September 2000 QST

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The elegant Butterfly with its ATVpackage attached.Equipment SuppliersSupercircuitsOne Supercircuits PlazaLeander, TX 78261800-335-9777http://www.supercircuits.com(cameras and transmitters)Edmund Industrial Optics101 East Gloucester PikeBarrington, NJ 08007800-363-1992http://www.edmundoptics.com(cameras and optics)PC Electronics2522 Paxson LnArcadia, CA 91007http://www.hamtv.com(transmitters, GPS overlay boards andcameras)Tower HobbiesPO Box 9078Champaign, IL 61826http://www.towerhobbies.com(model aircraft and supplies)The ATV-equipped Tower TH60 ready fortakeoff.The KSAT rocket and launch team.These steps were sufficient to guaranteeno loss in control range for my RC aircraft.More stubborn cases may requireshielding the receiver, decoupling eachservo lead with feed-through capacitors orchokes where the lead enters the shieldedreceiver compartment and inserting a lowpassfilter in series with the antenna lead.Before flying with ATV gear, carefully“range test” the system on the ground withthe engine turned off. A typical test involvesremoving or collapsing the transmit antennaand backing away from the aircraft whileobserving the control surfaces. Tests shouldbe performed with the ATV transmitter onand off to make sure that the maximum controlrange has not been compromised.We installed the ATV gear only on aircraftthat had already been provenflightworthy. After installation, the centerof gravity was carefully checked to ensurethat the additional gear was at the correct44 September 2000location as indicated on the airplane plans.The greater wing loading caused longertakeoff and landing rolls, higher stallspeeds, sluggish climb performance and adegraded glide ratio. Rudder trim becamevery important and it was necessary to addmore rudder for coordinated turns. TheTH-60 flew best when the control transmitterwas set up to automatically mix rudderdeflection with the ailerons.If the camera is mounted behind theengine, fuel spray can become a problem.A microscope slide or neutral-density filtermakes an excellent windscreen to protectthe camera lens, but it can becomefogged in only a few minutes if the fuelspray is excessive. Exhaust is the main culprit,and the muffler should be positionedon the opposite side of the airplane fromthe camera. To keep fuel spray off the microscopeslide window on the bottom of theTH-60’s fuselage, I had to install a triangularbaffle ahead of the window. Significantfuel spray can also come from thecarburetor. This can be reduced by installingan air filter. Engines that use crankshaftbushings instead of sealed bearings sprayfuel from the front of the engine. Cowlingthe engine or using a ball bearing enginewill fix this problem.We discovered that the computerizedaltimeters used to deploy the parachutes onthe rockets were susceptible to interferencefrom the 2-meter hand-helds we used tocoordinate launch activities. Chute-deploymentfailure and pre-launch chute deploymentwere problems before we caught onto what was going on. We lost our first twoATV rockets to this problem, even thoughboth rockets contained redundant altimeters.Fortunately, the rockets came downin the (planned) remote area, and the crashwas a non-event. The rockets and allonboard equipment were a total (and spectacular)loss. In the future, the altimeterswill be shielded and all connecting wireswill be shielded and decoupled with bypasscapacitors and ferrite chokes. All handheldswill be kept at least 50 feet from thelaunch site. Careful checks will be made toensure that the 70-cm ATV transmitter can’tcause similar problems. Additionally, wewill be installing simple backup timers todeploy the chutes if the altimeters are unableto function for any reason.PrecautionsI don’t want this to sound too much like“don’t try this at home,” but in reality, flyingmodel aircraft and rockets can be dangerousand should be undertaken only byqualified individuals. Both possess sufficientspeed and energy to cause injury,death or extensive property damage. Modelairplane engines and propellers can causeserious hand injuries. Flying RC aircraft isa difficult skill that is within the reach ofmost individuals, but may take years tomaster. Launching model rockets thatweigh more than 1500 grams or carry morethan 125 grams of propellant is subject toFAA regulation. Additional restrictions apply:See FAR Part 101 of the Code of FederalRegulations for more detail. Rocketcomponents and chemicals for larger motorsare available only to individuals certifiedby Tripoli Rocket Association or TheNational Rocket Association.This article is meant to share experiencesand prompt a discussion of the technicalissues involving airborne ATV experimentation.It should not be construed as a“how-to” cookbook. This activity involvesrisks, and individuals participating in thisactivity do so at their own risk.You can contact the author at 10227 MtCrosby Dr, San Antonio, TX 78251;scerwin@swri.org.
By Eric Jamieson, VK5LPThe RossHull StoryOne of the greatest VHF/UHF radiopioneers of the 20th centurywas an Australian-born amateur.Ross Hull is best known for his pioneeringwork in the field of developmentof the VHF and UHFspectrum, in particular equipmentfor the 56 MHz amateur band and later forthe 112 and 224 MHz amateur bands. Thesewere the bands offered to the amateurs duringthe period between World War I andWorld War II. Initially they were shunnedby the professionals due to their perceived“line-of-sight” limitations.While much of Ross’s developmental worktook place in the US, he was an Australian, bornin Melbourne in 1902. Although he was trainedto be an architect, early in his life he developeda great interest for radio, Amateur Radioin particular. By 1922, he had progressed tobecome one of Australia’s best achieving amateurs,being the first to receive signals fromamateurs in the US.He firmly believed in the WirelessInstitute of Australia and became its FederalVice-President in 1924. Later he wasappointed Secretary.In 1925, the Victorian Division of theWIA formed a committee to undertake teststo establish contacts with ARRL stations inthe US. The committee consisted ofHoward Kingsley-Love, 3BM; Ross A.Hull, 3JU; W.F.M. Howden, 3BQ; E. K.Cox, 3BD and C. Philpott. The VK prefixwas to be added to their call signs later. 1On 25 July 1925, Australia was visitedby the US Naval Fleet at Melbourne. Thevessels included the flagship Seattle withstation NRRL aboard manned by Lt. FredH. Schnell, USNRF, and 1MO-1XW wasgreeted as the first ARRL contact by RossA. Hull, A3JU and H. Kingsley-Love,A3BM, and others. The latter was editorand the former associate editor of ExperimentalRadio and Broadcast News.1 Notes appear on page 47.The US Recognizes his ValueAs the result of meeting Fred Schnell,Ross was determined to see America. In1926, in his capacity as Secretary of theWIA, he visited the United States to studyAmerican radio activity with an emphasison Amateur Radio. The ARRL was quickto recognize his potential and appointedhim to a junior position in the editorial department,the technical information service.He extended his stay in the US and waseventually appointed to the position of assistanttechnical editor of QST. 2When, in 1928, the Board of Directorsauthorized a special technical developmentprogram at ARRL HQ to devise new apparatusand methods (to meet the trying conditionsthat would confront amateur radioin 1929 when the Washington Conventiontook effect), Hull was the logical man tohead the program. The brilliant success ofthat program is well known to every old timeamateur. Much new gear of Hull’s devisingwas introduced and it is not going too far tosay that his studies over that period revolutionizedthe techniques of that day.He popularized “band-spread” for amateurreceivers and was responsible for thefirst serious use of the superheterodyne inamateur circles as the logical receiver forphone stations. He produced the first practicalapparatus employing the high-Ccircuit for self-excited oscillators, made thefirst presentations in Amateur Radio of100%-modulation and the use of linear RFamplifiers and first introduced the signalmonitor. This technical-development programwas the beginning of real developmentwork in the ARRL Headquarterslaboratory, thereafter carried on almostentirely under his direction.Ross had a flair for building unorthodoxequipment. He popularized the practice ofputting tubes upside down or at unusualangles to shorten leads and was largely responsiblefor the abandonment of bread-boardconstruction in favor of bent metal chassis.The apparatus he built, although often puttogether under the stress of time, was beautifullyconstructed, mechanically rigid and withlosses minimized to work at the greatest efficiency,whatever its purpose. He set the pacein apparatus design for many years.He returned to Australia in 1929 and becamethe technical editor of Wireless Weekly,which was edited by his brother, A. GalbraithHull. Wireless Weekly was the forerunner oftoday’s Electronics Australia.Ross Joins the Staff of QSTHe had been well and truly bitten by theAmerican bug, so he returned to the US andin January 1931 he joined Kenneth B.Warner, W1EH, (Secretary of the ARRL,Editor-in-Chief and Business Manager ofQST) as Associate Editor of QST, a positionfrom which he became the mainspringof the QST editorial staff. Ross Hull had theability to organize and direct; he could keephis eye on the ball and inspire others to dothe same. At the same time he worked likethree ordinary men in the laboratory himself.Here he developed new equipment foruse by W1AL, the ARRL’s own experimen-September 2000 45
Page 6 and 7: September 2000 Volume 84 Number 9C
Page 11 and 12: THE AMERICAN RADIORELAY LEAGUE INCT
Page 14: Get to Know Your Section ManagerThe
Page 18: Cosponsors for S.2183Introduced by
Page 22 and 23: Calling All Holiday Photos!Calling
Page 26 and 27: CORRESPONDENCEYour opinions count!
Page 30 and 31: By David Blaschke, W5UNMBAThe Might
Page 32 and 33: By Bill Wageman, K5MATGrid Chasing:
Page 34 and 35: By Dan Wissell, N1BYTThe OCR II Rec
Page 36 and 37: 34 September 2000 Figure 1
Page 38 and 39: its signal in a general-coverage re
Page 40 and 41: By Dick Goodman, WA3USGThe Monster
Page 42 and 43: Figure 4—Schematic diagram of the
Page 44 and 45: elative power levels of the control
Page 48 and 49: Ross Hull, 3JU, at his station inMe
Page 50 and 51: By Jean Wolfgang, WB3IOSJamboree On
Page 52 and 53: By Lew Malchick, N2RQSchool Club Ro
Page 54 and 55: By Dave Patton, NT1NARRL Board Thin
Page 56 and 57: Summary of Major Board ActionsMinut
Page 58 and 59: Manager, delivered his report on th
Page 60 and 61: ucts, and promote more efficient us
Page 62 and 63: Figure 3—To change your display c
Page 64 and 65: ity suffers. That is, it’s more d
Page 66 and 67: in building a higher-performance re
Page 68 and 69: SHORT TAKESEZNEC 3.0 for WindowsBy
Page 70 and 71: HINTS & KINKSDOX CONTROL FOR A YAES
Page 72 and 73: HAPPENINGSARRL Says Amateur Service
Page 74 and 75: Seminole County to erect a 35-foot
Page 76 and 77: Reviewed by Rich Arland, K7SZQST Co
Page 78 and 79: through an antenna tuner, and was r
Page 80 and 81: to use lighter plug equipped vehicl
Page 82 and 83: PUBLIC SERVICEThe Trials and Reward
Page 84 and 85: HOW’S DX?Tristan da Cunha and Gou
Page 86 and 87: THE WORLD ABOVE 50 MHZInto the 21st
Page 88 and 89: were more than half a dozen 2-meter
Page 90 and 91: health, safety and aesthetics conce
Page 92 and 93: AMATEUR SATELLITESA “Hot” After
Page 94 and 95: Christopher R.Gonyea, KB1AZKGoshen,
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QRP POWERVintage QRPFiring up an ol
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HAMFEST CALENDAR† ARRL HamfestAtt
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Mobile to the Max![You’ve heard t
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75, 50 AND 25 YEARS AGOSeptember 19
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FeedbackA change in scoring in the
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2000 ARRL RTTYRoundup ResultsBy Dan
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RA4CTR 14,674 253 58 ARA6AR 12,042
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Olli’s 2,100,744-point effort dem
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Puerto RicoWP4LNY 150,912 440 131 A
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K7RI868,140 3446 126 B CK7CAR 530,4
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Net Freq Time/Daily/UTC QNI QTC QTR
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GREAT LAKES DIVISIONKENTUCKY: SM, B
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(ARES) training session on Septembe
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third. It will be interesting to se
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136if you’ve changed your callsig
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that this new technology could dist
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our section Web page (www.sflarrl.o
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150support ARRL and the section. Th
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WANTED: Electronic estates, hi-fi,
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ANTENNA HARDWARE - S.S. “U” bol
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TRYLON SELF-SUPPORTING TOWERS: Stee
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September 2000 QST

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