XEGS Suddenly Stops Working, Doesn't Seem To Be Dead Chips

[arcade124]

So, I recently picked up an XEGS from a user on here. It worked great...for the first couple of weeks. One day, when I was just playing it as normal, the scree suddenly went black. Seeing threads on here stating dead chips were likely at fault, I opened the console up and powered it on to see which chips got hot. Problem was, none did. I left it on for a couple of hours, and still none got hot, only a couple got slightly warm. So, no chips seem to be dead. Does anyone have any idea of what could be going on? I've attached an image of my power supply. Thanks for your assistance.

[SignGuy81]

I would have to see the schematic on the XEGS but I don't know if it has over voltage protection built in or not but I would be worried using the chinese power supply there and whether or not it has it built in. If not I would take a 5.6V zener and put across the power supply reverse bias inside the console to offer some protection. Of course you still have the original problem to solve first.

Edited April 10, 2018 by SignGuy81

[+Nezgar]

The modern power supply you picture could be a good suspect to rule out... Switching power supplies nowadays are made extremely cheap, and components can fail. I'd test the voltage output under load, as I've had a couple of these that undervolt on failure. Without opening the computer, you can put a voltmeter/multimeter across pin 7 and 8 on a joystick port.

 

A real Atari XL/XE brick powersupply with maintain a solid 5.0 volts. These little switching supplies I've seen drop to less than 4.5 under load - sitll working, but the color pot starts to shift at that point. If yours goes below that, the computer could fail to operate like you're seeing.

Edit: Adding joystick port pinout (At the Atari)

Edited April 10, 2018 by Nezgar

[arcade124]

So, if it's the power supply, does that mean I have to replace the motherboard?

 

If it's something to do with the power, I will mention one other thing. I'm guessing you guys aren't familiar with the company Dempa Micomsoft? Among other things, they made various unique controllers, such as one with two d-pads and the first-ever analog controller (assuming you count the 5200's as a joystick rather than a full-on controller). The type of controllers they were most famous for, though, was their line of high-end joysticks, most of them for SMS. I say this because they had battery-operated turbo functions. I've been using it on the XEGS since I got it. So, is there any possibility that the batteries are sending extra voltage that's messing something up?

[SignGuy81]

So, if it's the power supply, does that mean I have to replace the motherboard?

 

That would depend on how it may have failed. If it is like he said and the voltage is too low currently from it that is probably the problem still which is power supply or if it was like I said and allowed too much voltage a chip(s) into the console may have been damaged even if it was just temporary. He is right first thing you should check is the power supply voltage.

Edited April 10, 2018 by SignGuy81

[+Nezgar]

So, is there any possibility that the batteries are sending extra voltage that's messing something up?

I would think that's fairly unlikely... Most joysticks that do auto-fire functions draw their power from the computer however, and if that was the case that would be a litlte extra load for the power supply, which in this case could contribute to a failure if load was a factor. The label on your aftermarket power supply is rated for 2A which should be sufficient, as a stock Atari draws about 1A.

 

Undervolting usually doesn't cause damage to the chips with the same risk as overvolting, so crossing fingers there. But definitely start with checking the voltage of the power supply as I mentioned previously.

[arcade124]

I was able to get in contact with the guy who made the power supply, so he should know more about the voltage.

 

If I do end up needed to replace the motherboard, where would be the cheapest place to get one?

 

Also, just to clarify: it does still power up, the green light comes on and my TV goes from static to black.

[arcade124]

Just heard back from the guy who made the power supply, he said it's the correct voltage and he's made tons of them with no issues. Since Dempa's controllers are fairly rare, and only released in Japan while the system was never released in Japan, I doubt there's ever been any research into this. Any other ideas?

 

For reference, if anyone wants to take a look at the controller I've been using, it's the XE-1 Pro. It had some sequel controllers (e.g. XE-1 Pro FC), but this is just the original XE-1 Pro.

[SignGuy81]

Do you have a multimeter?

[arcade124]

Unfortunately, no.

[Zap!]

Just heard back from the guy who made the power supply, he said it's the correct voltage and he's made tons of them with no issues. Since Dempa's controllers are fairly rare, and only released in Japan while the system was never released in Japan, I doubt there's ever been any research into this. Any other ideas?

 

For reference, if anyone wants to take a look at the controller I've been using, it's the XE-1 Pro. It had some sequel controllers (e.g. XE-1 Pro FC), but this is just the original XE-1 Pro.

 

That doesn't mean it's definitely not the power supply. I'd find a way to test a working one on your Atari. Also, definitely invest in a multi-meter. They are essential in classic gaming repairs. Cheap too.

[arcade124]

If there's not a huge chance that it's the power supply, I'm not sure if I'd be willing to pay another twenty bucks for it, since I'll likely end up having to replace the expensive motherboard. But I might.

 

For the future, though, does anyone know where I can find the cheapest price on a motherboard?

[darwinmac]

On this page (http://www.best-electronics-ca.com/130xe.htm), you will find a populated XEGS motherboard for $65. I do not know your definition of expensive so this may be too much money.

 

Bob C

[+wongojack]

My .02 here. You have to rule out the power supply as the problem before you go to the expense and trouble of replacing the motherboard. What if the power supply IS the problem and it does damage to your new mobo?

 

The power supply is external and designed to be replaced for this very reason. It is relatively easy to get one that is known to work - go that route first.

[jaybird3rd]

I agree, rule out the power supply first. This OEM power supply from B&C ComputerVisions ...

 

eBay Auction -- Item Number: 140954042315

 

... is the one that originally came with the XEGS, and I've found it to be very solid and stable.

[Level42]

Woops.....not correct

Edited April 11, 2018 by Level42

[arcade124]

If it's possible that it's still an issue, I'll go ahead and get one.

 

Woops.....not correct

What's not correct?

[SignGuy81]

If it's possible that it's still an issue, I'll go ahead and get one.

 

What's not correct?

 

Pretty sure he just accidentally posted some wrong information and went back and edited it out after realizing. I do that all the time.

[arcade124]

Just got the power supply, it didn't fix it. Looks like I'll be replacing the motherboard. I'm not sure if I'll be using that controller on the XEGS again, I'll have to do some research to see if Micom's controllers were known for this, the extra voltage is fine for Japanese consoles but not US ones, or if it actually was the power supply.

 

For now, if anyone has a cheap spare motherboard (preferably under $45), let me know. I know it's a lot to ask, I just didn't want to pay $65 shipped for it when I already payed a hundred for the console barely a month ago. I have other consoles I'm looking to buy as well, I was just about to put out posts for them in the Wanted section, I'll be able to afford some of that anyway but I might just end up focusing on that for now. Still, if a new mb's affordable enough I'll be interested.