Up mysteriously quit working

[+atari2600land]

I got the AC adapter to work, but now the up button won't. Is there a way I can fix this?

[xhul]

Hello there =]

1) Did the UP button actually use to work in the past? or is it a recently acquired machine?
2) Did you recently unplug|re-plug the smaller ribbon from its socket?

[+atari2600land]

1.) I got the Lynx in the mail a few days ago. Everything was working fine. Then I didn't play it for a couple of days and I got an official A/C adapter, box and all, in the mail. I plugged it in and eventually got it working, but the up button had stopped.

2.) No. I don't know how.

[xhul]

Thank you.

 

So if i understood well, you never opened the lynx, and had a chance to test it using batteries before receiving the adapter, at which point the UP button was working.

That may sound dumb, but did you try to switch back to batteries to see if the button works again?

 

About the adapter itself, "eventually got it working" sounds strange to me, does that mean it didn't work right away? If so, what did you do to make it work?

Edited June 15, 2023 by xhul

[+atari2600land]

Yes, I tried just batteries without the adapter and UP still wouldn't work.

I had to discover the adapter only worked if a game was plugged in. It works most of the time, though. Worst case scenario is I'd have to unplug it and plug it back in.

[xhul]

Yes, on unmodified machines, a cartridge has to be inserted to get a power on.

 

Regarding the diagnostic, i guess we're gonna need the help of some other users here.

As far as i'm concerned, the big question is if the issue is related to the first use of the adapter or not.

Right now, i could see one scenario where a component (mechanical or electrical) simply reached its end of life, without the adapter being directly involved.

An other possibility is that the first use of the adapter somehow fried something (not impossible considering the 9>5V conversion is one of the lynx's weakness).

Either ways it's weird that only the up button is affected.

A bad contact on the ribbon side is usually what causes such things, and that can happen easily when the lynx is disassembled.

However, i don't see it happening without having opened the lynx at all, assuming it didn't suffer any significant shock between when the button worked and when it stopped working.

[+-^CrossBow^-]

As it was working before but now it isn't I had this happen on a Lynx II only it was on the left button. The issue was that the actual rubber for that button had started to break along the seam of the molding. What was happening was the button wasn't springing back up and was essentially always making contact with the direction pad as a result of this. I fixed it by replacing the rubber membrane for the dpad from another parts donor Lynx II console.

 

@Igor at K-Retro has replacements you can buy. Again, I'm not sure this is the exact issue you have going on, but as you haven't opened it up, it is the only thing I can think off having seen it at least once before.

 

https://k-retro.com/atari-lynx-replacement-parts/71-key-rubber-pads-for-atari-lynx-2.html

 

 

 

[+atari2600land]

How do I open up a Lynx II?!

[xhul]

https://atarigamer.com/pages/lynx-2-disassembly-steps-and-screw-size-chart

some additional pictures here:

https://atarigamer.com/articles/atari-lynx-repair---part-1---introduction-and-case-disassembly

also:

https://forums.atariage.com/topic/211456-lynx-ii-disassembly-guide/

 

Edited June 15, 2023 by xhul

[Igor]

While you have it open, you absolutely must replace the MOSFET/zener as that is part of a power circuit that can fail and kill your Lynx's CPU, and while you're at it, get a BennVenn IPS kit from our shop (K-Retro) and replace the original screen, there's no soldering required.

[+-^CrossBow^-]

17 hours ago, atari2600land said:

How do I open up a Lynx II?!

You have to remove the rubber grip pas along the back side of the Lynx II first. You will find the 4 main screws that hold the two case shells together.

There is also a smaller phillips located in the center of the battery holder section that you will also have to remove before you can start to access and get things removed.

 

Then you will also have to carefully remove the LCD interface ribbon cable and front control ribbon cables. Be sure to remove the bales on the sockets for those ribbon cables before you try an pull them loose.

 

From there the main board will essentially come out allowing access to the screws that hold the LCD in place and the frame for the buttons and membranes. 

 

 

[danny_galaga]

Sometimes things happen at the same time. Could be the UP contact needs a clean. If you do that, clean all contacts while you're in there.