Help hooking up GBS-8220 CGA to VGA convertor to replace a Ceronix 1492 monitor

knagl

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Help hooking up GBS-8220 CGA to VGA convertor to replace a Ceronix 1492 monitor

Greetings-

I am trying to replace a broken Ceronix 1492 13" monitor with a VGA LCD monitor.

I have purchased one of the CGA/EGA/YUV to VGA HD-Converter PCB (model GBS-8220) cards from Jammaboards.com - pictured here:

2441tvn.jpg


The documentation that comes with it is poor, to say the least. It is, however, supposed to be able to convert CGA to VGA.

As a simple test to make sure my board was working, I used the Y Pb Pr inputs on the card with video from my DVD player, and it did convert it nicely to my VGA monitor, so I know the thing is somewhat functional and I know that it's compatible with the VGA monitor I'm using.

I think I'm bumping into a sync issue. The game I'm working on outputs R, G, B, Ground, Horizontal Sync, Vertical Sync. The GBS-8220 does have an input section that, according to the printing on the board is: Ground, Ground, VS, HS, S, B, G, R. I have reason to suspect that the "S" here for this input is actually "shield" and not composite sync, and I'm not 100% sure what that means. Regardless...

I tried hooking up my RGB, Ground, and VS and HS and would only occasionally get a flickering of something on the monitor, usually in a single color (green, blue, or red mostly) for just a second or two here and there. The rest of the time I'd get a "No Signal" message generated from the GBS-8220 card. From the tiny bit I could see, however, it did in fact appear that it was trying to display the signal the game was sending out.

The documentation (again, limited) implies that for RGBHV input, it only accepts in the 31k range, which CGA is not. It does say that it accepts CGA at its 15k, but it seems to imply that for CGA it requires RGBS (Red, Green, Blue, Composite Sync) which one of the other inputs on the board ("P3" for those of you playing at home) is (which also has a ground pin, in addition to RGBS). As such, I'm guessing that I can't hook up my CGA output to the card as RGB H V.

So... my question is, has anyone used one of these boards to convert a CGA signal that used RGB H V into a VGA monitor, and if so, how do you have it connected? Do I need to somehow combine the sync signals and then try it on the P3 connector as composite sync?

Thanks in advance for any assistance you folks can provide.
 
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My guess: R G B is, of course Reg Green Blue. VS is Vertical Sync, HS is Horizontal Sync and S is Composite Sync.

Now, we're talking about a Chinese manufactured product. As such, it's inherently a piece of crap... so you're mileage may vary. But that surely sounds like the logical answer.
 
I too would assume that S implies composite sync. The seperate H and V sync should work as well - but if you've connected the S input to the shield ground, then it's no wonder it doesn't work :)

You can also try simply combining the H and V syncs together and hooking them to S - this works for some monitors.

-Ian
 
After you connect the wires be sure to press the "down/autoscan" button. This will make the card scan and detect the signal you're using. I have had one of these for a while to use with a med res game but It won't work. It might be the game but I haven't had a chance to try it with a different med res game yet. CGA worked fine right out the box though.
 
For the amount of money you spent on all that, you probably could have just gotten a new Ceronix chassis from Happ....
 
My guess: R G B is, of course Reg Green Blue. VS is Vertical Sync, HS is Horizontal Sync and S is Composite Sync.

Now, we're talking about a Chinese manufactured product. As such, it's inherently a piece of crap... so you're mileage may vary. But that surely sounds like the logical answer.

I thought it was logical, too -- as I originally posted:

I tried hooking up my RGB, Ground, and VS and HS and would only occasionally get a flickering of something on the monitor



I too would assume that S implies composite sync. The seperate H and V sync should work as well - but if you've connected the S input to the shield ground, then it's no wonder it doesn't work :)

I didn't connect anything to the "s" on the 8-pin connector as one piece of documentation I have indicates that it's "shield" -- not composite sync.

You can also try simply combining the H and V syncs together and hooking them to S - this works for some monitors.

When you say "combine" them -- are you saying simply twist the wires together?



After you connect the wires be sure to press the "down/autoscan" button. This will make the card scan and detect the signal you're using. I have had one of these for a while to use with a med res game but It won't work. It might be the game but I haven't had a chance to try it with a different med res game yet. CGA worked fine right out the box though.

I tried the down/autoscan button and then the card just froze -- no menu or anything after pressing that. Do you know, does it autoscan on a power-up of the card? I presume it does, as I know it tries to auto-detect where it is getting a signal from.

You said that CGA worked right out of the box for you -- I'd be very grateful if you could tell me which specific input connector you're using for CGA input to the board, and if the sync from your game source was composite or separate H & V (and if so, how you have it wired so that it's working). Thank you very much in advance.



For the amount of money you spent on all that, you probably could have just gotten a new Ceronix chassis from Happ....

Thanks for your help getting my game hooked up to a VGA monitor. For the record, the chassis is probably fine -- the monitor I got has physical damage to the side of it and the neck. You know where I can find a 13" tube with no burn on it for under $50? ...oh, and another one for my other game that I'm also looking to convert to VGA to get away from a burned tube?
 
For the record, the chassis is probably fine -- the monitor I got has physical damage to the side of it and the neck. You know where I can find a 13" tube with no burn on it for under $50? ...oh, and another one for my other game that I'm also looking to convert to VGA to get away from a burned tube?

I always just scavenge the picture tube from a junked TV set. Check the thrift stores and the curb on trash night. I've actually got a 13" set laying around with no use for it's tube - if you're located somewhere close by, you can have it.

-Ian
 
I tried the down/autoscan button and then the card just froze -- no menu or anything after pressing that. Do you know, does it autoscan on a power-up of the card? I presume it does, as I know it tries to auto-detect where it is getting a signal from.

You said that CGA worked right out of the box for you -- I'd be very grateful if you could tell me which specific input connector you're using for CGA input to the board, and if the sync from your game source was composite or separate H & V (and if so, how you have it wired so that it's working). Thank you very much in advance.
I used the one with the large pins. I think it's the P1 connector. My source uses a composite synch though. According to the manual the card is supposed to accept CGA and EGA on P1 and P3 so if you're using P3 with the connetor they included I don't know why it hasn't worked for you. As far as the Down/Autoscan button you're supposed to hold it down for 5 seconds and then release for it to autoscan.

As far as the connector I'm using it should accept both -negative, +postive synch and combined synch. If you're trying to connect your game to the large pin connector and your game uses both negative and positive synch you can try twisting the synch wires together and connecting them to the synch pin.
 
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I always just scavenge the picture tube from a junked TV set. Check the thrift stores and the curb on trash night. I've actually got a 13" set laying around with no use for it's tube - if you're located somewhere close by, you can have it.

I appreciate the offer (really), but I'm rather hell-bent on getting this thing converted to a LCD monitor.
 
As far as the Down/Autoscan button you're supposed to hold it down for 5 seconds and then release for it to autoscan.
I thought that was to reset the card? I'll have to try that and see if it works. I'm going to try the input with the large pins, too, I just need to figure out how to combine my H and V sync to composite so that the card will like it.

As far as the connector I'm using it should accept both -negative, +postive synch and combined synch. If you're trying to connect your game to the large pin connector and your game uses both negative and positive synch you can try twisting the synch wires together and connecting them to the synch pin.

I have wires from the game indicated as "H Sync" and "V Sync" -- are those "negative" and "positive" sync, or is that something else? I'm new to the world of RGB and sync.
 
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I have wires from the game indicated as "H Sync" and "V Sync" -- are those "negative" and "positive" sync, or is that something else? I'm new to the world of RGB and sync.

Nope - those are the two separate sync signals, likely both negative. Most newer games output only negative sync. Some older games, like Defender, output positive sync signals - that is, positive horizontal and positive vertical sync. They need to be either connected to a monitor's positive sync inputs, or inverted with an inverter chip and fed to negative inputs.

I would doubt that your previous monitor even took positive sync at all - most newer monitors only take negative sync.

Technically, there is a better way to make composite sync from separate syncs... but you can just twist the wires together and try it that way.

-Ian
 
Thanks for your help getting my game hooked up to a VGA monitor. For the record, the chassis is probably fine -- the monitor I got has physical damage to the side of it and the neck. You know where I can find a 13" tube with no burn on it for under $50? ...oh, and another one for my other game that I'm also looking to convert to VGA to get away from a burned tube?

I always just scavenge the picture tube from a junked TV set. Check the thrift stores and the curb on trash night. I've actually got a 13" set laying around with no use for it's tube - if you're located somewhere close by, you can have it.

-Ian

That is correct. 13" TV's can be had for about $12.

But if it's help you want, I can tell you that I tried repairing, then replacing, a 19" version of the very same Ceronix chassis, and couldn't get it to display via VGA. I had a lot of fun adapting a standard VGA connector to the VGA connector used on the Ceronix, and could not get it to work properly. I figured out later that the game pcb (this was in a video poker, btw) wasn't outputting the video signal at the proper voltage for the monitor to display.

And I've also had a lot of problems with those CGA-to-VGA converters not always converting every video input. I've had some boards work just fine, and others not work at all.
 
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I can tell you that I tried repairing, then replacing, a 19" version of the very same Ceronix chassis, and couldn't get it to display via VGA. I had a lot of fun adapting a standard VGA connector to the VGA connector used on the Ceronix, and could not get it to work properly. I figured out later that the game pcb (this was in a video poker, btw) wasn't outputting the video signal at the proper voltage for the monitor to display.

And I've also had a lot of problems with those CGA-to-VGA converters not always converting every video input. I've had some boards work just fine, and others not work at all.

Very helpful, thank you for your reply. I'm actually working on a video poker machine myself -- an IGT Players Edge Plus, to be specific. Do you happen to know if that was the type you were working on? Also, were you using one of these cards (GBS-8220) when you attempted to do the conversion, or something else? Is there a way to determine what voltage is being outputted by the machine, and what voltage is needed? Thank you in advance.

Also, apologies for being a little snarky earlier. I realize that I'm new here and that it isn't the most endearing quality of a new poster.
 
Well, I don't know about your slot version, but my version needed 230vac monitor power to work. I had a fun time figuring out how to generate 230 volts on my test bench, as the back of the monitor had a plug that seated into a socket inside the video poker and I couldn't access the back of the monitor while it was installed. I finally figured out how to do it using an Atari power brick:

http://forums.arcade-museum.com/showpost.php?p=753176&postcount=55

I found that you couldn't get an image on the monitor if you only supplied 120vac to it. The monitor would only give a very faint "chirping" noise. If you're trying to wire in an LCD monitor into your video poker, you should verify that it's 120 and not 230. if it's 230, that might have something to do with why you can't get a picture - you might have fried the monitor (or blown the internal fuse).

Now, I was attempting to repair the Ceronix, not replace it with something else, so I never did what you are attempting. I did the opposite - trying to get a VGA signal to display on the Ceronix monitor. As this was a customer job, they decided to go with the cheaper route and just replace the chassis with a new one from Happ for about $100. The version I had was the VGA version of this chassis, so I was inputing voltage of 0.7vdc per color. Your CGA version should have about 3vdc (according to the manual) inputting for the color. That's what should be input to your converter.

The converter I had was slightly older and came with no paperwork. I found that messing with the dipswitches would give me a good pic for one CGA board, but another CGA board wouldn't work, and I'd have to mess with the dip switches again to find a setting that worked. Sometimes I couldn't find a setting that worked. I also discovered that it wouldn't display a picture for one game on an LCD computer monitor I wanted to use, but it WOULD display a picture for the same game pcb on a CRT computer monitor I had. I eventually found it to be too much trouble to use on the test bench, and just went back to a standard arcade monitor.

And the video poker had been customized with sport graphics, so I have no idea what model it was before that...
 
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I'd like to know what LCD you are putting in this video poker ?
Is it a kit ?

I'm in the process of putting a 15" LCD in one, no kit....just me trying to finaggle it.
So I figured I'd ask out of curiosity.
 
The converter I had was slightly older and came with no paperwork. I found that messing with the dipswitches would give me a good pic for one CGA board, but another CGA board wouldn't work, and I'd have to mess with the dip switches again to find a setting that worked.

I've seen pictures of that board with the dipswitches, but do not have that one. One "advantage" of that older board is that, from what I've read, one of the dipswitches is used to tell the board whether or not you're using composite or separate sync.

My machine is spitting out 110 to the Ceronix 1492 monitor. I haven't even gotten to the point of trying to actually put the LCD into the machine yet -- I'm more-or-less doing this on the bench, with my LCD monitor plugged into a normal outlet, and the GBS-8220 card being powered by a separate power supply. As I mentioned, I did test this first with a DVD player and so far so good with that. Additionally, I'm actually getting the message "No Signal" displaying on the screen, which is video generated by the GBS-8220.

I'm beginning to more and more think that this is a sync issue -- I just haven't had the opportunity to tinker with it more and won't for about a week and a half as I go on vacation this Friday.


I'd like to know what LCD you are putting in this video poker ?
Is it a kit ?

I'm in the process of putting a 15" LCD in one, no kit....just me trying to finaggle it.
So I figured I'd ask out of curiosity.

Hi Kevin. I'm a Kevin too, and I'm also trying to finaggle it. :) Ceronix does sell a plug-and-play LCD kit, but it's roughly $460 which, as a home user, is a little spendy. Are you trying to convert a PE+ as well? Do you have a CGA to VGA conversion card like the one I bought, or a different one, or anything? I'm just using a cheap LCD VGA monitor that I had laying around.
 
IAs far as the Down/Autoscan button you're supposed to hold it down for 5 seconds and then release for it to autoscanQUOTE]

Hey - im trying to hook up somting very similar. When you say hold the autoscan is that on the new card you are installing or is this on the origiaonl boards? I ordered one hooked it up and it didnt work so i emailed the company for trouble shooting advice and they said "it no work, not ok we send you new". That was somewhat helpfull but i dont want to try the new one if i am not sure i am hooking up the old one correctly.
 
Hi Kevin. I'm a Kevin too, and I'm also trying to finaggle it. :) Ceronix does sell a plug-and-play LCD kit, but it's roughly $460 which, as a home user, is a little spendy. Are you trying to convert a PE+ as well? Do you have a CGA to VGA conversion card like the one I bought, or a different one, or anything? I'm just using a cheap LCD VGA monitor that I had laying around.

I've got a pretty dead and rough Fortune 1 machine I'm converting to run PC slot games with a 15" touchscreen. So I won't be having to do any CGA to VGA conversions or anything for this one. I was mostly curious about how you were mounting your LCD as I've had to make my own brackets, etc. I'm trying not to modify any of the original cabinetry as I do plan on getting the original game to run one of these days just for kicks. It's a Draw Poker - not one I really need as a dedicated machine, I have plenty of "card games" for people to play.
I'd like to see a pic of your monitor installation once you get it squared away.
The weather here has kept me from digging mine back out and getting it finished.

I haven't messed with one of those converters like you are trying, but all I can add is that I have heard mixed reviews as some have already mentioned. One guy will say it worked like a charm, another will never get it to work with what they are using.
 
slot

i suspect igt and other slot makers have thrown a wrench into this idea
as, they put out odd voltages for rgb,sync, and odd for yolk to in an effort to make none of thier monitors compatible with other slot makers monitors or generic replacements.
youll have to get an igt approved lcd and kit i think
 
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