On 23 May 2006 08:31:29 -0700, "
wrote:

This was after I tweaked the PID to get rid of the oscillations but
still had some average position errors...

I guess with a digital system it would be easier to optimize. Mine was
all analog... and only one op amp, so the settings interacted :-)

Hi Dan,

If anything, going digital has all the prospects of thrashing the
antenna into shreds. The oscillations you speak of are eminently
suited for an analog solution - you simply have to understand the
nature of resonance, coupling (over, critical, and under), and attack.
If you don't, translating them into binary code will be impossible.

For instance, your average position errors were probably due to
under/overshoot and a too heavily dampened system with too much gain.
No computer program is going to improve that.

73's
Richard Clark, KB7QHC