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geekhack Community => Keyboards => Topic started by: Dyaems on Thu, 06 October 2016, 09:29:12

Title: Newly Built Board Malfunctioned
Post by: Dyaems on Thu, 06 October 2016, 09:29:12
I need help guys. I just finished soldering switches in my ps2avrGB PCB. And while it was working properly, once I started hitting FN+any button (I tried shutting off the underglow using FN+another key) it started autopressing random/specific keys and now there is no way to revert it. While I am not really good at soldering, I think I did a decent job from it, and I did not touch any diodes or made the soldering iron stay on the pcb for too long.

Here are some pics:
(https://puu.sh/rzH4P/48f92e3583.jpg)
(https://puu.sh/rzH5E/a27176a015.jpg)
(http://puu.sh/rzH9L/2d5c631c2a.jpg)

And the random autopress from a key tester
(https://puu.sh/rzEGf/2ffeb7df66.png)
(https://puu.sh/rzFDo/5f30715a77.png)


Bad PCB? Any ideas or suggestions? I still have another PCB but I do not have any idea how to test FN+key becuase when I short the pcb with tweezer it always presses multiple keys.
Title: Re: Newly Built Board Malfunctioned
Post by: Tactile on Thu, 06 October 2016, 09:41:25
I am assuming that the PCB came with the controller & diodes already soldered. I am also assuming that you didn't slip with the soldering iron tip and hit a component you shouldn't have.

If the above is true, there is nothing you could have done to cause these symptoms. I'm not sure there is a hardware problem at all. Have you tried re-programming it with a very basic layout? Anyway, I think the problem is in the programming.
Title: Re: Newly Built Board Malfunctioned
Post by: Dyaems on Thu, 06 October 2016, 22:02:50
Yes I did not slip or even touched any diode at all while soldering the switches.

I had a backup file of the default layout and it still does the same thing when I tried loading it. I will try to fix the issue right now, just getting on more information.

edit: i also need to mention that i tested the PCB thrice (on different days) before soldering, but I have no way to test FN+key on bootmapper or key tester because it always presses multiple keys using a key tester.
Title: Re: Newly Built Board Malfunctioned
Post by: pomk on Fri, 07 October 2016, 01:27:40
The soldering on the chip looks sub par. Blobs of solder in front of the pins instead of a nice fillet. Does not necessarily explain what you are experiencing though. I'd trust wkl PCBs more. 
Title: Re: Newly Built Board Malfunctioned
Post by: Spopepro on Fri, 07 October 2016, 01:40:46
I've had to fix bad soldering on the controller on other WKL "replica" boards. A cold joint or a small bridge could do this. I'd make sure to try a known working usb cable first.
Title: Re: Newly Built Board Malfunctioned
Post by: Dyaems on Fri, 07 October 2016, 03:53:27
i think it was a bad pcb. i replaced it with another one and it works fine EXCEPT the F key is not registering, while I checked everything (by shorting the mounting holes on the pcb) before soldering the switches and the F key registers  :( any ideas?

i think ill just go back to topre haha
Title: Re: Newly Built Board Malfunctioned
Post by: pomk on Fri, 07 October 2016, 04:21:33
Or maybe don't expect too much from cheap chinese clones.

You would not expect 20$ topre clone to work well either.

You could try reflowing the affected key, its diode and the controller plus the controllers assorted components. In that order and check if it works after each step.
Title: Re: Newly Built Board Malfunctioned
Post by: potatobot on Fri, 07 October 2016, 04:35:05
give me your switches  ;)

sad day for cheap keyboard parts   :(
Title: Re: Newly Built Board Malfunctioned
Post by: Dyaems on Fri, 07 October 2016, 05:57:58
made a workaround bro with the second pcb by shorting it to another key haha

(http://i.imgur.com/fODe8M8.jpg)

the first pcb is totally dead  :(
Title: Re: Newly Built Board Malfunctioned
Post by: pomk on Fri, 07 October 2016, 06:20:45
The controller on the second board looks better, but still very uneven. It's likely some kid has soldered it by hand in a hurry, as PCBA would not leave the soldering job so uneven.
Title: Re: Newly Built Board Malfunctioned
Post by: Dyaems on Fri, 07 October 2016, 06:57:49
wish i know how to solder those small things-- im really terrible at it haha