> be resynchronized... well, you know what I mean... a 1% error on
> a bit stream using manchester encoding where the signal is sampled
> twice per period (like jinx's system), will loose sync within 50 bits
> or so...

That's very true. The downside of not periodically detecting edges
is that synch will be lost. For the application I described I've sent
data streams of 100 bytes as a test (actual application is 6 bytes)
without loss, but the simple "time and sample" method is not what
should be used

That said, I've analysed many receptions in all weather conditions
and temperatures (which affects the PIC's clocks) and with various
transmission blockages (wet house in the way etc) and yet to have
a failure at 70m, using just a single sample point

As I mentioned, an upcoming half-duplex project will need a better
protocol, so I'll be toughening it with some of the suggestions

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