‘A’ buttons not working on Atari Lynx 2

[ticman31]

Can anyone help with fixing my Atari Lynx 2 console. Initially I had ‘Insert Game’ error messages but after cleaning the contacts they all load fine bar 1. But now when playing and given game, they don’t respond to the A button being pressed. It’s the same when you flip the screen. Both B buttons work fine. Strange. Thanks 

[xhul]

Hello there, and welcome to the forums =]

 

The first thing to do would be to check if the ribbon cable (the narrowest of the 2) was inserted in its socket properly.
Simply disconnect and reconnect it, and be sure to insert it firmly before locking the socket.
After that, recheck all buttons.

 

If you don't see any improvement, it's very likely that the contacts on the cable have degraded too much.

Fortunately, there's an easy fix: https://atarigamer.com/pages/troubleshooting-lynx-model-2-buttons-and-d-pad#contacts

Note: Though you'll probably be tempted to remove all the degraded surface, 0.5mm is enough, from my personal experience.

Edited April 26, 2023 by xhul

[ticman31]

18 hours ago, xhul said:

Hello there, and welcome to the forums =]

 

The first thing to do would be to check if the ribbon cable (the narrowest of the 2) was inserted in its socket properly.
Simply disconnect and reconnect it, and be sure to insert it firmly before locking the socket.
After that, recheck all buttons.

 

If you don't see any improvement, it's very likely that the contacts on the cable have degraded too much.

Fortunately, there's an easy fix: https://atarigamer.com/pages/troubleshooting-lynx-model-2-buttons-and-d-pad#contacts

Note: Though you'll probably be tempted to remove all the degraded surface, 0.5mm is enough, from my personal experience.

Thank you very much for the info. I'm having trouble removing the ribbon, My understanding was it would pop/pull out easily from the clip-but I can't seem to locate it. I guess I'm just more about tearing it. Any info or links to a demonstration would be greatly appreciated.

[xhul]

You're supposed to gently open up the socket before pulling the cable out:

https://www.youtube.com/watch?v=W-oc-vpJlwM&t=740s

However, if you've never unplugged that cable before, then it's possible the issue actually lies somewhere else.
I mean, button(s) usually stop working right after you plugged the cable back in, because the action of plugging|unplugging the cable is what degrades the contacts.

Edited April 27, 2023 by xhul

[+Stephen Moss]

12 hours ago, xhul said:

You're supposed to gently open up the socket before pulling the cable out:

The video may show that but are you sure that is what you are supposed to do and not just someone taking the connector apart and potentially damaging it as a home made solution, rather than it being a designed method of releasing the tension on the cable?

I may be wrong but personally I would think the majority of the grip would be at the connection point itself to ensure good contact rather than the external cowl.

 

I have not extensively studied the data sheets of all FCC connectors but for those I have seen I did not notice any indication that was required to release the cable as with the exception of the ZIF versions I think they are generally designed with the intention of being insertion only. The ZIF versions which are designed more to allow easy insertion and removal and thus would would more likely be used where that was intended usually have a flap you lift that releases the tension on the flex for easy insertion/removal. 

 

On 4/26/2023 at 9:45 PM, ticman31 said:

Can anyone help with fixing my Atari Lynx 2 console. Initially I had ‘Insert Game’ error messages but after cleaning the contacts they all load fine bar 1. But now when playing and given game, they don’t respond to the A button being pressed. It’s the same when you flip the screen. Both B buttons work fine. Strange. Thanks 

Not sure why you would think that flipping the screen would produce different results.

Before messing with the ribbon cable have you tried measuring the voltage on pins 12 (B) and 13 (A) and see if...

a) The are the same when not pressed and

b) If they both change in the same way when pressed.

If you are not sure when end of the connector is pin 1 and which is pin 14, try pin for button B first to help you identify the correct end. Alternatively, I think TP6 may also be Button A and TP7 may be button B 

 

Do you know if it (particularly the front) has been taken apart before? If so it may just be that the alignment of the A buttons with the flex cable contacts was a little off on reassembly. 

[xhul]

1 hour ago, Stephen Moss said:

The video may show that but are you sure that is what you are supposed to do and not just someone taking the connector apart and potentially damaging it as a home made solution, rather than it being a designed method of releasing the tension on the cable?

I may be wrong but personally I would think the majority of the grip would be at the connection point itself to ensure good contact rather than the external cowl.

My assumption is that such system simply ensures the cable stays in the socket, even though the grip it creates isn't located where the contacts actually are.
If that's true, removing the cable without unclipping the thingy is probably a bad idea when it comes to the socket integrity, which is why i never personally tried.

1 hour ago, Stephen Moss said:

I have not extensively studied the data sheets of all FCC connectors but for those I have seen I did not notice any indication that was required to release the cable as with the exception of the ZIF versions I think they are generally designed with the intention of being insertion only. The ZIF versions which are designed more to allow easy insertion and removal and thus would would more likely be used where that was intended usually have a flap you lift that releases the tension on the flex for easy insertion/removal.

An insertion-only design sounds possible, though that wouldn't have been a very repair-friendly choice if that's the case.
One thing is for sure is that each time you insert|remove the cable, the contacts on it get significantly damaged, even if you unclip the thingy properly.
Maybe that's because the contacts on the cable are slightly too thick, or the contact grip too heavy, depending on how you look at it.

1 hour ago, Stephen Moss said:

Not sure why you would think that flipping the screen would produce different results.

I think he believed that the two A buttons were handled as fully distinct inputs, and that flipping the screen would disable one and enable the other.

Edited April 28, 2023 by xhul

[+Stephen Moss]

On 4/28/2023 at 9:34 AM, xhul said:

An insertion-only design sounds possible, though that wouldn't have been a very repair-friendly choice if that's the case.

True but if you consider that the production lifecycle of the Lynx would probably have been 5 years with a typical anticapated user lifespan of 10 years before moving on to something newer, rather than still using it 25 years later, then I doubt they expected to ever have to replace the flex circuit and that if they did determine it had failed then it does not matter if you break it during removal as you were replacing it anyway, so why pay more for a ZIF version as you would only really use then where you anticipate a lot of insertion and removal operations.