SG-235 Smartuner - SGC

SG-235 ManualWhen installed in high performance turboprop or jet aircraft, the Smartunerwill operate well with a shunt fed antenna. This is generally a 13 foot piece ofmetal which mounts on the fuselage of the aircraft and is grounded to the aircraftat one end. The device looks something like a towel bar on the undersideof the aircraft. The Smartuner will also match well the more common wireantenna from fuselage to vertical stabilizer (and continuing to a wingtip ifdesired) and a long wire antenna under the tail rotor of helicopters. This longwire approach has proven very effective on Bell JetRangers and LongRangersin particular.5.4 LOW PROFILE, HIDDEN AND COVERT ANTENNASThere are two general types of low profile, hidden and covert antennas.¥ The first group is the paramilitary user who will wish to operate from a residenceor commercial building without drawing attention to the fact that longrange HF communication is in process.¥ The second class of covert antenna user (and a larger group) is the amateurradio community which finds itself more restricted almost daily by covenants,building codes and tenant requirements.We will consider a typical residential home and point out covert antennaswhich have been used very successfully for intercontinental communications.As you review the diagram on the following page, remember that the antennasused include both groundless loop type antennas and those which require acounterpoise (ground).A. If a flag pole is made of PVCpipe, it is easy to tape a large gaugewire to the inside of the pipe and usea good counterpoise. Typical flagpoles are 25 to 35 feet in height andoffer excellent performance on allbands.B. The down spout, rain gutterantenna works well if the piping andgutter are aluminum. You may wishCouplerAt least three ground radialslonger than the flag poleSGC Inc. SGC Building, 13737 S.E. 26th St. Bellevue, WA 98005 USAP.O. Box 3526, 98009 Fax: 425-746-6384 Tel: 425- 746-6310 or 1-800-259 7331E-mail: sgc@sgcworld.com Web site: http://www.sgcworld.com31© 1998 SGC Inc