This column is titled Hints, Information Tips and Stuff. I think it’s been a while since I published any Hints or Tips, so here goes. Here’s a little piece of knowledge that I learned from a former club member, John Fischer. Do you know the correct way to ground check your radio?

First you really need two people for a range check, one to watch the plane’s control surfaces and one to walk the transmitter. The transmitter antenna should be extended one segment (approx 7”) for a proper test; this is sometimes dependent on the brand of transmitter but one segment is a good basic rule of thumb. This procedure is something I never knew since I’ve always range checked my radios with the transmitter antenna fully collapsed. Most of my transmitters have plastic cases and therefore the fully collapsed antenna is not a problem. But I do have a Futaba 9CAF, which has a metal case; metal case transmitters need to have the antenna extended one segment. Now, using the wing tip as a direction pointer, walk about fifty feet in the direction the wing tip points. Hold your transmitter away from your body and point the antenna in the same direction as the model’s nose. Don’t point it at the model, as that provides the weakest signal. You want to hold the transmitter so that the antenna is parallel to the ground and parallel to the fuselage. Move the control surfaces. Your partner should be checking for the correct movements and watching for control surface flutter. Any problems? DON’T FLY.

I like to use flexible cable when connecting the servo to the engine throttle arm. The flexible cable allows for a little mismatch between the movement of the throttle arm and the servo arm. On most throttle set ups the servo is pushing the throttle open and pulling it closed. I adjust the linkage for a good throttle close. That way I can remotely shut down the engine, in flight, if there are any problems. Then I check for full open. With using cable, if the servo arm pushes a little too much, the flex in the cable will take up the extra movement. The servo won’t be forcing the throttle against the throttle stop in the carburetor as it would in a “solid” connection. You should leave about 1-1/2 inches of cable open, not in the guide tube, between the servo arm clevis and the cable tube. This will allow for the cable to flex. While we’re on the subject of flex-cable, it also makes a great “fishing” line when you’re trying to thread servo leads through a wing. The metal cable is flexible enough to go around obstacles but it’s still stiff enough that you can still push it. In fact, sometimes I find using the flex-cable easier than a piece of string with a weight attached. Also when “fishing” you might want to try holding that wing or fuselage vertical and let gravity do some of the work. I always like to route my antennas through the inside of model and out the tail. I think it makes for a neater appearance.
Start at the tail, where you want the antenna to exit. Drill a hole the size of the plastic antenna tube. You can usually pick up some antenna tubing at your local hobby shop. Begin at the tail and start threading a metal flex-cable through the fuselage until it comes out in the radio compartment. Now starting from the tail, push the antenna tubing over the flexcable until the tubing comes out in the radio compartment. Finally glue both ends of the tube to the fuselage. You’ll find that if you wrap some masking tape around the tube, apply the glue to the tape and glue the taped tubing to the fuselage walls will give you a more permanent installation. The CA will stick to the tape easier than to the plastic tube. When the glue has dried, remove the flex cable and cut the tube flush with the outside of the fuselage. Finally thread you antenna through the tube and out the tail of the model.

I’ll leave you with this one. Here are some websites that show basic aerobatic diagrams and descriptions. The first one even has thumbnail animations of what some of the maneuvers should look like. I found these while looking up
‘ARESTI’ on the Internet. By the way “Aresti” is last name the guy who invented the diagramming system used in aerobatic competition. Check out these web sites.

Fly Smart, Fly Safe, Larry Dudkowski