Florent THIERY wrote:
>> Actually the 500Hz comes from the 2.4GHz signal which is pulsed at 500Hz (a
>> frame is sent each 2ms, thus 500Hz).
>>
>
> Would'nt a passive "passe-haut" filter remove it? (no idea how it's
> called in english :p)
>
> http://fr.wikipedia.org/wiki/Filtre_passe-haut
>
Follow the link to the english page ;-)
And you'll discover it's called High-pass filter
http://en.wikipedia.org/wiki/High-pass_filter
But if you skip everything belog let's say 550Hz you'll miss a big part.
Think that the musical A ("la" en français) to tune instruments is only
440Hz
(as well as the phone tone)
500Hz is just in the middle of the useful audio band that's it :-(
What you need is a notch filter:
http://en.wikipedia.org/wiki/Band-stop_filter
but getting a very narrow one is not that obvious.
Depends how good is the AVR on audio processing...
Otherwise analog ones are possible, starting from the very basic RLC filter:
http://www.everything2.com/index.pl?node_id=1391618&lastnode_id=0
Phil
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
tux-droid-user mailing list
[EMAIL PROTECTED]
https://lists.sourceforge.net/lists/listinfo/tux-droid-user
