Keyboard Multimeter Continuity Issue.

[scubaskot]

Hey, I got an old mechanical keyboard that Im planing on using it, but it has been acting weird. Most of the keys are working fine, but some of them are messed up. Few of them need to be pressed hard in order to register the character or when they are slightly pressed the keyboard registers double or multiple clicks or in some cases it doesnt register anything, EXCEPT when Im testing the individual key with a multimeter for continuity and thats when finally the key starts working again.

 

Now I am asking for your sugestions what I could possibly do to fix it.

 

Thank you!

[geo3]

What kind of keyboard? What switches?

[scubaskot]

It is an old Razer blackwidow 2014 that I hadnt been using it for a while. Now, i must admit that it was stored for a few years in a humid room. Also tried their software Synapse but no luck.

 

Some guy recomended me to clean it with contact cleaner or make an RC circuit to solve the multi click issue, but I havent a single clue how to do that.

[geo3]

First short the switch pins on the back of the PCB with a metal tweezers  to check if it's the PCB or the switch. If the issue still happens then the problem is the PCB. If it's stable making contact using the tweezers then the problem is the switch. I'd recommend replacing them. You will need to buy a pack of switches on line and also do some soldering.   It could also be that the solder joint broke, in which case you would just need to re flow the solder in the joint. You can tell by visually inspecting the solder on the switches that are acting up for small cracks. 

[scubaskot]

I used a metal tweezer as you recommended and it makes contact. As for now I will get a can of contact cleaner and see if that would work, since I dont see any small cracks in the solder joint on any of the problem keys. If this ends up not working I will try to re flow before replacing the switches. I do have a heat gun, but i have no idea how long I should heat the back of the PCB.

 

Also, is aliexpress the cheapest way to buy mechanical switches?

[geo3]

1 hour ago, scubaskot said:

I used a metal tweezer as you recommended and it makes contact. As for now I will get a can of contact cleaner and see if that would work, since I dont see any small cracks in the solder joint on any of the problem keys. If this ends up not working I will try to re flow before replacing the switches. I do have a heat gun, but i have no idea how long I should heat the back of the PCB.

 

Also, is aliexpress the cheapest way to buy mechanical switches?

I would not recommend using a heat gun. It heats too wide an area and you will likely melt a switch or desolderer a near by resistor or diode. A soldering iron is really recommended. 

 

I would get switches from either novelkeys.xyz, kbdfans.com or mechanicalkeyboards.com.