Final Radio Installation - GREAT PLANES Extra 300S Instruction Manual

6. Shift the radio components until you can get the model
to balance as closely as possible to the indicated balance
point. This isn't the final C.G. check, but it will enable you
to minimize (or altogether eliminate) the amount of lead
required to finally balance your model. Our model using an
O.S. .46 SX balanced with the servo tray as far aft as
possible, a 500mAh battery pack just in front of the servo
tray and the receiver just behind the servo tray. Your model
may vary.
7. Glue the servo tray in position. Temporarily remove
the battery pack and receiver noting their location to
achieve the correct C.G.
8. Use one of the scrap pieces of pushrod wire
(approximately 6" in length), to make the front wire pushrod
for the elevator. Make a 90° "L" bend in the end of the wire
and secure it to the front of the elevator pushrod dowel with
a 1-1/2" long piece of heat shrink tubing and thin CA.
9. Place a one-arm servo horn on the elevator (middle)
servo on the servo tray. Position the elevator servo in the
servo tray so the elevator pushrod will run straight down
the middle of the fuselage when connected to the servo.
Drill 1/16" holes and mount the elevator servo to the servo
tray.
10. Mark, bend, then cut the excess off the pushrod the
same way you did for the ailerons, and connect it to your
elevator servo with a nylon Faslink.
11. Connect the rudder pushrod to the rudder servo the
same as the elevator using heat shrink tubing to secure the
pushrod wire to the dowel and using a Faslink to connect
the wire to the servo. Drill 1/16" holes and mount the rudder
servo to the servo tray. You can see the rudder servo in
following photos.
12. Place a servo horn on your throttle servo. Cut the
throttle guide tube approximately 1-1/2" in front of the
throttle servo horn.
13. Remove the cowl and guide the thin throttle pushrod
wire through the throttle guide tube. Make a "Z-bend" on the
end of the pushrod wire and connect it to the throttle servo.
RETAINER
14. Cut the throttle pushrod wire to the correct length,
then connect it to the carb arm using a screw-lock
pushrod connector and a 4-40 x 1/4" SHCS. Secure the
screw-lock pushrod connector to the carb arm with a nylon
retainer.

Final Radio Installation

1. (Refer to this photo for mounting your radio.) Connect
your servo cords, switch and an aileron extension cord to
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