Roger Long wrote:
I haven't given much thought to the innerworkings of autopilot control
circuits. I've never heard of a speed input but do know that "rate based"
autopilots are considered better than "heading based" units on aircraft. I
would imagine from the name that they adjust their respons according to the
speed of the heading change which should produce similar results to a speed
input.

You might be interested in this bit of electronics tinkering I did last
fall:

http://home.maine.rr.com/rlma/ST1000mods.htm

--
Roger Long

Very clever, Roger. My unit, I believe it was a Sportpilot, used a
motor to drive the wheel. It must have been fitted with limit switches
as the motor didn't seem to overheat, but the rate of response was, as I
said, too slow when trolling.

I thought about going into the controller and adjusting it, probably
through software, but it probably use a surface mount processor and it
was just too much work. I called Raymarine or whoever made the thing
and they weren't interested in helping. As I said earlier, I sold the
boat and got something a lot better (at least in my judgment).

I could live without an autopilot now (and I may), especially since this
boat tracks well, but I can never leave well enough alone...

--

Larry
rapp at lmr dot com