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Main => Main Forum => Topic started by: duhh on September 12, 2009, 11:33:44 pm

Title: noob MAME/jamma questions.
Post by: duhh on September 12, 2009, 11:33:44 pm
Hey gang, let me start out by saying I have been browsing the forums for a couple of weeks and just joined. I have tried to read up on what I am asking about as much as possible, but still have some questions.

I spent a lot of times in an arcade as a kid and always dreamed of having one of those fantastic machines. It seems like lots of peeps are liquidating surplus entertainment these days, so I have picked up a few cabs. I plan on leaving most of cabs in their original state, but was looking at an already gutted cab from a gun game (crisis zone maybe?). It's basically the cab and a monitor for close to free.

I realize this is a bit ghetto, but for my first MAME project, I am wanting to only drop a bit of cash to get a technique down before I put together a "good" setup. As stated, i'm looking at an already wired crisis zone with a monitor. I was thinking that I can use a netbook or old pc do drive the thing, and I could get away only buying a jpac and perhaps an x-arcade stick. Yeah, I realize that looks like poop and is cheating, but for round 1, I am am OK with that. I can get away with all of this for like $250. When I built a real MAME setup I will go crazy and probably drop more money than I should on it.

jpac states that it converts 31khz to 15khz, but I can't imagine it's that simple. If so, why would they sell a dedicated card. Do i need to run soft15khz? Does that program even still work? All notes/releases I see seem really old.  Is there anything else I am missing here?

I currently have a 6x8 closet stuffed full of classic video games. I'd love to basement those things and only have to worry about having one cab instead of hooking up a different system all of the time.
Title: Re: noob MAME/jamma questions.
Post by: CheffoJeffo on September 13, 2009, 12:40:18 am
jpac states that it converts 31khz to 15khz, but I can't imagine it's that simple. If so, why would they sell a dedicated card. Do i need to run soft15khz? Does that program even still work? All notes/releases I see seem really old.  Is there anything else I am missing here?

No, it doesn't convert.

Quote
What does the J-PAC video circuitry do?

Besides amplifying the video level, the on-board video circuitry also synthesises composite sync from separate H-V sync from the VGA card. The J-PAC has a jumper which is set to the frequency that the monitor is designed for (most commonly 15Khz). The J-PAC will not pass the sync signal through unless it detects the signal is at the correct frequency for the monitor. Some older types of 15Khz monitor could be damaged if fed with a high sync rate. The J-PAC prevents this happening. If the sync rate is not in range, the monitor is still powered up and still has video passed to it but no damage can occur as the horizontal frequency cannot be driven too fast without any sync present. IMPORTANT: It is not a scan converter so you will have to configure the VGA card to send the correct sync rate for the monitor OR you can use our ArcadeVGA card which will drive a 15Khz monitor with no special configuration.

http://www.ultimarc.com/jpac1.php?to=5goto=3
Title: Re: noob MAME/jamma questions.
Post by: duhh on September 13, 2009, 12:48:18 am
So to beat a dead horse, soft15khz and jpac actually should do the trick?
Title: Re: noob MAME/jamma questions.
Post by: DynamiteSJ on September 13, 2009, 02:14:01 am
I would go for jpac or arcadevga... soft15k has too many issues and good luck if your using vista
Title: Re: noob MAME/jamma questions.
Post by: Beretta on September 13, 2009, 03:12:34 am
I would go for jpac or arcadevga... soft15k has too many issues and good luck if your using vista
the jpac wont actually convert the signal, all it does is block high freqz.. so think of it as a filter.. if it's 15khz it passes the signal though.. if it's higher then that it blocks it.
Title: Re: noob MAME/jamma questions.
Post by: mvsfan on September 13, 2009, 05:11:45 pm
Nes Powerpak = no Closet.