Jinx wrote: > not. Perhaps there's some measurement like phase shift > that needs doing, and which could be done digitally, rather If it is a fairly narrowband signal, centered on 50kHz, maybe you could mix it down to a lower frequency, say 1kHz, then do the processing, in the same way that a radio mixes the RF down to an IF where the gain/filtering stages are easier. As long as the "IF" is high enough that any side bands are preserved you should be OK. HP network analysers work like this, because the amplitude and phase information is not destroyed by the mixing process. TV nature programmes also use this sort of technique to give the viewer some idea of how, for example, a bat might sound to another bat, by mixing the battie sounds down to the human audio range. All the best...Mike. ----- Original Message ----- From: "Jinx" To: Sent: Tuesday, January 13, 2004 7:28 PM Subject: Re: [PIC:]18F452 100khz sampling frequency > > >This is just a guess, but I think he wants to digitize the > > >50KHz signal and do some processing on it > > I was assuming that this was some known tone from a HF > source (eg bat, ultrasonic transducer, dolphin, Barry Gibb), > in which case it's enough to know that the signal is there or > not. Perhaps there's some measurement like phase shift > that needs doing, and which could be done digitally, rather > than trying to determine the analogue quality of the wave. > > Maybe the OP can fill us in a little > > -- > http://www.piclist.com hint: The list server can filter out subtopics > (like ads or off topics) for you. See http://www.piclist.com/#topics -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics