{"id":1007,"date":"2020-11-15T09:27:20","date_gmt":"2020-11-14T23:27:20","guid":{"rendered":"http:\/\/www.crest.org.au\/wordpress\/?p=1007"},"modified":"2020-11-15T09:31:22","modified_gmt":"2020-11-14T23:31:22","slug":"raffetys-coastal-run-2019","status":"publish","type":"post","link":"https:\/\/www.crest.org.au\/wordpress\/?p=1007","title":{"rendered":"Raffety\u2019s Coastal Run 2019"},"content":{"rendered":"\n

\nOn Saturday 18 July, 2019 CREST NSW Inc set up a radio network for\nthis event, as we have done for quite a number of years now.<\/p>\n\n\n\n

The event takes in the views of Lake\nMacquarie, Catherine Hill Bay and the Munmorah State Recreation area.\n There are three route options for the competitors \u2013 12, 22 and\n36km.<\/p>\n\n\n\n

For this event, the norm is to set\nup a main or \u201chub\u201d repeater site covering the northern end along\nwith a secondary linked repeater site covering the south. VHF\nMidband is used for the system backbone with all network users on\nUHF.<\/p>\n\n\n\n

As a test, we also setup a\n\u201cultra-portable\u201d cross-band system utilising a couple of portable\nradios. The idea of this is that it can be deployed into locations\nthat are strictly walk in either due to land owner policy or terrain\nlogistics. In these applications, the novelty of carrying generators\nover distance can wear off very quickly. In addition, the ability to\nkeep batteries charged using solar can also be challenging due to\nvegetation tree canopies with very limited results.<\/p>\n\n\n\n

In this experiment, the mast was not that portable but it did not have to be. It was a 50m walk from the vehicle to the selected site. It was however somewhat windy that day so the more robust must was considered more appropriate.<\/p>\n\n\n\n

\"\"
Portable mast around 6m high with VHF Midband Ground Plane and UHF Side Mounted Dipole antennas. <\/figcaption><\/figure>\n\n\n\n

The cross-band radio repeater\nconsisted of a Kenwood TK3107 UHF portable and an Icom IC-F30G\noperating in VHF Midband, connected via a Surecom SR-629 repeater\ncontroller. \n<\/p>\n\n\n\n

A consideration of this type of\nconfiguration is that we should be very considerate of attenuation in\ncoaxial cables and connectors in order to get the most out of that 5\nWatts. Belden 9913 Coaxial cable which conforms to a RG-8\nspecification was used on UHF. We should have probably used the same\nfor the VHF midband but on the day, rather lax with RG-58C\/U. We\nwere probably only delivering about 2.5W of VHF Midband RF into the\nantenna and while that seemed to work fine, we must give ourselves\nthe option in the near future of a VHF groundplane antenna that is\nterminated with an N Connector.<\/p>\n\n\n\n

Power comes from the individual\nradio battery packs themself. The above two radios are used because\nthere are lithium-ion battery pack options available. This system\nwas given a pretty fair work out and the lithium-ion pack on the UHF\nwas down to one bar after four hours. The VHF Midband spending the\nvast majority of its time on standby\/Receive was still full at the\nend of the job. The duty cycle experienced on the event did not\nappear to be an issue.<\/p>\n\n\n\n

In conclusion, not a bad option\nwhere we cannot use \u201cnormal\u201d repeater base station equipment for\ntemporary or emergency jobs. You would be surprised what you can do\nwith 5 Watts of RF.<\/p>\n","protected":false},"excerpt":{"rendered":"

On Saturday 18 July, 2019 CREST NSW Inc set up a radio network for this event, as we have done for quite a number of years now. The event takes […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-1007","post","type-post","status-publish","format-standard","hentry","category-recent-operations"],"_links":{"self":[{"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/1007","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1007"}],"version-history":[{"count":2,"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/1007\/revisions"}],"predecessor-version":[{"id":1010,"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/1007\/revisions\/1010"}],"wp:attachment":[{"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1007"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1007"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.crest.org.au\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1007"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}