone