Re: [microsound] [.microsound] antennae

[ben nevile <bbn@xxxxxxxx>]

> i'm interested in shortrange radio broadcast (within a 20ft.x20ft.
> room)...going to try to do all the encoding in software


AM is easy, just multiply your (mono) audio signal by a carrier wave
somewhere between 550 and 1300kHz.  if your carrier is at frequency f you
will need to filter out all frequencies above nyquist-f if you want to avoid
aliasing.  (nyquist is half of your sampling rate: 22kHz for most sound
cards.)

the carrier you need to generate an FM signal can't be generated by a stock
audio card because it's in the MHz region.  I don't know anything about
antennae but I'm sure there are schematics galore at your googletips.

bonne chance
b