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stj

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thats not the voltage, your meter cant show it.
you need a scope - the pulses are 5v but your seeing an averaged value based on the percentage of time they are high.
if you look at the schematic, all 3 sync signals come directly from 5v logic chips
 

Dwatters

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well in that case i think ill have to call it quits on this one for now. i put 1k in series on both h and v sync and it was still just flashing the screen out of sync most of the time and when it would stay on for a couple seconds out of sync you could see that the video was actually playing tho. i dont think i can do any more until i can get it connected to a known working monitor i guess
 

stj

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i have a link to a good 5v to 3v convertor circuit - i'll try to find it
 

Dwatters

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OK worth a shot. Also the second led I asked about, it doesn't do anything at all. I haven't probbex it yet tho to see if it's just a bad led
 

stj

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found it
 

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Dwatters

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I finally got around to putting in a level converter. It's kinda different but still not work. I'll get a video uploaded in a few. When I use hsync and vsync lines I get a scrolling image that switches from that to no signal. If I use either of those lines or the jamma sync line to the sync pin I get the static image again
 

Dwatters

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I finally got around to putting in a level converter. It's kinda different but still not work. I'll get a video uploaded in a few. When I use hsync and vsync lines I get a scrolling image that switches from that to no signal. If I use either of those lines or the jamma sync line to the sync pin I get the static image again
View: https://youtu.be/5X7N2b7Z-DY
 

Hydreigon

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Williams and Midway are known for abusing CRTC related parameters to change the refresh rates on the fly. It's difficult to get these games running on anything but a CRT.

Edit: Maybe I am incorrect but it's been a while since I seen a GBS related thread like this.

Edit 2: I am going to have to give someone credit for this one: https://forums.arcade-museum.com/threads/midway-terminator-2-monitor-help.496155/
Terminator 2's vertical refresh rate is 53 Hz, not 60 Hz. go look around to see how people rigged up LCDs on Mortal Kombat or NBA Jam, same procedure.

I don't do anything with LCD conversions. for all the trouble you could've just sent the monitor chassis to me to fix, assuming it's a K7000. and probably be money ahead.
 
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dennisfxm

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If it helps, to get the vanilla GBS (I never not GBS Control to work) to work with my WWF Wrestlemania, in the set up, I set H Position 32 and V Position 28. I also have to remove any resistor. It looks like the first reply mentioned the V position, but I remember having to fiddle with the H position as well.

Also, in my notes, H Size is 52, V size is 52, clamp st is 90 and clamp sp is 95. I don't remember messing with these values though.

I know Wrestlemania is a different board, but it's still midway, so it might be similar. I'm powering my GBS with 5v from my arcade PSU and connecting the to the 5 pin input.
 

Dwatters

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Hmm OK well then I guess this really isn't worth the headache lol. I do have an imperial monitor with a jc-tron board that I need to figure out. Did a full recap and transistor but haven't been able to get it to power on yet
 

jassin000

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GBS is trash, even with the GBS control work its better than stock sure but nothing next to a real/legit solution like the OSSC or Retro Tink 5x.
Midway boards are known for wacky resolutions and scan rates... Something like the GBS is going to choke on it.

OSSC works the best for Midway out of everything I've tested.
Allows you to set the active area to greater than 240 lines tall, which is key for MK games/won't cut off the life bars or floors.
 

Dwatters

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Yeah I see that now lol. I also have a Sega masters shooter that also has no monitor so I may need to see if that boots and try it on there. I do need work out this monitor also. That or I will just pull this high impact board out and swap in something else or even one of those 60 in 1s lol
 

Hydreigon

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GBS is trash, even with the GBS control work its better than stock sure but nothing next to a real/legit solution like the OSSC or Retro Tink 5x.
Midway boards are known for wacky resolutions and scan rates... Something like the GBS is going to choke on it.

OSSC works the best for Midway out of everything I've tested.
Allows you to set the active area to greater than 240 lines tall, which is key for MK games/won't cut off the life bars or floors.
Their games with network play are known for any slave machine adjusting refresh rates on the fly to keep up with the master machine. It's a problem for some LCD monitors and converters.

I had no issues with linking two Motocross Go pcbs, running on Namco System 23, with the craptacular GBS HDMI converters.
 
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