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Thread: New Arcade Cabinet project Jamma?

  1. #21
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    That looks totally hinky, in particular the distortion of the raster and the areas bottom left/right corners.

    I see that again just after it tries to display game-box signal ;



    Those 2 blue/turquoise blotches bottom left/right corner and a bit at the top of screen. It has other problems apparent...ie; the horizontal sync is out/shifted & it didn't manage to obtain a vertical sync on the game-box signal, but, (and it's a big but), if that's some sort of display/CRT tube damage I can see, fixing the video driver board may be a lost cause....ie; it's still going to look like crap even with a good working video board.

    My gut feeling is those botches look like the shadow mask inside the CRT has moved or something..(or the yoke is very weirded out?)... the whole raster seems out of position somehow. Normally one doesn't consider that with CRT display, but with these arcade cabinets being subject to user abuse, and the possibility it may have fallen over/been knocked over/someone tried to punch the display's lights out etc etc, anything's possible (plus I've no idea how good the chinese are at making CRT displays =)...and of course someone may have futzed with things before you got it.... if there's anything to observe here, it would be my past experience as expounded beforehand -- when you see these cabinets being sold without game controller board, invariably it's because the VDU is cactus (which is why they're sold without the game board, because if it were fitted potential buyers would see they're up for a VDU repair/replacement =)

    However, you've already hinted at the fact you're half expecting to need shoehorn another display in there, correct? That'll get weird in it's own right very quickly, because typically the display aspect ratio is 4:3 or 5:4 and the world's moved on to widescreen 16:9/16:10 and thus things don't physically fit well. You can actually still buy these CRT display VDU chassis' out of China, but for mine that only makes sense from the perspective of authenticity ; modern tech displays look better =)

    This is me saying, personally speaking & having seen the ewetoob vid, my mind's jumped immediately from thoughts of repairing the VDU, to instead replacing it altogether...just because it looks like a CRT replacement job. I know forehand that I'll likely need to make up a bezel piece for the cabinet to finish things off and make it look pretty but that's easy enough done, and as for sourcing a display chassis, you can start with a search string of 'Arcade Game LED Monitor' to get an idea of what's out there. If you search about, you can find pearls like this ->

    BTW...was that CGA video or VGA?



  • #22
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    Ok so whilst a lot of that technical info went over my head the take away message for me is that it is likely that the monitor is stuffed

    I think that the monitor is cga but you have me wondering. The pandora box has 3 settings and i left it on the 16khz setting as it was what gave me a recognisable picture up front.

    The chassis has all the adjustments for the monitor annoying on the front, which means for me to adjust things id need to put my hands in across the live wires....something im not keen on. That said, based on the comments i feel like it might fix the v hold and the colours but there will still be problems.

    I could find someone to pay to repair but i think this will be uneconomical and defeating the purpose of a cheap build! This being the case im leaning towards removing the monitor and replacing it with a computer monitor (pandora box has both vga and hdmi output as well).
    I have a spare computer monitor so can hook that up outside the cab and see what it looks like.

    The question ill have is replacing the monitor means a, dismantling the cab quite a bit (dammit) but more importantly removing the current monitor. I know ill need to discharge the monitor cos it stores electricity and i dont want a zap for my efforts....how long will it store electricity? I really am not looking forward to a zap!

  • #23
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    I think that the monitor is cga but you have me wondering. The pandora box has 3 settings and i left it on the 16khz setting as it was what gave me a recognisable picture up front.
    Okay, you were using CGA (although 16kHz doesn't quite say it, should be 15.5somethingkHz really)...meh, jamma video isn't quite CGA anyhow =)


    I could find someone to pay to repair but i think this will be uneconomical and defeating the purpose of a cheap build!
    Very likely, and if the picture tube needed replacing most probably ; if the CRT looked okay, then maybe a repair would be economic... else, to stick with CRT, you're looking at ...ie;


    I have a spare computer monitor so can hook that up outside the cab and see what it looks like.
    Set the pandora box to VGA in this case


    I know ill need to discharge the monitor cos it stores electricity and i dont want a zap for my efforts....how long will it store electricity? I really am not looking forward to a zap!


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