Radio Technique
NEW TOOL. Jack Albrecht, formerly Sales Manager for Kraft, figured out how to modify the Kraft SRF module (synthesizer) so that it puts out AM instead of FM. Then he got one from Vern Mensimer of Hayes Products, San Marcos, CA (telephone 619/744-8546) and modified it for me. In case you hadn't heard, Hayes is the company which bought Kraft and is liquidating the inventory (no servos). Thank you, Jack! This gives me a first-class tool for testing RC systems (especially since my buddy, Bob Aberle, also has one). My first move was to check its output. On my oscilloscope, it looked like a high-quality, 100% modulation, narrow-band AM. The output is a nominal 400 mW.
Radio Technique
QUESTION OF THE DAY: How do we improve interference resistance? Some people believe that we have more interference today than we had 10 years ago. Well, they are wrong! We actually have a lot less interference than before. We also have more people trying to use fewer flying fields, which pushes us closer together and makes modeler-to-modeler interference more noticeable. Ten years ago we had seven RC channels on 72 and 75 MHz. Four were assigned to Aircraft Only, and three were shared with cars and boats. All channels were shared with other services. Given today's explosion of interest in RC cars and boats of all kinds, what sort of interference do you suppose we'd have if the old situation had continued?
Simple Structural Test Techniques for RC Aircraft
SO FAR AS I KNOW, there is no college course in test engineering, and this column is not intended to serve in its place. An approach at that level would have too many pre- and co-requisites in terms of mathematical skills, physics, chemistry, geometry, economics, law, drafting standards, machine shop practices, and so on. In this series I will concentrate on structural test techniques for RC models, with digressions into related subjects when I think it is necessary, keeping the mathematics simple. This is the first digression.
Radio Technique
INSTRUCTOR PILOT. The mechanics of RC flying are quite simple. The student pilot must learn to see what the airplane is doing, and believe. A certain amount of eye-hand coordination must be developed. The student also needs to understand some principles of aerodynamics and kinematics in order to be able to predict what the machine will do. What must the instructor pilot do? The most important thing he must do is build up the student's confidence. He has other tasks as well, which we will discuss below. One of the photos shows John Kleisler with an ST .29-powered biplane which he has designed and built. John's father, Philip, has been my friend for over 20 years. During most of that time, Phil has concentrated on designing, building, and flying RC Sailplanes.
Radio Technique
INTERFERENCE-FREE GROUP. I've spent most of the month of September sitting at my computer working on programs to solve Frequency Committee problems. I'm not its chairman any longer (Fred Marks is), but I maintain an active position as a member of the committee as well as being the District II Frequency Coordinator. As a fallout of the above effort and of responding to requests from my friend Norm Rosenstock as well as from Jim Sears (AMA VP for District VI), both of whom asked for "a list of frequencies, all of which can be operated at the same time without interfering with one another," I offer the following:
