I’d like to write a monthly column that addresses the more technical side of our hobby. I am probably more addicted than most, but I really enjoy the how’s and why’s of our toys and would like to share as much as I can with you. I take great pleasure in tweaking whatever project I am working on to get the most performance out of it whether it be radio setup, or getting an engine to run perfect or dialing in C.G and control throws. What I would really like is for people to submit a question or topic that they may be interested in, and I could write about it here. Some columns may go hand in hand with a live demonstration at our monthly meeting, perhaps something like an introduction to composite part making or other relevant topics.

To get the ball rolling I thought I would touch on some radio basics that there still seems to be some confusion about, and some reluctance to use. There really is no excuse for not using whatever features your radio has to offer. Even the most basic aircraft can benefit from some of the advanced features that even the mid level radios seem to be equipped with nowadays. My goal here is to hopefully explain some of those features a bit better and inspire some to give it a shot. Most people don’t realize that the ergonomics of your transmitter can be changed quite a bit to suit your flying style fairly easily. For instance, the control stick length can be adjusted to a more comfortable position. As a “pinch” type pilot I prefer my sticks very short. If you are a “thumber, you might like them a bit longer. If you tend to be a jumpier flyer, longer sticks can smooth you out and conversely, 3D pilots generally like them shorter. The point is you might not realize what you are missing, so tweak them and find out. Another stick related item is tension. Many radios allow you to tighten or loosen stick tension to suit your style as well. Jumpy/precision guys like tighter, 3D looser. I prefer them on the tighter side. Your switches can also be rotated slightly in the case to be less cumbersome to flip depending on whether you pinch or thumb. The best switch flipping path may not always be straight up and down.

Another area to look at is exponential, or expo for short. I know, I know seems mundane but in reality it seems to be a bit misunderstood underutilized. Just recently I helped a fellow member adjust expo values with favorable results and that got me to thinking it’s not as widely used as I had assumed. What expo does is essentially “soften up” the movement of the control surface in relation to the movement of the stick around the neutral point of the controls. This is needed because of the way our servos act our flight surfaces. The servo takes rotary motion (the twisting of the servo arm) and transfers it to linear motion (back and forth of a pushrod). This inherently causes some loss of throw as you reach the ends of the travel as the pushrod moves less back and forth and more in towards the center of the servo. In fact if you do not use any expo, a standard set up will actually have negative expo and be more jumpy around neutral! A good rule of thumb is that it takes 20-25% expo to get back to a linear motion. I never use an expo value of less than 35% on low rate and as high as 60-70% on some models. My racer runs about 45% on all surfaces. Give it a try; you might be in for a treat. (Ed. Futaba uses the opposite numbering for this feature, negative values result in a softening of the controls. If in doubt, ask someone for help)

I’d love to hear from you. If you guys find any of this stuff helpful drop me a line. I take requests.