{"id":341,"date":"2016-04-14T23:54:34","date_gmt":"2016-04-14T21:54:34","guid":{"rendered":"http:\/\/www.ik0vve.net\/?p=341"},"modified":"2016-05-12T20:39:23","modified_gmt":"2016-05-12T18:39:23","slug":"the-630m-antenna","status":"publish","type":"post","link":"https:\/\/www.ik0vve.net\/?p=341","title":{"rendered":"The 630m antenna"},"content":{"rendered":"

In the last weeks I’ve tested a new antenna for 630m band. To have also something usefull for 2200m I’ve built an helical loaded vertical antenna followed by a 3-wires hat, so to have a longer radiator that resonate about on 350 KHz.<\/p>\n

\"100_4336\"<\/a><\/p>\n

The coil was about a 45 meter long 3 cm aluminium tape with a thickness of 0.3 mm. It was distributed along a 10 meter high fiber pole (used for my old 80m inv-L antenna).
\nAfter\u00a0windings all the turns I’ve fixed\u00a0the vertical “python” in the final position and tried to\u00a0stretch the hat wires… after some seconds I heard “crackkkk”… one of the tubes cracked for the strong flexure.<\/p>\n

So, the antenna down again, tube repaired with\u00a0resin-soaked bandage but now I’ve used a second telescopic tube to support the hat.<\/p>\n

Very good! To tune\u00a0the antenna on 475 KHz I’ve inserted a 1200 pF variable vacuum capacitor, it was too long. Tried the antenna for a few\u00a0days, as long as a in a weak\u00a0windy day I made this photo:<\/p>\n

\"100_4337\"<\/a>
\nThere was something strange, the twists were too close and the bending was too evident! Again the antenna down on the roof. One of the inner poles was broken!<\/p>\n

So why don’t use the telescopic pole as new antenna? It’s a 10m high pole, and I don’t need of the big coil for 630m. So I’ve decided to use the steel pole and\u00a0with the only variometer I found the perfect tune on the 630m band!
\nHere it is:\"100_4342\"<\/a>\u00a0…and here the full 10 meter long hat.\"100_4341\"<\/a><\/p>\n

The next step will be to fatten the vertical pole to increase performance and probably to\u00a0strengthen the ties.<\/p>\n

So if you at the moment hear my signal it comes out from this thing, an inv-L 10\u00d710 meters about.<\/p>\n","protected":false},"excerpt":{"rendered":"

In the last weeks I’ve tested a new antenna for<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[5,13,3,6,7,53],"tags":[],"_links":{"self":[{"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=\/wp\/v2\/posts\/341"}],"collection":[{"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=341"}],"version-history":[{"count":8,"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=\/wp\/v2\/posts\/341\/revisions"}],"predecessor-version":[{"id":461,"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=\/wp\/v2\/posts\/341\/revisions\/461"}],"wp:attachment":[{"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=341"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=341"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ik0vve.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=341"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}