On 23 Apr 2005 at 5:25, Dave Tweed wrote:

> Russell McMahon <apptech@paradise.net.nz> wrote:
> > Thinking about ECAN (Extra Cheap And Nasty) MODEM ideas.
> 
> Sounds like a really good application for a low-end dsPIC. You could do
> a rather high-quality FSK or DPSK modem entirely in software, with just
> a few passive components to interface the audio to/from the radio.
> 
> Have you looked at any of the modems used in amateur packet radio?
> 
> -- Dave Tweed
> 

	Last year I did a 1200bps BELL-202 modem for a client using the
Atmel ATMEGA8 processor running at 6.144MHz. 
	TX audio generated via PWM and RX demodulation using fixed-point
16bit math as explained on the link below:

	http://www.baycom.org/~tom/ham/da95/d_dspmod.pdf

	Mark Jordan, PY3SS


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