S-TEC 30 Autopilot

[Cadstat]

My S-Tec 30 has been working just fine but last time up the heading 'bug' on the DG wouldn't update the heading. It locks on the heading and alt initially but won't accept a course change. It drifts to the left. I cycled through the system several times with the same out come. Where do I start looking for the problem?

[Pat Hatch]

John,

I'll bet the problem is actually your DG and not the S-Tec 30. I have your setup exactly and recently had this problem. I wasn't real sure, but I suspected the DG, which I had initially bought overhauled. Sigma-Tek recently had an exchange deal for a brand new DG for about $700 plus your core, so I took the deal and the heading bug now works perfectly. Just a data point for you.

In my case, the heading bug just quit working one day. I could still use the heading steer knob (ST - Stabilizer mode) on the autopilot, but as soon as I went to heading select, it would quit working. Chances are, if your heading steer (ST) is working then the problem is probably the DG.

Hope this helps.

[Cadstat]

I pulled the DG. Sent it to Kansas and they sent it back saying nothing wrong. I put every thing back this week end and now I have nothing. The S-tec won't even power up.
I don't know what to do next.