40-m-compact-4-square-antenna-ea5avl-11, Anteny

[ Pobierz całość w formacie PDF ]
//-->40m Compact 4-Square Antenna – EA5AVLThe EA5AVL 40M Compact 4-Square Antenna was designed to provide excellent DX communications on the 40m band, utilisingreadily available components and be relatively easy to construct. The antenna has been used very successfully over the 2007-2011 period during the sun spot minimum. DX contacts have been made regularly with EK3 Armenia, 7Z1 Saudi,VK6 Perth, K1 nCarolina, 5F6 Morroco,UB6 Starolpol,YY6 Venezuela VO1 N. Foundland , ZF2 Cayman Is, PY7 Brazil, UN7 Kazakhstan, VE3Toronto, CM3 Havana, YC6 Indonesia, AY1 Qatar to mention just a few.NOTES1. The cross arms can be oriented to any compass bearing to suit personal needs.2. The four 1/4λantenna wires are cut for the 7MHz band using the formula1/4λ(feet) =234/F(MHz).For 7050 KHz this works out to be about 33' 3" feet (10.19m).+Total wire require for antennas & counterpoises = 665 feet ( 202m)3. The four 1/4 wavelength RG213 coax feeds ( VF 0.66) are approx 6.7m ( 21' 11") tip to tip of the PL259connectors.4. Four stiff wire capacity hat spokes are fitted, each one being 0.31m (12") long.5. A 1.22m ( 4' 0") copper earth rod at the mast base earth the relay box & capacitor box.6. There is one anchoring point for each vertical, this could be a heavy brick or long tent peg – there is little tension inthese wires.7. The guy ropes are tensioned to support the whole mast.8.No antenna matching unit required, no rotator required, immediate direction change, low wind resistance.Les EA5AVLProofread by G3YEUGraphics by G8ODE April 2011 iss 1.340m Compact 4-Square Antenna – EA5AVLModel By Igor DL2KQ using GAL-ANA Beta version 0.3 Antenna Modelling ProgramProofread by G3YEUGraphics by G8ODE April 2011 iss 1.340m Compact 4-Square Antenna – EA5AVLModel By Igor DL2KQ using GAL-ANA Beta version 0.3 Antenna Modelling ProgramProofread by G3YEUGraphics by G8ODE April 2011 iss 1.340m Compact 4-Square Antenna – EA5AVLPERSPEX FEED POINT CONNECTOR PLATEAntenna wireapprox 33.25 feetSO 239ConnectorWingnut used to fine tune the antennawirelinkwirePerspex SheetSquareWing Nut toconnect Radials4 off CounterpoiseRadialseach 33' 3" longHPLAN VIEW OF ANTENNA SITENorthPerspex feedpoint connector plate1/4 Wavelength50 Ohm coaxesMast top spreader cross arms4.88m ( 16'0")WestAntennaInsulator5.19m(17' 0")5.19m(17' 0")EastSouth antenna wire& coax feederrefer to notes aboveSouth4 off counterpoiseradials each 33' 3" longProofread by G3YEUGraphics by G8ODE April 2011 iss 1.340m Compact 4-Square Antenna – EA5AVLEA5AVL Compact 4-Square 40m Antenna - CONTROL BOX CIRCUITSAntenna 1NorthAntenna 2EastAntenna 3SouthAntenna 4WestREMOTE RELAYSWITCH BOXoff1&2 RLA1&2 RLB1&2 RLCon1&2 RLDoffon500PFCOILCOILCOILCOILRLA /2RLB/2RLC /2RLD /2RG213 CoaxDC Control CableSelectAntenna 1SelectAntenna 2SelectAntenna 3SelectAntenna 4onCAPACITORBOXToTxerS1AS1BS2AS2BS3AS3BS4AS4BoffSWITCH BOXSelect NorthSelect EastSelect SouthSelect West_+DC 12v-13.8vPower SupplyNOTES1. Both contacts of all switches and relays are wired in parallel to improve reliability of operation.2. The relays are DPDT changeover with 12v coils, the clamping diodes are 1N1004 (100v 1A) and the capacitors are 0.1 MFD discceramic.3. Coaxial cables to the antennas are earthed at the relay switch box and are 1/4 wavelength long.4. The reflector tuning capacitor is an air-spaced variable from a domestic radio, 250+250 pF and both section are wired in parallel.5. The negative of the power supply is connected to the coax braid connected to the antenna relay box6 .All switches are heavy duty toggle switches. For correct operation only one antenna is selected , the other 3 act as reflectors7. The switches and relays are all shown in the OFF or non-operated positions. For correction operation of the antenna only operateone of the four switches to select the desired beam direction, the other three antennas Will behave like reflectors.Proofread by G3YEUGraphics by G8ODE April 2011 iss 1.32 [ Pobierz całość w formacie PDF ]

  • zanotowane.pl
  • doc.pisz.pl
  • pdf.pisz.pl
  • styleman.xlx.pl

    		•