JAMMAfied Genesis, video too bright... pic inside

[HornheaDD]

I bought a JAMMA Genesis from a friend and hooked it up to my cab, and the brightness (or contrast? I never know the diff) is way up high. When I turn it on, the "Licensed by Sega" screen looks white with white text. The video looks fairly crisp, its just wayyy to bright (check the pic).

Now, with my Neo 4 slot and a MGCD set up I have, video is perfect color/brightness, so this tells me its the Genny. Anyone know if this is a common issue with JAMMA Genesisesesessse?

Shit.

I think I just realized that my monitor might be needing repair. Apparently the brightness was pretty damn high. If I adjust the brightness to use the Genesis, and then try the Neo, the Neo is SOOOPER dark, to where you cant even see the border for the UniBIOS menu.

Fuck. Who in this day and age services arcade monitors?

 

[SignOfGoob]

Wait...I’m totally confused. You have two boards with one brightness level and another that is much brighter and you think the monitor is the problem? I don’t know what a MGCD is but there are for sure a large range of brightness from arcade boards over the years. Neo and CPS are about the same but when you change through a bunch you’ll find the brightness varies a lot so this sounds normal to me.

Someone converting an Genesis to JAMMA...also ads to the confusion. I just don’t get that at all.

 

[ggallegos1]

See if Lemony Vengeance can help out, he's jammafied a lot of consoles in the past and may be able to point you into which resistors are needed and where

 

[DaisyAge]

You could try adding like 2k pots to the RGB lines and turning the resistance up should lower the brightness. Could you get a voltage reading of RGB and sync off the JAMMA edge for us?

 

[HornheaDD]

Wait...I’m totally confused. You have two boards with one brightness level and another that is much brighter and you think the monitor is the problem? I don’t know what a MGCD is but there are for sure a large range of brightness from arcade boards over the years. Neo and CPS are about the same but when you change through a bunch you’ll find the brightness varies a lot so this sounds normal to me.

Someone converting an Genesis to JAMMA...also ads to the confusion. I just don’t get that at all.

Hm, maybe so. It just concerned me because the whole time I had the Neo, an old Pandora shitbox, and now the MGCD* I never messed with the brightness pot. But evidently it was turned nearly all the way up the entire time. Ive had the cab for like 10 years and never had to fiddle with the brightness. Its just concerning to me now that maybe my monitor was dim.

I dunno.

@DaisyAge, I can try to do some sometime today. As for adding pots, I'm sadly not that familiar with rewiring stuff. I'm pretty basic when it comes to soldering and whatnot.


@SignOfZeta - *The MGCD is basically a JAMMAfied Dreamcast casing. I'd say check out google on it, but there's literally not much info on it other than this random dude's Blog post: https://arcadefever.blogspot.com/2010/09/hacking-mgcd-part-2.html

 

[DaisyAge]

You just need to solder a potentiometer to each of the positions on the edge. Usually they have 3 legs, you'll only need to solder 1 to the edge and the other leg to the wire going out to the monitor.