'f' key doesn't work, except when keyboard is turned on, when it repeats infinitely
 

The 'f' key no longer works. However, when I turn the keyboard on (it's a wireless with a power switch.), it sends an infinite number of 'f's until I press a key, at which point that stops and it works normally, except no 'f's. I assume it's just dirty and I have to take it apart. (I've already flooded it with contact cleaner and canned air and held it upside down with the vacuum cleaner on the 'f' key.) I'm curious about how to make sense of this behavio(u)r. Logitech K360.

I suspect the switches are sealed, so contact cleaner won’t do anything. If it’s a contact problem, best replace the keyboard. $30!
That’s the keyboard I use. I really like it. I “clean” it by powering it off and gently tapping it upside down.

But seriously, $30...get a new one.

If scasey's guess is wrong and the keyboard is not sealed, try prying off the key cap. I've occasionally had a bit of debris get lodged beneath a key on my laptop too large to blow or shake out (like a tiny scrap of paper, for example) and have removed it in that way.

Good point, frankbell.
Another thought: if that only happens when you first turn it on, stop turning it off. I never turn mine off. Batteries last more than a year.

I agree since I also leave mine on almost 100% of the time. The reality with that suggestion is it doesn't fix his problem with that one key not working and simply ignores it. It also does not address other possible damage down the road as a result. The suggestions by @frankbell are possible solutions and do not leave the one key stuck and not functional.
I checked on line and that keyboard is shown at Staples and Best Buy for ~$20, or $30 at logitech.

Oh. I missed that the f stops working after another key is pressed.
Yup. Replace it.

I bought it for $20 at the Mart of Wal; I didn't ask about how to avoid the expense of buying a new one but how to make sense of this failure mode. I first thought how nice it'd be to build a keyboard or write a keyboard driver that detects stuck keys so as to mask them out, but it'll go on forever until I press another key.

For fun, watch this guy disassemble and clean his K360 https://www.youtube.com/watch?v=dxl_m94k9ZI

Are we to presume it isn't actually the "f" key that's playing up ?. Else how could you type this thread ... :p
So what key is it ?.

I can feel a Monty Python sketch coming on.

Try new batteries just in case?

Turn the keyboard over and smack it to dislodge cookie crumbs?

Test different keyboard?

alt-102 I have a laptop. I use the wireless keyboard as a remote control. I listen to stuff on my computer while I'm cooking, eating, cleaning, doing chores...

Tried.


Tried.


The other 2 work.

You miss the point: I didn't ask for a solution but an explanation.

It’s broke... ;)

I had an idle hour so I took it apart, per the YouTube video. I didn't take all the keycaps out but got it clean enough to work.