Big Red Monitor(Red Cap) Issue

[chris1]

Big Red Monitor(Red Cap) Issue

Ever since I moved this cab from one apt to another removing the Monitor to do so I have had two issues..
One the mem card reader cables one creates lines on screen ,all my grounds are on but if I plug in the left mem card reader cable on the board I get interference on screen...I figure one of the wires within the wrap is touching another.if I unplug the mem card cable the interference goes away.

I don't play the cab as much as I used to but ever since the move I started to notice a blinking on screen of color loss-background variations..It seems I keep losing the RED..It comes and goes but is agravating..Cleaning games,boards,harness connector to board nothing changes it..

My monitor remore board pots are touchy but they make no change to the color variation.
So I went into the Hardware test..at first everything was ok,the background was Black then it blinked to this..(the reds gone)

Pay no attention to Flo on screen as that's the reflection of my TV..

So I adjusted the monitor)bright,contrast) on it's remote board and no change..If I leave the monitor in Hardware test the Black backgroun will show up,blink to it and you'll see the red box again..

If I leave the xab on for like an hour sometimes I don't get any loss of red..then sometimes I do..Last night I had the cab on for 2 hours and after he first 30 minutes of play or demo I never lost the Red..

Due to this I figure maybe the red cab has a Dry Solder joint?

What do you think?

What should I do..?

Do a cap kit?(never done but will attempt)

Re solder the red cap solder points?

Not sure where to get the caps so I have to go look to see what monitor is in it.

If I was to do a cap kit can someone lead me to what I should buy in a soldering iron,solder etc.. and what I'd need to do the job..I have the hands to do this kind of work justt need to know what 'd need to do the job..

Should I pull the monitor and remove the chassis or do a cap kit with the chassis still connected to the tube?

 

[malignantpoodle]

I had a very similar problem on mine. Colors in and out. Sometimes I had no red, or green, or whatever. It would just look nasty a bit like yours (actually worse than yours) and it was intermittent.

I currently have caps on order, not knowing for sure if that will fix the problem (but will update after the job is done). As far as which caps, really need to see the board. For me, nobody could really identify my board so I just went through and examined every cap on the board to know what to get. Like me, you might want to replace every single cap while you have it out instead of just one that you suspect.

You can likely do the cap kit with the tube still in the chassis. I was able to remove just the board once the whole setup was yanked from the cab.

If you've never done soldering before, be careful. While it's easy to learn, as a beginner it's also easy to mess things up, usually on the order of burning out traces or making bad connections, cold solder joints, and the like.

I'd get a 40w pencil tip soldering iron, thin rosin core solder (skip the lead free stuff, it sucks), wicker wire (solder debraid), and of course the appropriate capacitors. As far as how to solder property, you can google or youtube "how to solder" for tips. I know that Ramsey Electronics sells a kit for like $5 that teaches you the basics and has you practice soldering. I personally would not feel comfortable for my first time replacing components to be doing it on something like this. Either the Ramsey kit or some careful reading and video watching and maybe practice on a clock radio. Remove componenets, reinstall, see that the radio still works, until you get it right.

 

[Dion]

Here's what you need to do. No a cap kit probably won't fix this. You need to remove the chassis and resolder ALL of the header pins on the chassis. They are the pins that the connectors push onto. Remove the old solder and flow new solder onto them. It is common for solder to crack on all monitors at the headers.

After you do that look at the neckboard. There are three identical transistors on it. they correspond to the color drive circuits. Reflow the solder to these transistors and then test the chassis.

If your color hasn't returned you may have a bad transistor. It could also be a bad gun on the tube but since the color does work sometimes that is most likely not the case.

 

[Hewitson]

Almost definitely the transistor for red on the neck board has dodgy solder joints.

 

[malignantpoodle]

UPDATE

Here's what fixed mine with the identical problem;

resoldered the joints of the pins where the wiring harness RGB Sync connected to the board. Removed the old solder (joints looked just fine but desoldered anyway), and added new joints.

Problem solved 100%

 

[Dion]

UPDATE

Here's what fixed mine with the identical problem;

resoldered the joints of the pins where the wiring harness RGB Sync connected to the board. Removed the old solder (joints looked just fine but desoldered anyway), and added new joints.

Problem solved 100%

Awesome! My advice didn't fall on deaf ears. lol.

 

[malignantpoodle]

Yep, you certainly called it.

Now if I can get the "waviness" out of the monitor. The screen appears to be moving slightly back and forth, but it's hardly noticed unless you're on a static screen. Have a solution for that?

 

[sammybean]

Yep, you certainly called it.

Now if I can get the "waviness" out of the monitor. The screen appears to be moving slightly back and forth, but it's hardly noticed unless you're on a static screen. Have a solution for that?

I've got the same issue m'friend .

 

[chris1]

Yep, you certainly called it.

Now if I can get the "waviness" out of the monitor. The screen appears to be moving slightly back and forth, but it's hardly noticed unless you're on a static screen. Have a solution for that?

If you have a seperate monitor adjustment pot board(mines located under the CP) I'd check the pots..My pots are touchy and one if bumped creates a wave on scren so I wear it in by moving it back and forth,I wonder if there is a cleaning process to fix this problem..

.

And thank you everyone.
I will update the topic once I get it done and all the stuff I need,practice kit etc..
Thank you for all the info..

 

[Dion]

Three things it most likely could be.

1--a bad ground connection on the chassis.

2--B+ voltage needs to be tested and adjusted. Bad B+ can cause the video to "HULA".

3--Noise on your switching power supply. Common on older switchers.

It could also be something as simple as tweaking the Hold pots or more complicated like a filter cap being out of spec. I have a test cabinet and some of the pcbs I use have wavy lines and others don't. If it happens on EVERY pcb start by checking voltages on your PS and then check the above list.

 

[neogeogod]

hmmm this seems to be happening on my 4 slot I'm kind of a soldering nub could anyone post some pics on where exactly on the board i would need to solder with pics? mine isn't perma... yet. i hope it doesn't but if i don't play it for a few days and turn it on it blinks red then goes solid for a minute but it always snaps out of it

 

[chris1]

UPDATE

So we've been using the cab a lot lately and it's been fine..I have a party coming up on Sat and I wanted to cherck out how the cabs working-if I'd change any games for the party..

Upon turning on the cab he screen was all BLUE...oooouuch..Turned the cab off then back to red..

Frustrated,and in need to get this fixed before the party I was just about to turn the cab around,and or pull the monitor from the front..
I decided to open the control panel and look at where the monitor plugs into everthing,board etc..I ran my hand up along the left inside of the cab to find the wire that goes from the board to the monitor and the monitor started to flicker..the color straightened out....huh....I moved it around some more and I'd lose red etc..
I found the 4 pin?) molex plug...The molex plug wasn't pushed all the way in together..

As son as I did that the monitor went back to normal..no more flicker or loss of color.

Seems fine so far..
If this was the problem then I've had a very good day..

 

[LWK]

Shit, good thread.

Okay my green issue may be similar. It starts up that way, and I noticed for a transistor some solder had cracked off and one joint looked completely removed. I did this also. I reflowed the three joints for the transistor, but now I'm wondering if the transistor itself might just be bad. I had another small pcb with a transistor, and 2 or so caps on it which was originally screwed into the chassis. Somehow it became unscrewed and this white acidy type glue was in the spot it became lifted. I just screw it back in, but i'm wondering if it blew off the chassis when I fucked up a previous psu or something.

Would a transistor regulate a issue of power flow for a greener screen at start up? It looks perfect after a few mins, but I have two questionable transistors.

 

[Dion]

Whenever you have a missing color, etc. You should reflow the solder for the pins that the connectors plug onto. Its common for them to have cold solder joints.

When a transistor goes bad it usually goes open so you lose the color completely. Your warm-up issue could very well be an issue where one of the color guns in your tube needs to warm up more than the others. Someone with a tube rejuve/tester could tell you.

With all monitor problems you should:

1st: cap kit (if not done recently)
2nd: reflow all header pins (go ahead and do it while you do the cap kit)
3rd: troubleshoot remaining problems individually
4th: check various common faults known to affect said monitor
5th: if signs point to the tube--crt tester (least likely)

 

[LWK]

You know someone who's more skilled at this? I installed some caps on my mvs board, but touching that chassis just bugs me. I'd rather someone with long term experience do it.
It sounds like a bad gun, and I think i'm fucked.

 

[ttooddddyy]

The missing red is intriguing. Without the red the whites would otherwise be yellow.
There is more to this than meets the eye. looks like a fault on the mobo not the monitor. Try another board and put another log on the fire,

 

[chris1]

Bumping my old thread ..as I fixed the issue a few months ago..

also>
In another thread I made=I was having issues with interference lines from the Memory Card board reader cables...(Memory Card board reader cables to the 4 slot mother board interference.
http://www.neo-geo.com/forums/showthread.php?t=198061

>>>
.............................
A few months ago I was moving the Memory Card board reader cables around with the cab on trying to locate where a break in wires or ground problem was when I noticed the cables lie bumping another main wire that goes from the motherboard to the monitor..When I lifted the wire that goes from the motherboard to the monitor it started to cause the color fluctuation/loss or Red...
I traced that wire that goes from the motherboard to the monitor along the left side of the cab and came upon a Molex Connection(4 prong) and found that it wasn't pressed all the way in..With a general feel it felt ok but upon putting more pressure/pressing the molex plug together harder it had more to go..This solved the "problems" I was having as a few days later I plugged the Memory Card board reader cables back in and no more interference..

What was going on was,when I'd pull the Memory Card board reader cables out of the motherboard they'd no longer push-pull on the Molex Connection wire going up to the monitor from the motherboard when I opened up the control panel so I figured it was the mem card cables that were the problem when all the time it was just that one wire(Molex Connection) going from the monitor to the motherboard..

I am sooooo Glad my Baby is working great again...

................................
I almost went out and bought a new monitor,and or tried a spare I have in the basement..