{"id":1233,"date":"2015-06-01T20:17:53","date_gmt":"2015-06-01T20:17:53","guid":{"rendered":"http:\/\/www.tsgarc.uk\/?p=1233"},"modified":"2015-06-01T20:33:20","modified_gmt":"2015-06-01T20:33:20","slug":"the-hexbeam","status":"publish","type":"post","link":"https:\/\/www.tsgarc.uk\/?p=1233","title":{"rendered":"The Hexbeam"},"content":{"rendered":"

\"MW0JZE<\/a>Hi Andrew (G0RVM<\/a>) here… \u00a0I really enjoy working HF portable due to a home that’s in a noisy urban conurbation and the joy\u00a0of being out in the country, often with seriously impressive scenery all-around. \u00a0This post is about my recent purchase, a MW0JZE<\/a> constructed G3TXQ Hexbeam<\/a> antenna.<\/p>\n

Up to now I’ve been using\u00a0simple wire antenna’s such as monoband dipoles and delta loops strung over or between portable fibreglass telescopic masts when operating portable. \u00a0Due to the exceptionally low noise floors found at portable sites I can hear just about anything if its there, but\u00a0its difficult to get\u00a0heard due to the negligible gain of simple\u00a0antenna’s. \u00a0Enter the hexbeam, a 2-element Yagi for 6m, 10m, 12m, 15m, 17m and 20m giving useful forward gain (approx. 3 to 3.5dBd), a good\u00a0front to back ratio and deep side nulls that should\u00a0help during\u00a0crowded band conditions. \u00a0For example, a few years ago I planted a multi band vertical on the beach of a Scottish island. \u00a0Yes, the antenna worked well, but it was just impossible because of very strong signals from all directions. \u00a0Having some directivity and more importantly some useful nulls should greatly help.<\/p>\n

\"MW0JZE<\/a>Of course antenna\u00a0beam pattern is not everything when operating portable; other significant considerations are the collapsed size, weight & portability, the erected size and finally ease of assembly\/disassembly. \u00a0The hexbeam scores highly on all these characteristics. \u00a0Conscious that the Thornbury and South Gloucestershire Amateur Radio Club (TSGARC)<\/a>, my club, had a field weekend during May I decided to take the plunge and get a hexbeam in time for the event. \u00a0The TSGARC\u00a0as a 12m trailer tower so supporting the hex\u00a0would not be a problem.<\/p>\n

The hexbeam is\u00a0not a complicated antenna and quite frankly I could make one myself, however, I wanted more than a prototype antenna, I wanted something that would cope with the vagaries of the English climate and was robust. \u00a0i.e. it would stay\u00a0dry in a wet English climate and would withstand multiple rounds of assembly\/disassembly. \u00a0Importantly, I wanted something which when arriving at a portable location was dependable. \u00a0There are a few manufacturers of commercial hex beams and each seems to do a fixed and a portable variant. \u00a0The portable versions are lighter and designed to fold. \u00a0As my primary use was to be portable, a portable version seemed the right\u00a0choice… \u00a0However, I wanted something that was also robust and which could be erected full-time if I ever got\u00a0a property where that should be possible. \u00a0So I went for a fixed version!<\/p>\n

\"MW0JZE<\/a>After some\u00a0Internet research I opted for one constructed by Anthony (MW0JZE<\/a>) partly because of his\u00a0good website, partly because of the excellent Youtube construction video’s but also because when we spoke he was very helpful and had experience of portable operations.<\/p>\n

His\u00a0antenna arrived in a cardboard box, inside everything was wrapped, even double and triple wrapped in news paper. \u00a0Not quite what I expected and a real nuisance to unpack, but hey, you only unpack it once, the packing worked well and its eco-friendly – none of that plastic packing which is such a nightmare to dispose off \ud83d\ude42 \u00a0At home there is nowhere to assemble the antenna but I checked that the major components were present and just hoped the smaller bits and pieces (cable clips, nuts etc) were all present as I’d only find out for sure at the field event.<\/p>\n

I need not have worried as everything was present, Anthony had even included some extra ‘wing-nuts’ as he knew my intention was to use it portable. \u00a0So it was a warm, sunny Saturday when I constructed the antenna in a\u00a0large field with plenty of space. \u00a0From the outset I had a good feeling about the antenna as the build quality of the parts I’d seen at home was high. \u00a0The fiberglass spreader arms fitted together perfectly, the arms into the baseplate and the radius and diameter cords just dropped into place.\u00a0 Anthony had\u00a0obviously taken great care in its design and build.<\/p>\n

\"MW0JZE<\/a>As mentioned before, assembly was done in a field so it was a little disappointing that there were no hardcopy assembly instructions. \u00a0 Fortunately I had good Internet access via a\u00a0TSGARC<\/a> members cellphone and thus I could watch the assembly YouTube instructions. \u00a0What would be really nice is if Anthony could supply the videos on a CD or include some instructions. \u00a0Had Internet access\u00a0not been possible,\u00a0I’m confident I’d have worked it out, but having the\u00a0reassurance was nice.<\/p>\n

\"MW0JZE<\/a>The antenna has a sexy blue engraved baseplate with\u00a0‘G3TXQ’ and a diagram of a hexbeam. \u00a0It also has a large arrow with no associated text… \u00a0 I constructed the antenna as per the video’s (which didn’t show the arrow) but in haste I assumed the arrow indicated the forward direction of the antenna and thus mounted it to the tower so that the arrow pointed North. \u00a0Wrong. \u00a0If constructed as in the video’s the arrow points towards the back of the antenna\u00a0\ud83d\ude09 \u00a0Anyway, it was terribly easy to fix. \u00a0Just a 180 degree rotation of the stub mast that fixed the rotor to the tower. \u00a0This change took about 5 mins and that included lowering and raising the tower!<\/p>\n

I purchased the toroidal choke balun with the antenna and this fixed to the centre post\u00a0with a plastic clamp. \u00a0There was a minor misalignment of its\u00a0fixing holes but nothing a\u00a0very slight enlargement of the fixing holes didn’t sort. \u00a0On air, the antenna performed as expected; it demonstrated reasonable f\/b ratio and good nulls to the sides. \u00a0It was fed with around 400w and we received good reports from countries such as Japan, Argentina, Aruba, the USA, St. Helena Is to mention\u00a0a few. \u00a0So it worked and better than a wire dipole would have done I’m sure \ud83d\ude09 \u00a0Perhaps next time I’ll do some side-by-side tests.<\/p>\n

\"MW0JZE<\/a>I pondered for some time the best way to dismantle the antenna at the end of the field event. \u00a0I didn’t want to completely dismantle the antenna but only dismantle sufficiently to allow it to be packed and transported. \u00a0It was actually a simpler problem than I had first thought. \u00a0The element wires were disconnected from the centre post; the radius and diameter cords were disconnected; the spreader arms were disconnected from the base plate, the spreader arms were disconnected from each other and placed next to each other then finally all spreader arm parts were brought together in a neat pile. Finally the mass of spreader arms and element wires were dropped into a bag. \u00a0The baseplate was left attached to the centre post. \u00a0Next time it should be just a matter of getting it out the bag and reversing the process described above… \u00a0Time will tell. \ud83d\ude42<\/p>\n

A good strong\u00a0bag, something about 170cm long and 60cm in diameter with carry handles and compression straps would be an excellent addition \ud83d\ude42<\/p>\n

Thanks for the antenna Anthony<\/a>, I’m really looking forward to using it\u00a0again and perhaps performing a more scientific comparison with another antennas.<\/p>\n

Andrew<\/em>
\n G0RVM<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Hi Andrew (G0RVM) here… \u00a0I really enjoy working HF portable due to a home that’s in a noisy urban conurbation and the joy\u00a0of being out in the country, often with seriously impressive scenery all-around. \u00a0This post is about my recent … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[5],"tags":[9,17,113,27],"class_list":["post-1233","post","type-post","status-publish","format-standard","hentry","category-news","tag-antenna","tag-g0rvm","tag-hexbeam","tag-tsgarc"],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=\/wp\/v2\/posts\/1233","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1233"}],"version-history":[{"count":23,"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=\/wp\/v2\/posts\/1233\/revisions"}],"predecessor-version":[{"id":1290,"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=\/wp\/v2\/posts\/1233\/revisions\/1290"}],"wp:attachment":[{"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1233"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1233"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tsgarc.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1233"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}