TruTrak Pictorial Pilot - Manual (Page 14)

servo does not move at all, double-check the torque setting (setup screen 2) to make sure it is at least 10. If a servo jitters but
does not actually rotate, check the wiring on the four servo drive lines to that servo for continuity and correctness. If the servo
does not seem to have any torque, check the roll torque control line for continuity and correctness. With a torque setting of 12,
and the autopilot engaged, the torque control line should measure approximately 4.9 volts DC.
Rotate the knob to the left and select a heading approximately 40 degrees to the left. The autopilot will now move the controls
in attempt to cause a turn to the left. Rotate the knob to the right and select a heading 20 degrees to the right to stop the servo.
While the servo is running, check that the servo arm or capstan is properly operating the controls. For servo installations using
an arm, check that as the controls go from limit to limit the arm of the servo remains in the operating range of the servo (a
maximum of 100 degrees total rotation) and that when the controls are centered, the connecting push rod is approximately
perpendicular to the arm of the servo. For capstan systems, insure that the cabling remains at proper tension and is properly
secured as the servo moves the controls from stop to stop. Insure that the servo remains secure in its mounting and does not
flex its mounting bracket as it drives the control to its stops. For installations using an arm, insure that as the servo moves the
control towards the end of control travel it does not cause the main control’s torque tube to flex in any way that could cause
control system lockup at the extremes of servo travel. Insure that any “lost motion” in the linkages is eliminated or minimized,
in order to maximize the performance of the autopilot. Lost motion (dead zone) will result in wandering or slow “hunting”
behavior in flight. Lost motion in the linkage can best be observed by temporarily clamping the servo arm and gently moving
an aileron back and forth, while observing how much aileron movement takes place against the clamped servo.
The next step in the check-out procedure is to verify that the serial input from the GPS receiver is being properly received and
interpreted. With the aircraft outside of any building, power up the GPS receiver and the autopilot. After the GPS receiver
acquires its position, the autopilot display will change from “ – – – ” to “OFF” indicating that valid position data is available.
If the word “OFF” is not displayed, even after it is known that the GPS unit has a position fix, the problem must be diagnosed.
Summary:
ENGAGE AUTOPILOT WITH FLIGHT CONTROL CENTERED,
ROTATE KNOB CLOCKWISE. FLIGHT CONTROL MUST MOVE
TOWARD RIGHT. ROTATE KNOB COUNTER CLOCKWISE,
FLIGHT CONTROL MUST MOVE BACK TOWARD LEFT.
TruTrak Flight Systems Pictorial Pilot Installation & User Guide
December 2009 12 8300-011 Rev B