> ... you calculate the characteristic impedance of your
> trace based on your PCB properties, copper weight, trace width, etc.,
> and then you put a resistor of that value at the end of your track.

Vot's dis calculate stuff den?
- Presumably a bit of thought and a look at the step voltage at
reflection on the scope trace would allow you to determine the actual
impedance.
- And changing the termination resistance incrementally and observing
the changing waveform would allow you to check the result and whether
you were "zeroing in" on the correct value.
- The scope would also allow you to check for multiple reflections. BUT
- The scope has a good prospect of influencing the result.


                     Russell
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