Blurry picture with supergun

ave · Post by **ave** » Tue Oct 21, 2008 8:06 pm

I just got a supergun last week, so I'm pretty new to the whole arcade thing. When then finally my first PCB arrived this afternoon, I tried it out and noticed that this what I was seeing there was definitely no RGB image. Bleeding colors, blurry text.

Here's a picture I took, hope it'll illustrate my problem sufficiently:

It's a selfmade supergun I won on ebay. By the way the RGB picture is absolutely flawless at times and sometimes, it changes to this blurry shit quality (only while actually playing the game btw, not during the Demo). Test mode looks RGBish too, no problems with the monitor test either.

Hope you can help me, thanx.

EOJ · Post by **EOJ** » Tue Oct 21, 2008 8:26 pm

aventus wrote:
It's a selfmade supergun I won on ebay.

Here's your problem.

ave · Post by **ave** » Tue Oct 21, 2008 8:38 pm

Probably...

Any guess what the problem might be? Maybe I can fix it myself.

Dragon1952 · Post by **Dragon1952** » Tue Oct 21, 2008 9:11 pm

If your SG is hooked up to a monitor, then your monitor is out of focus or some color is driving too hard or too little and needs adjustment. These controls are usually found on the monitor chassis or sometimes on a small strip circuit board connected to the monitor by a ribbon cable.

More than likely it is just the "focus" that needs adjustment. The focus is not found on the small pcb but rather at the rear of the monitor so look carefully for it there.

If your game cabinet does have one of those strip video adjustment pcb's find it and look over the adjustment controls. Slowly adjust all of them first slightly rotating on by one to see if there is a significant change or not.

If this is not the problem, then possibly it means that your SG has a video output problem (but I doubt that)!

If you are hooked up to a television (as the monitor) then maybe it is the TV's problem and it just can't handle the signal correctly.

Just some suggestions....

ave · Post by **ave** » Tue Oct 21, 2008 9:33 pm

Thanks for the suggestions, I'm gonna try to adjust the colors tomorrow.

The monitor is a Barco one and has seperate screws for optimizing each color. I don't know if that's the problem though as other sources show a flawless signal without any bleeding (Saturn RGB & PS2 RGB).

Dragon1952 · Post by **Dragon1952** » Tue Oct 21, 2008 9:38 pm

With that newer information that you did not mention before, I would deduce that the signal is flawed from the Supergun....

Strider77 · Post by **Strider77** » Wed Oct 22, 2008 12:14 am

it could be a grounding issue also.

Jet Black · Post by **Jet Black** » Wed Oct 22, 2008 12:50 am

It looks like the colors of the pcb are too strong. Some PCBs e.g. Cave or Psikyo ones have a stronger color output than other PCBs and Consoles. I would try to adjust the colors first.

Gwyrgyn Blood · Post by **Gwyrgyn Blood** » Wed Oct 22, 2008 1:05 am

What Jet Black said. Should be knobs to adjust the strength of the video output signal on the supergun and you might need to do that. You might have to open the thing up to get to them. If you don't have any knobs to adjust, you can always add some pots yourself which is not that hard to do.

ave · Post by **ave** » Wed Oct 22, 2008 1:38 am

Alright, so I tried to adjust the contrast and brightness and here's the result:

Crisp & perfectly colored RGB signal!

@Jet Black
Yeah, I think that was it. The colors were transmitted way too strong and vice-versa, i.e. the Saturn-signal looks pretty dark when I switch back again.

Thanks for your help, mission accomplished!

There's one problem remaining though: It's still Sonic Wings

Post by **system11** » Wed Oct 22, 2008 9:27 am

Sounds like you have a supergun without RGB pulldown resistors.

Strider77 · Post by **Strider77** » Wed Oct 22, 2008 10:47 am

your rgb cable for your supergun....

you need to add 75 ohm resistors to the RGB wires in that cord. that way you don't have to constantly readjust for your other systems and your PCBs.

Gwyrgyn Blood · Post by **Gwyrgyn Blood** » Wed Oct 22, 2008 1:46 pm

Alternatively you can wire up 1k Potentiometers to each line so you can manual adjust the strength, which is what I did.
That may be a bit less easy depending on the setup you have though.

ave · Post by **ave** » Wed Oct 22, 2008 2:26 pm

The supergun has an analog RGB output like this (bottom one):

I can't figure out where I had to add resistors, still inside the supergun maybe?

Jet Black · Post by **Jet Black** » Thu Oct 23, 2008 12:21 pm

aventus wrote:The supergun has an analog RGB output like this (bottom one):

I can't figure out where I had to add resistors, still inside the supergun maybe?

There or inside the SCART plug.

ave · Post by **ave** » Thu Oct 23, 2008 1:18 pm

In order to avoid such problems in the future, I just sold my supergun.

... and bought another, this time shop-made and with external rgb regulators.

Jet Black · Post by **Jet Black** » Thu Oct 23, 2008 2:54 pm

aventus wrote:In order to avoid such problems in the future, I just sold my supergun.

... and bought another, this time shop-made and with external rgb regulators.

From which shop?

I have a selfmade supergun, and made the modifications myself.

ave · Post by **ave** » Thu Oct 23, 2008 3:18 pm

I think it was called "arcade @ home", but doesn't exist no more (elends at triggerzone).

I'm not really into soldering and stuff, so I leave the serious work to guys who know what to do - for now, who knows what is yet to come when I'm getting a cab someday

shmups.system11.org

Blurry picture with supergun

Blurry picture with supergun

Re: Blurry picture with supergun