ESC and F keys not working after soldering

[Ronimeister]

Hi everyone,

Just finished my first switch lubing on Varmilo VA87M Summit R2 and everything seems to work fine except for ESC and some of F keys (F1 - F8),  F9-12 work just fine. At the same time diodes on these keys work fine, but the keys themself are not registered when pressing.
So, could you please help me understand if I did something wrong while soldering and how should I fix it? I think the problem may lie with ESC or F8 key, but I might be wrong.
Also, if it will not be possible to fix it, how could I bind 'ESC' key functionality to another key?

Thanks and have a great day!

[Signature]

I'd say, test the faulty switches with a multimeter. They could also have bent pins (although it doesn't look like it from the pictures).

[Ronimeister]

I'd say, test the faulty switches with a multimeter. They could also have bent pins (although it doesn't look like it from the pictures).

I don't think that the problem lies with switches, because when I started to reassebmle the keyboard after soldering I put first switch into 'Esc' placeholder and it didn't work. Then I tried to use another switch - still no response after a click. Then i tried to use these switches in another places and they worked like a charm

[fortissim2]

Seems like a problem with the PCB.
An easy fix would be to just get a new keeb, idk what else you can do

[Ronimeister]

Seems like a problem with the PCB.
An easy fix would be to just get a new keeb, idk what else you can do

Do you know if I can just get new PCB? Maybe there is smth similar to this Varmilo PCB on the market?

[fortissim2]

Do you know if I can just get new PCB? Maybe there is smth similar to this Varmilo PCB on the market?

Not sure, but I don't think anyone would sell PCBs for prebuilt keyboards.

[suicidal_orange]

You've almost certainly damaged a pad or two, Varmilo's boards are usually not made by crazy people as many commercial boards are so if you plug it in and touch a wire between the blue and red dots I suspect it will type F8.  If it does solder the wire between blue and orange pins and all the keys will probably work again.



If that doesn't work (the diodes are in pairs which looks a little strange...) post what happens and I'll look harder - we'll fix this, definitely don't buy a new board!

[Merranza]

This keyboard lost all its respect

[Ronimeister]

You've almost certainly damaged a pad or two, Varmilo's boards are usually not made by crazy people as many commercial boards are so if you plug it in and touch a wire between the blue and red dots I suspect it will type F8.  If it does solder the wire between blue and orange pins and all the keys will probably work again.

(Attachment Link)

If that doesn't work (the diodes are in pairs which looks a little strange...) post what happens and I'll look harder - we'll fix this, definitely don't buy a new board!

Good day sir, I will try it this evening and will let you know the result. Thanks for the tip!

[Ronimeister]

If that doesn't work (the diodes are in pairs which looks a little strange...) post what happens and I'll look harder - we'll fix this, definitely don't buy a new board!

Also, if it's possible, could you please suggest me a decent tutorial on how to do that correctly?

[suicidal_orange]

A tutorial on how keyboards work?

It's pretty simple really - one pin of each switch is attached to a diode (you can see these connections on the back of your board) then the other end of the diodes are connected into groups which all connect to the same pin on the controller chip.  You can see the diodes connecting sort of vertically on your board so these groups would be called "columns".  The other switch pins are directly connected in groups and as the diodes are vertical these would be called "rows".  To use less pins when designing the PCB you can use U shaped "columns" which are made up of two physical columns with two "rows" connecting to every other switch in the physical row, or if you don't want people to fix your boards you can connect switches seemingly at random.  Thankfully yours is not in the last group.

Once you've worked out what should be connected to what you just solder a jumper wire to replace the damaged connection.  Any wire will do, it can't be thinner than the traces on the PCB and keyboards aren't sensitive to interference.  If the wire is not insulated just bend it so it doesn't touch anywhere it shouldn't.

If you search for "keyboard switch matrix" you'll find plenty of info