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<\/figure>\n\n\n\nLes brins rayonnants sont soud\u00e9s sur un morceau de circuit imprim\u00e9 qui sert d’isolateur et est suffisamment r\u00e9sistant \u00e0 la traction. Les brins rayonnants \u00ab\u00a0de gauche\u00a0\u00bb de chaque doublet sont tous connect\u00e9s ensemble et reli\u00e9s \u00e0 l’\u00e2me du c\u00e2ble coaxial tandis que les brins \u00ab\u00a0de droite\u00a0\u00bb sont r\u00e9unis \u00e0 la gaine du c\u00e2ble (ou vice-versa !). Pour faire de la r\u00e9ception ces dimensions suffisent, pour passer en \u00e9mission, il convient de tailler les brins un peu plus long et d\u2019ajuster avec TOS m\u00e8tres.<\/p>\n\n\n\n Les brins sont en c\u00e2ble \u00e9lectrique de 2.5 mm, des entretoises en PVC conservent l’\u00e9cartement, les drisses sont des cordes \u00e0 linge Juste un aper\u00e7u des premiers contacts r\u00e9alis\u00e9s lors des tests de l’antenne.<\/p>\n\n\n\n Je voulais construire une antenne \u00e9mission\/r\u00e9ception simple pour couvrir plusieurs bandes radioamateur en HF.J’ai choisi le 40 m\u00e8tres 7MHz pour<\/p>\n","protected":false},"author":4,"featured_media":647,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[11,21,14],"tags":[],"class_list":["post-644","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-activites-radio","category-antenne","category-realisations"],"_links":{"self":[{"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/posts\/644","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/comments?post=644"}],"version-history":[{"count":1,"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/posts\/644\/revisions"}],"predecessor-version":[{"id":650,"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/posts\/644\/revisions\/650"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/media\/647"}],"wp:attachment":[{"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/media?parent=644"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/categories?post=644"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/f6kmf.fr\/index.php\/wp-json\/wp\/v2\/tags?post=644"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
On utilise la formule habituelle pour d\u00e9grossir chacun des dip\u00f4les :
Lphys = 143\/f avec f en MHz.
Donc :
143 \/ 7 = 20,42 m chaque c\u00f4t\u00e9 mesurera 10,21 m<\/strong>
143 \/ 10 = 14.43 m chaque c\u00f4t\u00e9 mesurera 7.15 m<\/strong>
143 \/ 14 = 10.21 m chaque c\u00f4t\u00e9 mesurera 5.10 m<\/strong>
L’alimentation se fait en c\u00e2ble coaxial 75 ohms<\/p>\n\n\n\n![\"\"](\"https:\/\/f6kmf.fr\/wp-content\/uploads\/2020\/06\/IMG_20200525_152216-1024x768.jpg\")
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en nylon. <\/p>\n\n\n\n![\"\"](\"https:\/\/f6kmf.fr\/wp-content\/uploads\/2020\/06\/IMG_20200529_211000-1024x768.jpg\")
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