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geekhack Community => Keyboards => Topic started by: lakiozoon on Sat, 05 September 2015, 02:37:11

Title: Problem with QFR - typing random letters, help needed.
Post by: lakiozoon on Sat, 05 September 2015, 02:37:11

I have almost the same problem as someone else described in:
https://www.reddit.com/r/techsupport/comments/3jb2ly/keyboard_types_by_itself/

Sometimes keyboard types for 15 seconds by itself, mostly containing +iop789+89+89+89 letters.
Sometimes after a single keypress a small sequence of letters is added. Scroll lock also pops up randomly.
So the issue i am having as identical as someone elses. That's a start.

I have not spilt anything on the keyboard, only thing i noticed is a severe weather change (we had a big rain after a long hot summer).

EDIT:
Found the old post on geekhack about the issue: https://geekhack.org/index.php?PHPSESSID=pkv8lucsvfhupn4moh6rd88877f31005&topic=35523.msg1437057#msg1437057

I loosened the screw in my QFR and the issue was solved.

Out of curiosity, I tried pressing on the case and every time i pressed the middle part of the bottom side of the case, keyboard spilt some letters in return (always the iop+789 ones), even with the loosened screw.

So, my best guess would be that something is pressing on the PCB, probably around the usb connector.

I would like to determine the cause of this issue.

Can any QFR owner do me a favor and try pressing on the case to check if it is a common occurrence. Just press firmly with your thumb on the QFR bottom label (near USB connector) without typing anything. You also need to be in some kind of text editor/browser to check for output letters.

Regards!

Title: Re: Problem with QFR - typing random letters, help needed.
Post by: rowdy on Tue, 08 September 2015, 06:11:55

There was an issue with some batches of QFR that the case was too tight, and even the official CM advice was to loosen the case a bit.

This has worked for nearly every case of misbehaving QFR that I have seen.

Title: Re: Problem with QFR - typing random letters, help needed.
Post by: lakiozoon on Tue, 08 September 2015, 11:04:34

Yeah, loosening the screw solved the problem, so i lost the motivation to dig deeper and determine the cause. Guess it's a minor design flaw of the keyboard.

Title: Re: Problem with QFR - typing random letters, help needed.
Post by: rowdy on Wed, 09 September 2015, 05:50:51

Quote from: lakiozoon on Tue, 08 September 2015, 11:04:34

Yeah, loosening the screw solved the problem, so i lost the motivation to dig deeper and determine the cause. Guess it's a minor design flaw of the keyboard.

Very likely.  At least CM did admit it at the time, and the fix is quite simple.