Roger, Bill,

Thank you for your responses!

I had implemented what you have both described, using a switch to select from statically defined rates, but that seems like a very tedious process to get a new plane dialed in. Plus it would be nice to alter rates at different times without having to pre-program them in. What I have set up now is pre-defined expo rates but with dynamically adjustable end rates.

Here is what I did for on-the-fly end point rates:

While the 12FG does not allow assignment of a knob to control the rate or exponential parameters when setting up the AFR, it does allow assigning a knob to the fine tune feature when setting up a programmable mix. With my limited experimentation with mixes it appears that mixes work by scaling the master with the mix function (graph) and adding that to the slave. If the master and slave are the same, then the mix adds a percentage of the control onto itself. Since the knob alters the mix function being applied, the results is dynamic adjustment of the control surface. This appears to work properly by looking at the servo output.

Bill, am I missing something here?

- steve