I'm in the process of consolizing a Neo Geo MVS, the joysticks work, but there is something wrong with the picture?! I tested all solder joints, measured everything with a multimeter.... i don't get it, everything seems to be connected right.
I am located in Europe, so i use SCART and direct RGB.
Is the board busted? maybe someone here can help me.
Thank you very much!
http://www.youtube.com/watch?v=TF7urjk9iW8 (turn the volume down first, it may be a little loud, sorry)
http://girugalol.mybrute.com
When the doctor asked me, if I heard voices in my head, the voices said "tell him no!"
Have you used this TV before for arcade games?
nope, actually mvs is my arcade debut.
http://girugalol.mybrute.com
When the doctor asked me, if I heard voices in my head, the voices said "tell him no!"
wish I could help you but mine's running through s-video so we don't have scart out here. Does the blanking signal pin have the correct voltage?
Arcade RGB levels are a lot higher (1 to 4.5Vpp at 1K ohm) then what scart TVs are used to (0.7Vpp at 75ohm).
For a start check to make sure you have wired up ground to at least Video Ground (pin 18). Also make sure you have a 100 ohm resistor between +5V and Pin 16.
If you have or it doesn't make any difference then try putting a 300ohm resistor between Composite Sync and Pin 20 of your SCART cable and see it that improves it. If the colours are still too bright put 75ohm resistors between the Red, Green and Blue pins.
Also don't connector audio from a Supergun to a monitor unless you have attenuated the audio so there is no chance of you blowing your TVs amp. If possible use a seperate speaker.
A lot of build your own supergun pages are pretty poor when it comes to SCART and arcade monitor levels...
Last edited by Jamtex; 05-18-2009 at 08:15 AM.
Looks like all my Genesis-s (Geneses*) do when I hook up a shit chinese power supply.
I second the notion of a simple signal output level, however.
Last edited by alecjahn; 05-19-2009 at 09:18 AM.
I AM A MONSTER TRUCK THAT WALKS LIKE A MAN
(╯°□°）╯︵ ┻━┻
........Originally Posted by alecjahn
what does a power supply have to do with video sync?
done all that, its still the same.
i wish i had another supergun and another arcade board for testing.
Last edited by alphagamer; 05-19-2009 at 06:28 PM.
http://girugalol.mybrute.com
When the doctor asked me, if I heard voices in my head, the voices said "tell him no!"
Try on another TV to see if it's a problem there, the fault looks either like a grounding issue (make sure you do have good grounds, connect up all the grounds on the board to the PSU and make sure the SCART cable has Video Ground connected to Video Ground on the SCART and for luck stick a ground to the Audio Ground) or a level issue.
Stick a pot of at least 1K (try a 5K too), between the Sync and SCART and do the same for the R, G and B lines. Adjust with the aid of a multimeter to see if improves the picture.
Is your scart cable shielded?
I'd check the ground pin in particular and that you have 21 (the plug shield) connected to ground as well
I have had some success removing unused pins from home-made scarts. Assuming it is the standard home-made kit, they should just clip out
If you have ferrite beads to hand, I'd put one at either end of the cable
Have you seen mmmonkey's guide to MD/Neo-Geo Scarts? It may help...
http://www.mmmonkey.co.uk/
tested on 2 other TVs (all the TVs support RGB, says so in their manual, and i tested it with other input sources) still the same.
i will take the whole thing apart and start from scratch.
thank you all!
sincerely,
the arcade noob ^^
http://girugalol.mybrute.com
When the doctor asked me, if I heard voices in my head, the voices said "tell him no!"
You know, I have no idea. Some of them just have a nice white line that goes up, and it looks like crap. The best one has a bad audio hum. The rest jump video every 10 seconds, it'll scroll up. Maybe there's something wrong with those particular systems which is being multiplied by the crap adapter. I've made a separate thread for this matter.
Last edited by alecjahn; 05-20-2009 at 03:43 AM.
I AM A MONSTER TRUCK THAT WALKS LIKE A MAN
(╯°□°）╯︵ ┻━┻
If the power supply is unregulated or has poor filtering on the outputs then you could have strange effects ranging from audio hum to picture problems to outright crashing/dying.
It's more likely that you are overdriving the inputs on the display or your display doesn't like the sync rates of the Neo Geo board.
My repair logs are kept on the NewLifeGames.net website. I hope they help you keep your system running for years to come.
its alive!
its working!
the problem was: the diagram i was working with was not correct.
now that the tech side is perfect i can move on to finalize the casing.
http://girugalol.mybrute.com
When the doctor asked me, if I heard voices in my head, the voices said "tell him no!"
diagram? jamma to scart is just like..straight wires isn't it?
anyway the case looks cool from what I can see in the video. Mind posting some nice pics of what it looks like?
Last edited by drakon; 05-21-2009 at 05:42 AM.
the diagram on the website had some contacts on the jamma pinout labeled incorrectly.
so true, oh so true...
Last edited by alphagamer; 05-21-2009 at 05:44 AM.
http://girugalol.mybrute.com
When the doctor asked me, if I heard voices in my head, the voices said "tell him no!"
oh I approached the whole building of a supergun thing differently. I started with the angle of "how the f#$% does it work?" and from there managed to make a working one on the first try. Luckily it's a pretty straight forward piece of hardware. Also what are you using for a power supply?
Was it one of the ground pins not be connected properly?
yes, and the sync pin was labeled as on the upper connector and the blue pin on the lower, hence no blue.
pretty f'ed up diagram...
http://girugalol.mybrute.com
When the doctor asked me, if I heard voices in my head, the voices said "tell him no!"
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