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GET /hyperkitty/api/list/[email protected]/email/JAOGDDGJ7PZ4QN266FDYWBJB76JRRMS5/?format=api
{ "url": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/JAOGDDGJ7PZ4QN266FDYWBJB76JRRMS5/?format=api", "mailinglist": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/?format=api", "message_id": "D688B24E7E6E404AB5263D57657C2158@kc6uqh", "message_id_hash": "JAOGDDGJ7PZ4QN266FDYWBJB76JRRMS5", "thread": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/thread/NBO5E534X55E6BSQWUF2SKFBCZTXHRKV/?format=api", "sender": { "address": "kc6uqh (a) cox.net", "mailman_id": "d9201820d18047e4a2772c86bda5e111", "emails": "https://mailman.amsat.org/hyperkitty/api/sender/d9201820d18047e4a2772c86bda5e111/emails/?format=api" }, "sender_name": "Art McBride", "subject": "[amsat-bb] Re: Mode S advice", "date": "2008-10-05T05:04:35Z", "parent": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/NBO5E534X55E6BSQWUF2SKFBCZTXHRKV/?format=api", "children": [], "votes": { "likes": 0, "dislikes": 0, "status": "neutral" }, "content": "Michael,\nI would recommend a small 18\" Dish with a patch or 3 turn helix feed.\nHelixes at 2.4 are somewhat tricky and long helixes are effected by the\nplastic used to hold the turns. Self supporting helixes are difficult to\nmake beyond 3-4 turns. Feed should be opposite rotation however I recall\nAO-51 is linear polarization on 2.4 GHz.\n\nArt\n\n-----Original Message-----\nFrom: [email protected] [mailto:[email protected]] On\nBehalf Of Michael Heim\nSent: Saturday, October 04, 2008 4:08 PM\nTo: [email protected]\nSubject: [amsat-bb] Mode S advice\n\nLast month I was experimenting with mode S receive antennas, and I think I\nposted some questions on here as to what you guys who are on mode S use.\nAlthough I have operated microwave, I have never done so via the satellites.\n\n\nI have 2 options and both appear to work about equally. one involves a\nlinear yagi, the other a helix, RHCP. The last time the bird was in mode S\nanalog, it used mode L for the uplink. I noticed, while listening in using\neither antenna, a noticeable amount of deep fades on the bird. I'm not sure\nif it was caused by reflections nearby, or uplink fades on 1269 mhz. Both\nof these antennas were mounted on a camera tripod about 4 feet off the\nground, and there was some metal within about 25 feet or so, which is\nunavoidable. The antennas will be placed about 15 feet above the ground,\nand the metal in the vicinity will be below the antenna.\n\nSo, your advice... should I go with a 16 dbi linear yagi, commercially made\nfor the MMTS band, or the RHCP homebrew 12 turn helix? I am having trouble\ngetting much longer than 12 turns, winding the helix evenly. Is there\nreally an advantage in using either? I guess I'm looking for whatever will\ndo the best as far as fading goes. I am impressed, as the signals were\nquite strong while using only 2 foot long antennas.\n\nBy the way, I am building a 1269 TX converter from scratch. I happened upon\na brick oscillator that I recrystalled for the proper LO for a 144 IF. The\nmode S IF is 123 mhz, so there should be no IF leakage problems.\n\n Michael Heim\nChief Engineer, Forever Broadcasting\nNew Castle PA\nWKST WJST WWGY\n814-671-0666\nChapter Chair, SBE-122\nARS KD0AR\n_______________________________________________\nSent via [email protected]. Opinions expressed are those of the author.\nNot an AMSAT-NA member? Join now to support the amateur satellite program!\nSubscription settings: http://amsat.org/mailman/listinfo/amsat-bb\n\n__________ Information from ESET NOD32 Antivirus, version of virus signature\ndatabase 3495 (20081004) __________\n\nThe message was checked by ESET NOD32 Antivirus.\n\nhttp://www.eset.com\n\n \n\n__________ Information from ESET NOD32 Antivirus, version of virus signature\ndatabase 3495 (20081004) __________\n\nThe message was checked by ESET NOD32 Antivirus.\n\nhttp://www.eset.com\n \n\n", "attachments": [] }