Peter Onion wrote:
> Put the two 6kHz signals into a phase comparator and you get the
> recovered phase shift data out as the DC component.  I fed this into an
> ADC input on a PIC and decoded the data from there.  The eye diagram for
> the data can be seen at the bottom left in this picture
> http://www.btinternet.com/~Peter.Onion/PhaseData/p002107.jpg

How did you generate that? It looks like an X-Y display on an oscilloscope; I 
guess you used a pair of DACs to drive the X/Y and a timer ISR to draw each frame?

> It was a bit of a lash up, but it did work.
> http://www.btinternet.com/~Peter.Onion/PhaseData/p002127.jpg

Any chance of a schematic, assuming one exists?
I've been looking for a data demodulator for 198kHz for quite a while. Once 
I've got a bit of spare cash (roll on December 25th!), I intend to build an 
MSF decoder and maybe a Radio 4 data demodulator too. AM TRF receivers are 
nice and easy to build, thankfully :)

Thanks.
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