POSITIONING THE RECEIVER AND BATTERY: It's a generally accepted practice to position your receiver and battery to help balance the model properly. It doesn't make any sense to use lead in the nose when moving the battery and receiver well forward will accomplish the same thing without adding "dead weight". Sometimes you can't move the radio components far enough to completely balance a model, but when it comes to saving weight, every little bit helps! The best location in the fuselage for the receiver and battery can't be determined until your model is completely finished. Shift the components fore or aft as necessary to balance.

CUSHION YOUR RECEIVER: The receiver is the "heart" of your radio system in the model and should be well protected from vibration and potential crash damage by wrapping it in several layers of foam rubber. Secure the foam rubber with tape or rubber bands. Some modelers also put their receiver in a plastic bag to protect it in the unlikely event that the fuel tank ruptures.

ANTENNA INSTALLATION TIPS: The receiver antenna should exit the model, on the side opposite the engine exhaust, at a point close to the receiver. For best reception it should be kept as far away from the servos and any other wiring or cables as possible. If the radio manufacturer has furnished an antenna strain relief fitting for inside the fuselage, be sure to use it. Also, it is not a good idea to route the antenna out through the wing opening because vibration between the wing and fuselage can wear away the wire. Outside the model, run the antenna to the top of the fin or the tip of the stab. Do not glue the antenna to the model! A simple way to attach the end of the antenna to the fin is to tie a small rubber band to it and then loop the other end of the rubber band through the fin/rudder hinge line. This allows a certain amount of give in case the antenna is snagged by accident. If the antenna wire is too long, don't cut it off! Just let the excess hang free behind the model. The antenna length is predetermined by the radio manufacturer for best signal reception. Shortening or lengthening the antenna wire can detune the receiver.

BELOW: Don't underestimate the importance of proper antenna routing. Use the strain reliefs provided with your radio.

BATTERY INSTALLATION: Like the receiver, the battery must be wrapped in foam rubber to insulate it from engine vibrations and mounted in the fuselage so that it can't shift around in flight. Think of the wild maneuvers your model may be subjected to and it's easy to imagine the forces trying to dislodge that heavy battery and throw it on top of the servos. Use a piece of scrap balsa glued across the fuselage to hold the battery and receiver in place. The wood can be easily broken away later if you need to remove these components.

MOUNTING THE SWITCH: The receiver on/off switch must be accessible from the outside of the model! It is a common mistake on the part of beginners to mount the switch inside the fuselage with no way of turning it off and on when the wing is on the model. They assume that they can simply turn on the radio when they first arrive at the field, put the wing on, fly several flights, take the wing back off, and then turn the radio off. Wrong! If you try that, somewhere between the first and second flight the battery will go dead and the model will crash! Always turn the receiver and the transmitter off when not in use. Every minute that the radio is left on between flights is one less minute you can fly.

There are two acceptable ways to mount your receiver switch. You can cut a hole in your fuselage side and then bolt the switch directly on the inside wall, with the toggle portion sticking out through the fuse side. Or you can mount the switch internally (some servo trays have a spot for the switch) near the center of the fuselage and use a piece of music wire that extends outside the model to turn it on or off. Set up an internal switch so that pulling the wire out turns the radio on; pushing the wire in turns it off. With either type of switch mount, make any holes in the fuselage side on the side opposite the engine exhaust.

FINAL RADIO CHECKOUT

Now that your radio installation is complete, operate all controls to full movement and listen to the servos. If overloaded or stalled, they will buzz or hum loudly. Another sign of excess load on the servo is a pushrod that sticks or arches up or down from the servo pushing it against a dead end. Inspect the movement of all pushrods carefully. They should not be rubbing against each other or against the model structure to any degree. Examine the servo arms closely at full movement to see if the pushrod ends are binding against the center post of the servos. Locate the cause of overloads and eliminate them. Overloaded servos eat battery power at a high rate and could cause you to run out of battery power sooner than expected. Servos can also be damaged by continual overload.

Double check that all of the controls are moving the right direction and that the control surfaces move the correct amount. Most kits include the recommended control surface movements for test flying somewhere in the kit instructions. Adjust your linkages to provide the correct amount of deflection by moving to a different hole on the servo arm or control horn. You should carefully adjust all of your pushrod linkages so the control surfaces are in their neutral position when the transmitter sticks and trim levers are centered in neutral. Hurrying this step can lead to some wild test flights!

Check to see that all wiring is neatly tucked away to keep it from flopping into the servo output arms or pushrods during flight. Make certain that there is no strain on any of the wiring from being pulled too tight. If your model has ailerons, make sure that your aileron extension chord doesn't interfere with the servos when the wing is put on. Locate the charging jack so it is easy to get to.

RIGHT: This diagram illustrates how to measure control surface throw properly, and explains how to adjust the amount of throw.

TYPICAL CONTROL SURFACE AS VIEWED FROM END ALWAYS MEASURE CONTROL THROW (DISTANCE "X") AT THE WIDEST POINT OF THE CONTROL SURFACE. TO INCREASE CONTROL THROW: MOVE R/C LINK "IN" ON CONTROL HORN (USE THE NEXT HOLE CLOSER TO THE CONTROL SURFACE). - or - CONNECT PUSHROD FURTHER "OUT" ON SERVO OUTPUT ARM (NEXT HOLE FURTHER OUT FROM CENTER). TO DECREASE CONTROL THROW: MOVE R/C LINK "OUT" ON CONTROL HORN. - or - CONNECT PUSHROD FURTHER "IN" ON SERVO OUTPUT ARM.