The purpose for this procedure is to enable the autopilot to track VOR and LOC signals with a centered nav indicator needle. It may be necessary to manually overpower the control wheel back to center of travel range if the control wheel turns far enough and hits the limit stops.Ĥ) This adjustment procedure is not for the faint of heart and is an easy procedure for an experience avionics technician to accomplish but can be exasperating for an unexperienced person to do properly. However, if there is any rotation of the control wheel then very carefully and slowly using that small screwdriver adjust the potentiometer to stop the control wheel rotation. Let the NAV mode of the autopilot time out to the SOFT mode.ģ) If the control wheel is not turning left or right - no adjustment of the balancing potentiometer is necessary - every thing is correctly adjusted. This insures that the left/right drive to the autopilot form the VOR is truly zero. The way this adjustment is made is as follows:ġ) Center the heading bug (if a standard DG) or the course pointer (if and HSI) under the lubber line.Ģ) Turn on the autopilot and put it in the NAV mode but leave the VOR radio turned off that coupled to the autopilot.
With the screw removed, the potentiometer can be adjusted with a very small flat head screw driver (not a hex wrench)that will fit in the hole but the shank of the screwdriver as I remember needs to be about 1.5" long in order to reach the potentiometer adjustment. There is a balancing potentiometer behind the screw in the upper right corner of the control head. The face plate for the ST60-2 autopilot control head has four small Phillips screws in it, one in each corner. The roll compensation procedure he refers to is balance out the zero turn rate output of the S-TEC turn coordinator gyro when the autopilot is in the nav mode - not the heading mode. Please let me know what you have in order for me to give you further advice.Īlso, I need to correct the post by Garry Sondergaard. You did not indicate if heading gyro is the S-TEC DG or an HSI. Super Low time Factory Engines 249/249 SFRM (2018) 119/119SPOH (2019) Late E Model with Garmin 430, Garmin MX20 MFD, STEC 50 Autopilot upgrades. I also own a 1964 S35 Bonanza with a S-TEC ST60-2 autopilot.