Radio Control Systems - Modification of HiTec HS80/HS81 Servo

Follow steps exactly, taking care and time over the job. Click on any picture to magnify and study carefully. Job should take between 10 minutes and 1 hour depending on glue used. Tx - Transmitter, Rx - Receiver.
 

1. Remove 4 fixing screws from base to release top and bottom sections.	2. Remove base panel and top section carefully.	3. Servo contains a small stack of gears. Note the positions for re-assembly.
4. Identify 'End-stop' in the top cap. This plastic node prevents 360 degree rotation of drive.	5. Using a small file, reduce the node until it is flat and inline with the rest of the inner lid.	6. Using a small (1.5mm) drill, remove internal 'stop' from the final output gear - the one that is visible when together.
7. Identify the feedback pot. This is normally the spindle that the final gear sits on. It will have a small notch.	8. Remove the pot from servo (if necessary). On HS-80 this is not required. HS-81 shown here. Don't remove wires.	9. Connect servo to Rx and battery. Switch on Tx with stick centered and trimmers at neutral.
10. Turn the feedback pot until servo motor stops running. Now glue pot arm in place with superglue or glue gun type adhesive.	11. When dry, refit all components and check the servo runs continuously in both directions by moving the Tx stick.	12. Finally replace bottom panel and screw back together. When modifying second servo, connect first as well to get perfect neutral.