Radio Technique
MONITORS and monitoring: Mr. Floyd Reed, of the SPARKS (South Pinellas Aeronautical Radio Kontrol Society) St. Petersburg, FL, writes: "Our club president borrowed a scanner and was tinkering with it at our field. He discovered a local radio station broadcasting on channel RC48, a known bad channel in our area for months. He also discovered `a lot of chatter' on RC22, which has been troublesome. What gives?" My response to Floyd is that when performing a test, we must always ask ourselves, "How can this instrument mislead me?" Practically any low-priced scanner available in the U.S.A. would have to be modified to scan the 72 MHz RC channels. Has someone modified the scanner you borrowed?
Radio Technique
Abstract: Battery and charger basics. CARING for NicadTM batteries - Part 1: There are as many kinds of advice about caring for NicadsTM (from here on we'11 call them Ni-Cds our usual editorial style. RMcM) as there are people selling battery-care devices. Some people recharge them only when the batteries are to be put to use. Other people charge them at regular intervals, whether they need it or not. Still other's keep them charged all the time with trickle chargers. Everybody succeeds. Who's right? The nickel-cadmium (Ni-Cd) cell is very tolerant of abuse and neglect, which makes it hard to define "wrong" answers. Its service life, measured in terms of available discharge/recharge cycles, exceeds our needs. "Rightness" is determined by the conditions under which the batteries are used. For example: When you pick up a portable telephone, you expect it to work immediately. Portable telephones have rechargeable batteries that are kept on a trickle charger.
WRAM Show '89
THE FORECAST on Friday, February 24, was for 10 inches of snow by rush hour. Decision time. Should I go to the WRAM Show or wait out the snowfall? Since the van was equipped for the Alaska trip, I reasoned it should be ready for anything. I went to White Plains. This show was held in the renovated Westchester County Civic Center. The renovators did a fine job. There was more room for the show (150 booths), a nicer theater for the movies and for the District II meeting, and more room for the static displays and for the Swap Shop.
Radio Technique
WHAT'S AHEAD? This is part two of the discussion I began last month: Bob Aberle, George Steiner, and I have seen, and tested in various ways, some DC (dual-conversion) Rx, including the new Airtronics receivers, Futaba 1024 PCM, Polk's Challenger 720, World's Expert, Ace, R/C's Model 91, and the old Kraft KPR-8FD. They show some interesting characteristics: 1) Adjacent-channel interference is insignificant to the new dual-conversion (DC) receivers. Gold-sticker transmitters at 20 kHz channel separation (the 1991 situation) have less effect on these new receivers than Silver-sticker transmitters at 40 kHz separation had on the old receivers (the 1983-1987 situation).
Radio Technique
THE AUTHOR of a recent column in another modeling publication took me to task about certain things I had said in my June 1988 "Radio Technique" column. The specific criticisms were that I had called RC crystal swapping "illegal," and that I had claimed that the ICOM IC-R7000 receiver was not good enough to use in measuring transmitter power levels in the tests necessary to certify that a transmitter meets the AMA/RCHA "Gold Sticker" or "Silver Sticker" performance tolerances-and that I was not technically qualified to make the latter statement.
