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73 Dipole and Long-Wire Antennas

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73 Dipole and Long-Wire Antennas 73 Dipole and Long-Wire Antennas by Edward M. Noll, W3FQJ <~~?IND. ~!,~~.:~I ANAPOLIS.,"~ IND~~~!~~EI ANA 46268,~~ FIRST EDITION THIRD PRINTING- 1975 Copyright © 1969 hy Editors and Engineers, Ltd., New .-\ 111rnsta, Indiana. Printed in the Unite d States of America. :\II rights r<'Sl' rvl'd. He production or u se, without express pcrmission, of f'ditorial or pil'!orial content, in any manner, i' prohiliited. :"lo pat•' nt liahility is assumed with respect lo thf' use of the' information contained herein. Lihrary of Con j! r rss Cata loj! Card N umber: 72-81301 .. Preface An often-heard comment of the prei;ent is : " The (l ays of amateurs building an d o perating their own equipm ent arc a th in ~ of the past." To a great extent this is tr ue, since the advent of sophisticated single-sideband erJ11ipm ent h as convinced m any hams that construction of their own gear is no longer practical. The one big exception lo this approach to am ateur radio is in the fi elcl of antennas. T he ama teur, at very little ex p e n ~e ancl with· out the re(p1irement of an R and D laborator y, can indulge in experimentation an d build in!! an tcnnas- sometimes with startling rcsu lts. 'i."J Dipole and Long-Win' A nte1111as is the fi rst of a series of books which can make the h obby of amateur radio m ore than an operational spectator activity. Each antenna described in this book was con ~ trn c te d by the author, without assistance, and a m inimum of tools and equipment was use(!. You can do the sam e, a nd use the world as your testing 1"roun1l. Many of the antennas described in this book compete with, and someti mes surpass, the performance of commercial beams. A nnm· he r of new approaches in the construction of the basic long-wi re antenna types are detailed. There are 73 individual antennas included in an order that b C' ~ in s with simple construction and prol!re~ses in a sequential m anner to more complex ar ran ~e me nt s . However, if you are in­ te rested in only on e particul ar type, you can locate that type im­ m ediately, and fi nd t h at each type is completely described. 7:1 Dipufo and Long-Wir<' A ntennas is an invitation to some in­ expensive education and fun. You will find it ve l" y educational and satisfyin l! to put u p a cheap antenna that yon have calculated, e rected, and tuned . You a lso gain a fringe benefit- that in talking to amateur friends all over the world, YOU can describe your an­ tenna setup and really know what you ~re talking about.. EDWARD M. NoLL, W:>FQJ • Contents SECTION 1. REGULAR AND MODIFIED DIPOLE ANTENNAS 1. Half-Wavelength Dipole......................... ............................... 9 2. Dipole Antenna, Line Tuned ................................... ............. 11 3. Dipole and Balun ...................................................................... 14 4. NoYice-Band Dipoles ......... ................... ····················-···-····-····· 15 5. Aclvancecl and Extra-Class Band Dipoles ............................ 16 6. Lamp-Cord Dipoles ................................................................. 16 7. Twin-Lead Folded Dipole ................... ········ ············--··-········· 18 8. Folded Dipole and Balun ................................................... 18 9. Inverted Dipole ............... ....................... .................................. 19 10. rovice 15-40 Dipolt>s ................................................. ................. 21 11. ~o,· ice 15-80 Dipoles ......................... ................................. 23 12. :\'"oYice 40-80 Dipoles ................................................................ 23 13. Novice 15-40-80 Dipoles ................. ......................................... 24 14. 20-40-80 :Vlaypole ...................................................................... 26 15. 20-40-80 C-W Special ........................ ...................................... 28 16. One-W avelenl!th Antenna . ..................................................... 28 17. 3/2-Wavelenl!th Antenna ........................................................ 30 18. Low-Band Segmented Dipoles, 40-80-1 60 .............................. 33 19. Middle-Band Sc1tmcn ted Dipoles, 20-40-80 .......................... 34 20. Open-Wire Two-Band Dipole ......... .. ..................................... 35 21. Extra and Advanced Open-Wire Inverted Dipoles ....... ..... :n SECTION 2. INVERTED-VEE ANTENNAS 22. Center-Fed Monoband Inverted Lon:r-Wire Vees .......... ...... 41 23. Two-Band Inverted Long-Wire Vees- No Tuning ............ .. 43 24. Two-Band lnvertc«l Vee-End Tuned ................................. 44 25. Lon:r-Wire Inve rted Vee- Sideband 10-15-20 ......... .. ......... 46 26. All-Band 6-160 inverted Vee ................................................ 47 27. 15-40 Novice Inverted Vee ................. ............................ ....... 49 28. 15-40-80 Novice Inverted Vee .......................... .. ................... 50 29. 10-15-20 and 20-40-80 lnverte1l-Vee Trio ........... .................. 52 30. W3FQJ Inverted-Vee 6-Through-80 Sidebander ................ 52 31. Long-Wire Inverted Vees With Line Tuner ........................ 55 SECTION 3. LONG-Wl1RE ANTENNAS 32. Single Long-Wire Resonant Antennas-Center Fed ............ 59 33. Single End-Fed Monoband Long-Wire Resonant Antennas .................................. .......................................... ....... 61 34. 10-15-20-40 Long-Wire WAS Special .................................... 63 35. Single Random Wire With Line Tuner ................................ 65 36. Resonant Antenna Plus Random-Wire Loading ................ 66 SECTION 4. VEE-BEAM ANTENNAS 37. End-Fed Monoband Inverted-Vee Beam .............................. 71 38. IO-, 15-, and 20-Meter Inverted-Vee Beam .......................... 73 39. Four-Band Inverted-Vee Beam With Tuner .. ... ................... 75 40. Three-Halves Wavelength Horizontal Vee .......................... 76 41. 15-40 Three-Halves-Wavelength Vee .................................... 78 42. 15-40 Conical Three-Halves-Wavelength Vee ...................... 79 43. 15-40 Conical Vee With Balun ............................................. 80 44. Short Horizontal Vee-Beam Antenna .................................. 81 45. Duo-Band Horizontal Short Vee Beams .............................. 82 46. Tilted Short Vee Beams .. .................................... .................... 83 47. 10-15-20 Short Vee Beam ........................................................ 84 48. 10-15-20-40 One-Hundred Footer .......................................... 85 49. 10-15-20-40 Short Vee Beam .................................................. 87 50. 10-15-20-40-80 Vee Beam and Inverted Dipole ..... .............. 88 SECTION 5. LONG VEE-BEAM ANTENNAS 51. Long Horizontal Vee-Beam Antenna .................................... 93 52. Long Horizontal Vee-Beam Antenna, Two Bander ... ......... 96 53. 10-15-20 Vee Beam \Vith Li11e Tuner ................. .................. 98 54. Muhiband Vee-Beam Antenna With Antenna Tuner ........ 98 55. Sloping Vee Beam ............................. ....................................... 100 56. 10-15-20 Sloping Vee Beam ....... ............................................. 101 SECTION 6. RHOMBIC ANTENNAS 57. 10-15 Rhombic Antenna .........................................................107 58. 10-15-20 Rhombic With Line Tuner ...................................... lll 59. 10-15-20-40 End-Tuned Rhombic ...... ..................................... .113 60. Two-Wire 10-15-20 Rhombic .................................................. 114 61. Resonant Rhombic With Tuner and Open-Wire Line ........ 115 62. Terminated Rhombic ................................. ................ ............ .116 SECTION 7. VERY LONG LONG-WIRE ANTENNAS 63. Two-Band Very Long Long-Wire Antenna .......................... 121 64. Eno-Tuned Very Long 5 DXCC Lon~ Wire ........................ 123 65. 5 DXCC Lonf!-Wire Special .................................................... 125 66. All-Band 6-160 End-Fed Very Lonr; Wire With Tuner .... 126 67 . Long-Path Short-Path Long-Wire Antenna .......................... 128 SECTION 8. SPECIAL VEES AND RHOMBICS 68. 160-:.Vleter Two-Mas t Inverted Vee ........................................ 131 69. 10-1 60 End-Tuned Two-1\last Inverted Vee .......................... 132 70. Two-\Ta st Vee Beam ................................................................ 133 71. Three- and Four-1\Iast Switchable Vee Beams .................... 134 7'2. Tw o- :.\ r a~t Rhombic .................................. ..... ...........................1 37 73. Short Squared Rhombic .......................................................... 138 APPENDIX I Antenna ::\'oise Bridge .................................................................... 143 APPENDIX II How to :\feasure the Yclocily Factor of Transmission Line \'\'ith a Noise Bridge ........................................................1 45 APPENDIX III Cuttinf! Half.,Vave Sections of Transmission Line Using the A11 tcnna Noise Bridge ............................................ 147 APPENDIX IV :vreasurin::r the Resonant Frequency and Hesistance of an Antenna With the Antenna Noise Bridge .................. 149 APPENDIX V Cutting an Antenna to Resonance Usin µ: an SWR Meter ..... .. .1 52 APPENDIX VI T he Construction and Tuninµ: of a Line Tuner ........................ 154 APPENDIX VII Antenna Tuner for Lonµ:-W ire Vees a!Hl Hhombics .................. 159 SECTION I Regular and Modified Dipole Antennas
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