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Author Topic: Testing / checking monitor hookups? I need some more help.  (Read 2075 times)
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Otaku
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« on: October 12, 2014, 01:55:13 pm »

Well, back to the Continental Circuit again. The converter board (to VGA) arrived, I asked for a different cable but I'm not sure if they gave me the right one or not. Seems to be fine. Well, some guy who had it before me (the machine) spliced the monitor hookups into some long wire going into a molex, I first tried inserting things into the molex and using them on the RGBS pins on the board, then the cable that attaches to the other port. Nothing. Ripped out the slaughtered splicing, put them together how they were on those cables to the cable that came with the board, and still nothing onto the new connector. Is there any way to test that these are outputting what they are supposed to be? The board is displaying "NO SIGNAL" across all hook-ups, so the board is fine with the monitor but nothing happens with the machine. How it was wired: (The "colors" also used 'correctly' colored electrical tape around the points it was wired together, also appeared to be slightly soldered although it doesn't matter much now, disconnected)

Arcade Red -> Molex Red -> Board Red (R)
Arcade Green -> Molex Green -> Board Green (G)
Arcade White -> Molex Blue -> Board Blue (B)
Arcade Black -> Molex Yellow AND White -> Board Light Gray (a.k.a. Molex White) and Board Yellow (a.k.a. Molex Yellow) (Sync?)
Arcade Ground (Brown?) -> Molex Black -> Board Black (Ground)

Anything I can do with these using a multi-meter or something?
« Last Edit: October 12, 2014, 01:57:40 pm by Otaku » Logged
iankellogg
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« Reply #1 on: October 12, 2014, 10:32:44 pm »

the only thing you can do with a multi meter is put it on AC and put black led on video ground and try to probe the other lines, should be an AC signal somewhere between .5 and 2V

Sadly without the proper equipment, such as a known working monitor or an oscilloscope there isn't too much you can do.


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VertexGuy
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« Reply #2 on: October 13, 2014, 06:49:02 am »

some of those vga adaptors come with V and H synch wires.
you might only need the V or both at same time.
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Otaku
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« Reply #3 on: October 17, 2014, 09:28:50 pm »

Very quick edit: I'm also connecting directly via the RGBS area now (I found a decent way to connect the wires without molex, works great it seems Tongue), the board seems to know that as that is the mode it is in when it starts up, but it still gives "No Signal". The game has no seperate H and V sync wires, just one sync wire. Smiley

Picture 1 for thread: https://scontent-b-lga.xx.fbcdn.net/hphotos-xpf1/v/t1.0-9/10425845_1483685525246239_3700053390491421132_n.jpg?oh=3f21ad88d60aff7703efd984ca122686&oe=54BD4D17
Picture 2 for thread: https://fbcdn-sphotos-f-a.akamaihd.net/hphotos-ak-xfa1/v/t1.0-9/1505012_1483685505246241_3187464009410708806_n.jpg?oh=713c3cb90ce422dd35a4687f2fa6f91b&oe=54B3B453&__gda__=1425156709_88acb8a662e0f1ddfebf6ed62610abe6

I checked the voltages doing what Ian said, it turned up being Red & Green quite low 0.1v - 0.5v, Blue kind of behaved the same but I think it jumped to 1.8v at some point, but maybe it was just a bad connection or something. Sync gives like 0.1v. There's some unused wires at the back of the machine (guessing they're power for the old monitor(s)), I stuck the multimeter ends in that molex connector without changing it off of AC, turned on the machine, yet again, and it measured 130v~. Not sure how accurate that is, I'm American so I think all of the outlets in this house are 110v - 120v. Weird. Anyways, would grounding that green wire do anything? I don't know if it's like a precautionary ground for the original monitor power or whatever. There's also a spot that seems to be to ground something on one of the boards, and a red LCD light that doesn't light up. The connector on the end of the green wire is a circle connector, forgot what they are called.

The game works based on the sounds and I can even get into the sound test menu by setting a dipswitch and pressing a button, learned that from the 'MAME rom' of it. Everything seems to work, but no picture. Sad Please help if you can! Thanks!
« Last Edit: October 17, 2014, 09:34:48 pm by Otaku » Logged
iankellogg
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« Reply #4 on: October 18, 2014, 01:10:12 pm »

Here is what i am thinking. Something is probably going on with your sync signal. One of the worst things about those converter boards is their inability to handle strange sync signals. If you could find a CRT monitor to try then you might be able to see something but possibly not in sync. As far as fixing it, not sure how i can help unless you know your way around a logic probe.
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Otaku
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« Reply #5 on: October 18, 2014, 01:28:28 pm »

I guess I could try to took it up to my other machine's monitor (although I'd rather have one broken machine then two, seems easy enough, haha, with the molexs) to see what happens. Yeah, I've been reading up on the board some more. Is this something possible to fix with other little pieces or is this just something that will never work for this machine? I don't think I'll bother returning the board, I could always use it for something else in the future.
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Otaku
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« Reply #6 on: October 18, 2014, 01:53:31 pm »

Ehh, I just pushed it back up against the wall and closed it up, I guess I'll with it another day. Tongue Maybe I'll be able to find a cheap monitor some-place. Smiley
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