登陆注册
19487500000015

第15章

"In 1965" George told me, "I was the only SV station equipped for contacts via meteor scatter so it was easy for me to make contacts with many European stations.The longest distance I achieved was withUA1DZ a Physics Professor at the University of Leningrad in the Soviet Union."Norman: "Forgive me for interrupting you, but please explain in simple terms what you mean by meteor scatter."George: "Meteor scatter is a way of making contacts on 2 metres by reflection from meteorites - `shooting stars' as they are called colloquially- which we see on clear nights during the summer.Of course they are not falling stars at all - they are meteorites which burn up when they hit the earth's atmosphere, leaving the trail that we see.We take advantage of this phenomenon for bouncing our signals off the trail but unfortunately it is a very short-lived event.Once when there were a lot of meteorites I was able to maintain contact with LX1SI of Luxembourg for a whole three minutes on SSB.It was during the period of the Persides which usually occur for a week in August when the earth's orbit takes it through this cloud of space debris.Millions of meteorites can be as small as a grain of sand and of course leave no visible trail when they strike the earth's atmosphere.The earth goes through other major clusters in April and in December.The phenomenon can also affect signals on lower frequencies.One can be in QSO on 20 metres via ground wave with a station a couple of hundred miles away with signals around s2 to s3.Suddenly one or two words are heard at s9 which indicates a momentary reflection off a meteorite trail."George also explained that in order to defeat the brevity of the time when communication was possible it was customary to record a message on a tape recorder and transmit it at high speed.The other station would also record at high speed and then play back at normal speed to hear the message normally.

I asked SV1AB to tell me about Sporadic E propagation.

"In this form of contact the signals are reflected from an ionised area 90 to 120 kilometres above the surface of the earth.I have been having contacts by this method for about 18 years now even before the advent of SSB on two metres.I have had contacts with England and with Moscow to the north-east of Athens.The phenomenon occurs for three or four months during the summer, and never during the winter.The ionisation movesvery rapidly sometimes - you may be talking to a station in Malta and he suddenly disappears and a station in Yugoslavia comes up on the same frequency.""Every summer" George continued, "we get Troposcatter which allows communication on all frequencies from VHF to 10 GHz even.This type of propagation occurs during certain special meteorological conditions, like high barometric pressure and extreme heat.We sometimes hear stations in Malta and Sicily with very loud signals.""In 1966 I built an aerial array consisting of 8 nine-element Yagis for 2 metres with the axis of rotation pointing to the North Star enabling me to track the Moon automatically.I was hoping to make some Moonbounce contacts, but at that time it was very difficult to construct low noise preamplifiers.After many days and hours of trying I managed a single brief contact with F8DO in France.Some time later I heard that Mike Staal K6MYC had heard me in California.

"The funny thing about this aerial array was that it enabled me to receive television signals from Nigeria on Channel 3 but only when I raised it up to an elevation of nearly 90 degrees."Norman: "I understand that Costas Georgiou SV1OE is the only Greek amateur who has had successful QSOs via Moonbounce."George: "Yes indeed.But it was many years later, using a low noise GASFET preamplifier.K1WHS in the U.S.A.has an array consisting of48 Yagis which enable him to contact stations with more modest installations.

同类推荐
  • 说呼全传

    说呼全传

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。
  • 明医杂着

    明医杂着

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。汇聚授权电子版权。
  • 枫窗小牍

    枫窗小牍

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。
  • 包氏喉证家宝

    包氏喉证家宝

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。
  • 阳曲傅先生事略

    阳曲傅先生事略

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。
热门推荐
  • 神话纵横

    神话纵横

    远古神话在这一刻复苏,当不同的神话交替在一起的时候,故事开始了主角是一个经历了阴暗职场后在家沉迷于ACG和历史神话的宅男,因为无意间收到了电脑上发现的奇异信号,好奇心驱使他去寻找真相,而就在那一天,他的生活被颠覆了,无数传说中的人物出现在了他面前。华夏封神,印度佛门,凯尔特神话,北欧神话,黄道十二星,希腊古神以及无数的英雄史诗,一一呈现在读者的面前。
  • 农门一品女御医

    农门一品女御医

    医科大学的高才生,古武世家的大小姐安如意,在毕业后被爷爷丢进了部队。历经千辛万苦,眼看着就要熬出头了,自由已经在向她招手,却不想在最后一个任务里阴沟里翻了船,不小心被流弹击中,翘辫子了。意外穿越重生在一个农家幼女身上,却是家徒四壁,父亲失踪,舅舅舅母欺负,还有泼皮无赖上门骚扰。看她整舅母,治无赖,施手段,扭转乾坤。机缘巧合重回父族,却又陷入一个又一个的阴谋中......
  • 20几岁学点博弈论(每天学一点时尚阅读书系列)

    20几岁学点博弈论(每天学一点时尚阅读书系列)

    《20几岁学点博弈论》内容简介:正所谓世事如棋,每个人在生活中都有棋逢对手的时候,也有兵败滑铁卢的瞬间,要想料事如神、见招拆招,就要看清楚棋盘上布的每一个子,能不能取得最后的胜利,就在于这每一步走得是不是正确、精彩,无论是在商场、官场,还是在职场,人们都会遇到形形色色的人,在生活中的大事小情中,也都会遇到不同的冲突和竞争,要想有所作为,就要有策略地思考问题,以理性的角度分析和筹划,预测对方的反应并采取合理的行动,以取得优势,创造对自己有利的结果,这就是《20几岁学点博弈论》要展示给读者的生存本领。
  • 雪袍鸿情

    雪袍鸿情

    在巫师、仙魔盛行的年代,谷岗国英俊的国王久闻莫桑草原上有一位世上最美丽的女子帕默尔。国王要娶其为妻。于是他派遣一支求婚大军前去求亲。大军在年轻的首领波尔泰将军和雪袍巫师的帅领下,途中一路艰难险阻。在洗魂谷有个世上最贵的旅店,且其内在格局每天都在变化着,时间和空间的交错感,让波尔泰及其一行人进入到谜团中。最终波尔泰与巫师历经磨难找到了美丽的帕默尔。然而帕默尔却爱上了一个让任何人意想不到的人,拒绝了国王的盛情。由此国王做出了最不可思议的决定改变了帕默尔的命运。
  • 魑魅魍魉之主

    魑魅魍魉之主

    九州云陆之上,登基新皇无能,群雄迸起,乱世之下,相传有一人立于巅峰,俯瞰天下,万人瞻仰。那人就是,魑魅魍魉之主,四少,月华夜。她女扮男装拼搏,他因爱在她身旁辅佐,待天下平定,再说情缘。
  • 新灵道

    新灵道

    这是一个新的时代,新灵元前两百年,九座灵庙从天而降,落在了地球的九个不同的国家,先驱者们从灵庙中带出了灵文和教导人类使用灵文的道印。经过一百年的发展,灵文和道印成为了在这片大陆上被人类广泛使用的新的力量,新的力量也被当做一种新的能源,运用于当今人类生活的各个层面。
  • 最强妖孽

    最强妖孽

    绝艳狐仙穿越现世,小记者偶得神秘手机系统,陈默的平凡人生从此平步青云。没钱花?我有【软妹币兑换器】!分分钟兑换大把红票子!想干架?我有【健身管家】!力拔千钧不在话下!【神奇相机】【心声探测器】各种牛叉app,有流量任我下载!没有解决不了的问题。
  • 愿生在那幻想乡

    愿生在那幻想乡

    一万个人的心中会有一万个幻想乡!PS:其实就是幻想乡的故事合集啦,每一卷主角,设定都会不一样。不过都是幻想里面发生的故事就是了。
  • 奇幻无穷

    奇幻无穷

    幻包含幻阵,幻术,幻法。亦存在一种变异之物,幻灵,战斗之灵,辅修之灵,生命之灵~每创一种幻,皆要领悟天地间的理!修至高强,画地为江河,摄土为山岳,嘘呼为寒暑,喷嗽为雨露。
  • 《命运的轮回线》

    《命运的轮回线》

    两条平行线终不会相交...十年前错过了,十年后亦是如此