Fw: Private PIC question

[Terry Fox]

More on PropNet PIC transmitter.

Anyone else interested?
Terry

----- Original Message ----- 
From: "Terry Fox" <tfox at knology.net>
To: "David A Aitcheson - KB3EFS" <kb3efs at gisco.net>
Cc: <tfox at knology.net>
Sent: Wednesday, August 23, 2006 8:46 PM
Subject: Re: Private PIC question


> Dave, thanks for the earlier email as well.
>
> I think it's possible, but receiving PSK-31 would be harder to do than
> transmitting it, at least with any noise on the audio.  A more advanced
PIC
> could probably do it, but I don't have any experience with the DSPic (with
> DSP core) devices.  Most PIC programs that receive begin by amplifying
> and/or squaring the audio, which won't work very well with phase-shift
> keying in a potentially noisy environment.  So, you would need to go the
> more complicated route - A/D converting, then filtering, then looking at
> phase info.  Much more work to do I think.
>
> I was thinking a transmit controller is pretty easy, since you don't need
to
> decode the audio.  Just use a 4-bit D/A from the PIC itself to generate
> psuedo-sine waves, that are then smoothed out with an audio low-pass
filter.
> The character variable-encoding, phase modulation, and other stuff is easy
> to do in a PIC.
>
> I'll think more about it however....
> Terry
>
> ----- Original Message ----- 
> From: "David A Aitcheson - KB3EFS" <kb3efs at gisco.net>
> To: "HAM - Terry Fox - WB4JFI" <tfox at knology.net>
> Sent: Wednesday, August 23, 2006 8:11 PM
> Subject: Private PIC question
>
>
> > Terry,
> >
> >  From another, much smaller group...
> > Could something like this be done with a PIC?
> > I am not up to speed on PIC stuff.
> >
> > Dave
> >
> > > Are any of you withing LOS of another PropNETer to run a test?  Jeff
> > > has added a <ROBOT> feature!!!!  We need to test it out before
> > > releasing it.
> > >
> > > It works like this...
> > >
> > > If your station decodes its own callsign, and captures the callsign of
> > > the station calling you, it will reply (over the air!):
> > >
> > > hiscall hiscall de mycall mycall <Robot>
> > > Please stand by while I attempt to alert the operator.
> > >
> > > We need a couple of folks to test.  Is there anyone on the Developer
> > > list who can help?
> > >
> > > Ev, W2EV
> >
> >
>
>