Alpha-Delta_DX-SWL_使用说明书手册_2012

ALOHADELTACOMMUNICATIONS.INC.DX-SWL Shortwave Sloper AntennaMulti-Band Performance covering Medium Wave AM(.5-1.6 MHz).120MTRS(2.3-2.5MHz,90MTRS(3.2-3.5MHz),60MTRS(4.75-5.0MHz),49MTRS(5.95-6.2MHz),41MTRS(7.1-7.3MHz),31MTRS(9.5-9.9MHz),25MTRS(11.65-12.05MHz),21MTRS(13.6-13.8MHz),19MTRS(15.1-15.6MHz,16MTRS(17.55-17.9MHz),13MTRS(21.45-21.85MHz)The Model DX-SWL antenna is a very unique and very effective adaptation of existing antenna theory.It operates asquarter wave sloper which means the wires are a quarter wave long,or multiples of a quarter wave on each frequencyband.Compared to half wave dipole,the other quarter wave,which is necessary for performance and the proper feedpoint impedance,is made up of the "Down-Lead"wire which is attached.With a quarter wave sloper,the center conductor of the coax is attached to the wires and the shield of the coax is attachedto the down lead.A standard SO-239 UHF connector is provided on the Model DX-SWL for this purpose.Excellentperformance is attained with installation heights of only 20 to 40 feet.By design,the quarter wave sloper is known to be an excellent DX and long haul antenna.The current lobe,which definesthe major radiation characteristics of the antenna,is up high at the feed point and is not subject to attenuation frombuildings,trees,etc.as a vertical antenna whose current lobe is at ground level.At the Alpha Delta location,side by sidecomparisons between the Model DX-SWL and a 32ft commercial vertical with 18 radials show the DX-SWL to be as muchas 10 dB stronger into Europe and Africa.Since a sloper has an optimized low angle radiation pattern for peak DX performance,it will greatly outperform a dipolemounted at the same height,for those really distant weak signal DX stations.The difference can be phenomenal.The Alpha Delta Model DX-SWL is fully assembled,uses stainless steel hardware and UV protected coils andcomponents and No.12 wire.It is designed to survive severe weather environments.Insulators and support rope areincluded.Note:For SWL receiving,the Models DX-SWL/SWL-S do not need an HF sizebeam on top to be a"capacity hat".This requirement is for quarter wave slopersused for transmitting.This is due to the specific impedance requirements formatching transmitter output circuits.Receivers have high impedance broadbandinput circuits and don't have this requirement.For installation details and requirements for transmitting,check our WEB siteand check the information for Models DX-A/B quarterwave ham radio slopers.This information can be found on the home page link“Limited Space High Performance Antennas”.In some installations,in addition to the above requirements,the SWL slopers canbe used for transmitting when used with a wide range(10:1)separate antennatuner.Check with your dealer for details on tuners.The SWL slopers have thesame power rated components as the ham radio models.