AS Gottlieb/ Q*Bert Power Supply Query

Phetishboy

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Has anyone who's installed one of these replacement switcher kits from AS had any video or audio trouble with it? I installed mine about an hour ago and everything comes up as it should, except I don't hear the "Hello I'm Turned On" greeting upon powering up the machine. I have Doyle's Multi-Q on this machine, and other than the frozen sounds the first 2 or 3 times it powers up (ANNOYING), it would finally always say the greeting after I'd power it up a 3rd or 4th time. Now, no greeting on power up at all.

Now onto the video. Other than some interference static/rods that I have always had on this monitor due to the filterboard or a ground or a combination of both, the video has always been crisp, the color clear and object and text edges were well defined. After installing the switcher, all red objects seem to be tearing, or at the very least have bleeding edges. Qbert looks to have horns the top of his head it is tearing so bad. I have not checked voltages, as I am not sure where Steve expects them to be at 5.05. At the switcher terminals? At the board? Doesn't really say. One cool thing is that I finally got my knocker working. I had a bad fuse. I had put one in when I bought it, but never metered it, cause it was new. Grabbed another new 1A SB and stuck it in there today, and low and behold, the knocker worked for the first time since I have owned the game.
 
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Well I got the greeting working upon power up now, did a little menu set-up as well. I still have the video tearing issues and monitor static, which sucks. Thanks for your help.
 
I'm in the process of building another Qbert. Have some sound issues still. I had a little issue with video after installing, bars like you stated, ensured the pcb ground was attached, no more issue.

Overall, very happy with the switcher and see no issues in the future with it. I better buy a lottery ticket. :D
 
The instructions tell you to tap into the monitor AC, which I did. Could that be causing an issue? As to the PCB being grounded, I'll check on that. The switcher is not yet field grounded, I'll do that first.
 
OK, got rid of the red tearing, apparently my red cut-off pot is pretty flaky. Cleaned it, turned it down a bit, and the tearing is gone. I still have the static rods though. Krack, where exactly did you ground your board to get rid of your static issue? I see no ground terminal or TP on the mainboard.
 
I'll snap a pic by tomorrow for you.

Where did you tie in the power for the AC?
Right before the molex on the monitor power wires. I tied in on the harness side, so the monitor can still be removed without cutting anything. It's a recapped 4900 but it has a singing flyback, so who knows when it will finally decide to blow.
 
That's where it is suggested to connect. I did the same thing.

Have you tried another monitor without issues?
 
Bringing up this thread so I can get out there to take a pic...
Hold your breath, I'll ask for blueboy in a few days...:eek:
 
It's a recapped 4900 but it has a singing flyback, so who knows when it will finally decide to blow.

An old trick to fixing the flyback whine - pull the chassis and remove the bracket from the top of the flyback. Take a wooden toothpick and jam it into the gap between the flyback core and the housing as firmly as you can. Break off the toothpick and put the bracket back on.

I've done this on a couple of 4900's, one of which was so loud that you really couldn't stand to have the game on for more than a minute or two. Quieted it right down.

-Ian
 
An old trick to fixing the flyback whine - pull the chassis and remove the bracket from the top of the flyback. Take a wooden toothpick and jam it into the gap between the flyback core and the housing as firmly as you can. Break off the toothpick and put the bracket back on.

I've done this on a couple of 4900's, one of which was so loud that you really couldn't stand to have the game on for more than a minute or two. Quieted it right down.

-Ian

Thanks Ian, I'll do that.
 
I just installed my switcher too. It seems to cause some of the audio to be distorted like when qbert talks or any of the other characters. The knocker is at half the "thunk" than it use to be. I also bought the sound cap kit but have not yet installed it. I hope that fixes the issues with the sound.
 
So is this one of the power supplys (like the classic Taito) that generally isn't worth repairing? Or are there other issues with it? Only one of this type I've had is Krull, and it still worked great.
 
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