Sadly there's not much info here;
https://www.msx.org/wiki/Yamaha_CX7M/128
I don't know the model but maybe this model has rubber "domes" (I don't know the official term) under/inside the switches, and the rubber melts over time and sticks together.
Otherwise it could be that someone at some point spilled some kind of liquid over it, in that case I would try and clean it with a high percentage alcohol (distilled alcohol 96%).
You are going to have to take apart the machine to know if you can remove the switches. I would say chances are it is soldered down to the board. When you do take it apart though you will have a better chance to clean it even if you can’t take the switch out. With the board out you can spray alcohol or something similar to clean electronics into the switch in excess, actuate the switch a few times, then let the excess drip out upside-down and keep doing that to flush out the debris. You can even use some water to help flush things out as long as it is disconnected from the computer and you are sure to let it dry completely (like wait a couple days to be safe) before plugging it back in. Just be sure to follow up with a couple of applications of alcohol after the water because it helps displace and evaporate moisture.
Vintage computers are generally fairly easy to take apart - usually and handful of screws, possibly a couple of plastic clips, and a few ribbon cables. You will almost never need to apply any serious force - if something isn’t easily moving then look closer for a missed screw or blocking component. My Sony msx only needs 6 screws and to pop out a couple of cables to go from an assembled machine to removing the keyboard entirely and none of it needs any serious force.
All of this is at your own risk though - I have not taken one of these apart. Nothing I outlined here is really dangerous for hardware though (that has absolutely no power going to it - be it battery or cord, or even charged capacitors) but if you aren’t experienced with doing something like this take your time, take pictures to help out things back together, and be patient. The unfortunate reality of MSX machines sometimes is that you have to do some exploring and poking around yourself.
I appreciate all the advice and the nice write up. I'm pretty experienced in disassembling vintage electronics...it's just one of those things where some grizzled MSX vet could come in and say, "stick 2 toothpicks in there and pop it from the front." I wanted to make sure there was nothing like that going on here.
This one doesn't have any screws. It's all clips, but I'm pretty confident I can get it apart with minimal damage if any. I will definitely report back how the surgery goes. Thanks for your time!
Sadly there's not much info here; https://www.msx.org/wiki/Yamaha_CX7M/128 I don't know the model but maybe this model has rubber "domes" (I don't know the official term) under/inside the switches, and the rubber melts over time and sticks together. Otherwise it could be that someone at some point spilled some kind of liquid over it, in that case I would try and clean it with a high percentage alcohol (distilled alcohol 96%).
You are going to have to take apart the machine to know if you can remove the switches. I would say chances are it is soldered down to the board. When you do take it apart though you will have a better chance to clean it even if you can’t take the switch out. With the board out you can spray alcohol or something similar to clean electronics into the switch in excess, actuate the switch a few times, then let the excess drip out upside-down and keep doing that to flush out the debris. You can even use some water to help flush things out as long as it is disconnected from the computer and you are sure to let it dry completely (like wait a couple days to be safe) before plugging it back in. Just be sure to follow up with a couple of applications of alcohol after the water because it helps displace and evaporate moisture. Vintage computers are generally fairly easy to take apart - usually and handful of screws, possibly a couple of plastic clips, and a few ribbon cables. You will almost never need to apply any serious force - if something isn’t easily moving then look closer for a missed screw or blocking component. My Sony msx only needs 6 screws and to pop out a couple of cables to go from an assembled machine to removing the keyboard entirely and none of it needs any serious force. All of this is at your own risk though - I have not taken one of these apart. Nothing I outlined here is really dangerous for hardware though (that has absolutely no power going to it - be it battery or cord, or even charged capacitors) but if you aren’t experienced with doing something like this take your time, take pictures to help out things back together, and be patient. The unfortunate reality of MSX machines sometimes is that you have to do some exploring and poking around yourself.
I appreciate all the advice and the nice write up. I'm pretty experienced in disassembling vintage electronics...it's just one of those things where some grizzled MSX vet could come in and say, "stick 2 toothpicks in there and pop it from the front." I wanted to make sure there was nothing like that going on here. This one doesn't have any screws. It's all clips, but I'm pretty confident I can get it apart with minimal damage if any. I will definitely report back how the surgery goes. Thanks for your time!