Century 1 autopilot S turning on GPS

[Rebel Lord]

The century 1 autopilot On my cherokee S turns
When it on tracking mode with the OBS on gps with my 530.

So I was doing research on the century 1 it says that s turning while tracking cdi on gps could happen if the cdi width is to narrow or to wide.

So to fix this how do I adjust the CDI sensitivity on the GNS 530, is there even a way? I’m very new to the 530.

 

[AlleyCat67]

I can't answer your direct question. But I recently had our Century 1 serviced, and cleaning the brushes in the servo motor helped solve an "s turn while tracking" problem. Basically, small voltages (corresponding to small course deviations) couldn't drive the servo motor, so the servo would only respond when the deviation grew larger, causing overcorrection. Cleaning the brushes made the system more sensitive, and allowed the servos to respond to small, early deviations. You might check that also.

 

[Indiana_Pilot]

What exact model of the Century 1 do you have? Mine is this one.. Is yours the same one? https://www.centuryflight.com/products/systems/century-i-autopilot.html

Is yours just interfaced to the 530 via the CDI?

 

[Rebel Lord]

What exact model of the Century 1 do you have? Mine is this one.. Is yours the same one? https://www.centuryflight.com/products/systems/century-i-autopilot.html

Is yours just interfaced to the 530 via the CDI?

Yes, and yes that’s what mine looks like

 

[chemgeek]

Does it always oscillate around the selected course, or just after an intercept? Rate-based autopilots without GPSS require that the CDI be within a dot or so and course to be within 10 degrees of desired track in order to capture properly. Otherwise, if capture occurs at all, the autopilot course will enter a damped oscillation about the desired track. That's how my STEC-20 works without GPSS.