Radio Technique
A LITTLE GAME for your club meeting. First, I'd better give you some reference information: As of December 20, 1987, the FCC (Federal Communications Commission) mandates that we abandon 72.08, 72.16, 72.24, 72.32, 72.40, 72.96 and 75.640 MHz. During 1987 you will either convert your old wideband AM (OWB-AM) sets to one of the existing even-numbered, high-bandwidth channels (RC38-RC56), or you will junk them. The game we're going to play can help you make the decision. Note: You will not convert those old RC systems to the new 1988 low band channels. As of January 1, 1988 the AMA will sanction even-numbered RC channels from RC12 through RC58, less RC36. As I explained last month, it is intended that only narrow-band equipment will be used in the low (RC12-RC34) channels. There is no restriction against using narrow-band equipment in the high band (RC38-RC58), also-in fact we recommend that you do it.
Radio Technique
HOW FAST is it turning? This month's subject is tachometers. The first one I remember using was called a Vibra-Tach. It looked like a small X-Acto knife, but a piece of music wire extended from the end where we usually see a blade. To use the tool you rested it on the engine and slid a ring which encircled the handle back and forth until the free end of the music wire took up a large oscillation. The body or "handle" was engraved with an rpm scale, and you read the step nearest the position where the ring had to be to let the wire show the wide vibration. It worked on the principle of resonance. When the mass, length, and stiffness of the wire combined to show the wide vibration, the free part of the wire was in resonance with the engine. There were several difficulties with this instrument, among them being finding access to a cowled engine and the unavoidable effects of prop wash.
Radio Technique
LET ME introduce George P. Steiner of Sacramento, CA. George is a member of the AMA Frequency Committee, a retired communications engineer, and is well-equipped with electronic tools-including his personal spectrum analyzer. George does his RC repairs under the name GSP (for George Steiner Products). George has been kept very busy for the past two years performing hundreds of laboratory tests of RC systems for the Frequency Committee. One interesting result of his testing is that he has found that his test results match the Aberle/Myers field test results that Bob and I have been reporting to you.
Radio Technique
"WHAT new radio should I buy?" More than half of the letters from readers this month have asked the same question, "What RC system can I buy-right now-that will be usable in 1991 and beyond?" One possible answer is: "If you want a general-purpose, airplane-only RC system, then buy a Futaba Conquest PCM system on channel RC12." Now, why did I pick that particular system and channel? Our tests (Aberle, Myers, and Steiner) have shown it to be a good, low-to-medium-priced system which includes a narrow-band receiver as well as a narrow-band transmitter, and it provides all the usual functions (including servo reversing) plus a good, built-in "failsafe."
WRAM Show '87
FEBRUARY 21 and 22 were beautiful, warm, sunny days (the heavy snowstorm held off till Sunday night, as predicted). This year the WRAM Show moved to the Yonkers Race Track, which provided much better parking, modern facilities, and the ability to have everything on one level. As I am somewhat restricted in my movements this year (due to the fact that I am recovering from an illness), I really appreciated the change from the usual three-floor setup. On the other hand, this year's arrangement put three rows of booths at the end containing Byron Originals, Ace RC, the AMA booth, and the food concession. This created some "choke points." But the rest of the show had the booths two across, which was fine. Taking the whole show into consideration, you have to agree that the layout was much improved.
