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Любительская радиосвязь
milstar: Любительская служба: служба радиосвязи для целей самообучения, переговорной связи и технических исследований, осуществляемая любителями, то есть лицами, имеющими на это должное разрешение и занимающимися радиотехникой исключительно из личного интереса и без извлечения материальной выгоды — Регламент радиосвязи. Статьи. Том 1. Издание 2012 года. Международный союз электросвязи. Статья 1.56 ############ Известные радиолюбители-коротковолновики король Марокко Хасан II (CN8MH); король Испании Филипп VI (EF0F), его предшественник Хуан Карлос I (EA0JC) и сестра Хуана Карлоса I Маргарита де Бурбон-и-Бурбон (EA4AOR); короли Саудовской Аравии Сауд (HZ1SS), Фейсал (HZ1AF) и Фахд (HZ1AA); король Иордании Хуссейн I (JY1); король Таиланда Пхумипон Адульядет (HS1A); султан Омана Кабус бен Саид (A41AA); президент Аргентины Карлос Менем (LU1SM); президент Чили Аугусто Пиночет (XQ3GP); президент Италии Франческо Коссига (I0FCG); президент Ливана Эмиль Лахуд (OD5LE); президент Никарагуа Анастасио Сомоса (YN1AS); премьер-министр Индии Раджив Ганди (VU2RG) и его вдова Соня Ганди (VU2SON); премьер-министр Японии Кэйдзо Обути (JI1KIT); генеральный секретарь ООН У Тан (XZ2TH); физик, Нобелевский лауреат Джозеф Тейлор-мл. (K1JT, ex: KN2ITP, K2ITP); Макс Клаузен — радист советской нелегальной разведсети в Китае и Японии, соратник Рихарда Зорге[37]; создатель компьютера «Atari» Нолан Бушнелл (W7DUK); путешественник и исследователь Дмитрий Шпаро (UA3AJH); путешественник, диакон Фёдор Конюхов (R0FK); путешественник Наоми Уэмура (JG1QFW); командующий стратегической авиацией США генерал Кёртис ЛеМей (W6EZV); польский священник святой Максимиллиан Кольбе (SP3RN); участник ядерной бомбардировки Хиросимы Пол Тиббетс (K4ZVZ); сенатор США Барри Голдуотер (K7UGA); киноактер Марлон Брандо (FO5GJ, WA6RBU, KE6PZH, FO0MB, FO5BW, FO5HG); поп-певец Гарри Уэбб — Клифф Ричард (W2JOF); рок-музыкант, участник группы Eagles Джо Уолш (WB6ACU)[38]; футболист Сергей Ребров (UT5UDX, 5B4AMM); изобретатель метода магнитной стереофонической записи звука в кино Баз Ривс (K2GL)[39]; путешественник-яхтсмен Николай Литау (R3AL/mm); инженер, один из основателей компании Apple Стив Возняк (WA6BND / WV6VLY); Масару Ибука (J3BB) и Акио Морита (JP1DPJ), соучредители компании Sony; Присцилла Пресли, актриса и предприниматель, жена Элвиса Пресли (NY6YOS); миллиардер Говард Хьюз (W5CY). ################################ 28October 2002By Al Ward, W5LUA, and Barry Malowanchuk, VE4MA Moonbounce or EME (Earth- Moon-Earth) has always been our ultimate goal for each of the VHF and microwave amateur bands. The Journey to EME on 24 GHz http://www.arrl.org/files/file/Technology/tis/info/pdf/0210028.pdf 3 cm (10,000-10,500 MHz)The 3 cm amateur band is the most popular of the upper microwave EME bands. With today’s PHEMT technology providing 1 dB noise figures, the system noise floor is controlled more by the level of Moon noise received than the noise floor of the receiver. It is not uncommon to achieve between 1 and 2.5 dB Moon noise from 3- and 4-meter dishes at 10 GHz. The reception of Moon noise is possible because of the relatively narrow beamwidth of the dish at 10 GHz versus the subtended angle of the Moon. The sub-tended angle of the Moon is described as the apparent width of the Moon in degrees as seen from Earth. Since the beamwidth of the 3 meter dish at 10 GHz (0.7 degree) is nearly as small as the subtended angle of the Moon (about 0.5 degree), most of the noise that the antenna sees is gener-ated by the Moon, which is significantly hotter than the background cold sky. The Moon noise can also be used as an effec-tive means of keeping the dish on the Moon. Maximum Moon noise indicates the dish is optimized on the Moon. A 3 meter dish coupled with a 20 W TWT and a 1 dB noise figure provides a very nice 3 cm EME station that is capable of working several dozen stations. Since the first EME QSO on 3 cm by WA5VJB and WA7CJO in 1988, upwards of 50 stations in nearly 20 countries are currently op-erational on 3 cm EME. The smallest sta-tion W5LUA has worked to date is Dave, N4MW. Dave runs a 2.4-meter offset fed dish and 8 W at the feed. ---------------------------------------------------------------- 1.25 cm (24,000-24,250 MHz)The next higher amateur band at 24 GHz presents an even bigger techni-cal challenge. Parabolic reflectors quite often have very limited performance above 14 GHz due to surface inaccura-cies. Low noise amplifiers are not nearly as easy to make as can be done on 10 GHz. High power is very hard to come by. Part 2 of this series will address how VE4MA and W5LUA overcame these difficulties in order to make the first ever EME QSO on 24 GHz. ------------- EME эхо в диапазоне 47ГГц Версия в формате PDF Версия для печати Автор Сергей Жутяев, RW3BP Четверг, 29 Июль 2004 24-го июля 2004 г. удалось получить первое эхо, отраженное от Луны в диапазоне 47 ГГц. Это первое радиолюбительское эхо в диапазоне миллиметровых волн и первый диапазон, "распечатанный" для EME нашей страной. Сигналы были довольно слабые, но легко читаемые на экране монитора с помощью прграммы Spectran. Конечно это только первый шаг и придется приложить еще немало усилий для проведения первой двухсторонней радиосвязи. Диапазон очень сложный. В отличие от диапазона 24 ГГц, где основные потери в атмосфере связаны с поглощением молекулами воды здесь преобладают потери, вызванные молекулами кислорода. Если на 24 ГГц можно подождать сухую морозную зимнюю ночь, то здесь ждать особенно нечего. Кислород на наше счастье есть всегда. Конечно и на 47 ГГц вода поглощает и сухая погода не помешает. В этом смысле условия 24 июля были далеко не лучшие. Температура 24 градуса при 90 процентной влажности. Да и луна была на высоте всего около 20 градусов даже в своей высшей точке. То есть приходилось преодолевать значительную толщу атмосферы.Сигналы были "аврорного" типа, шириной около 300 Гц. Аппаратура: антенна параболическая оффсетная, диаметром 2,4м. коэффициент шума приемника 4,5 дБ. передатчик на ЛБВ. Как всегда огромную помощь в подготовке эксперимента оказал В. Прокофьев RA3ACE. Сергей RW3BP ################ RW3BP EME test on 77.5 GHz https://www.youtube.com/watch?v=2En_W2EaJFw https://www.youtube.com/watch?v=XoBB9AV7pWQ ################ https://www.youtube.com/watch?v=XBEgD4evOKM WR 10GHz EME A new 10-GHz Earth-Moon-Earth (EME or moon bounce) world record has been set. On September 9, Rex Moncur, VK7MO, and Jim Malone, WA3LBI, completed a 18,949.4-kilometer contact using QRA64D. VK7MO ran 50 W to a 1.13-meter dish using linear polarization. WA3LBI ran about 125 W to a 2.4-meter dish, RKI feed by Bert Moderman, circular polarization, mounted on a trailer. The loss in going from linear to circular polarization was somewhat less than the expected 3 dB, due to depolarization at the Moon surface (probably around 2 dB). The time was chosen to maximize the Moon window when spreading was low at 34 Hz and lunar degradation low at 0.8 dB. WA3LBI was first decoded at –23 dB at 1317 UTC when ground noise would be an issue, as the Moon was at 0° and only partially visible. His signal later peaked at –19 dB, when the elevation was around 2° at VK7MO. In addition to the basic contact requirements, some text messages celebrating the record were also exchanged. Afterward, VK7MO worked Al Ward, W5LUA, with strong signals up to –14 dB, followed by a second contact with WA3LBI, whose signal peaked at –17 dB and dropped to –23 dB at 1353 when WA3LBI lost the Moon.
Ответов - 14
milstar: https://www.icomamerica.com/en/products/amateur/receivers/r8600/Icom-R8600-QST-product-Review.pdf QST®– Devoted entirely to Amateur Radio www.arrl.org Reprinted with permission from November 2017 QSTTechnicalby Mark Spencer, WA8SMEIcom IC-R8600 Communications ReceiverA high-performance broadband receiver, with SDR versatility.Product ReviewMark J. Wilson, K1RO, k1ro@arrl.orgBottom LineCovering 10 kHz through 3 GHz and demodulating many popular analog and digital modes, the IC-R8600 can be used as a high-quality ham band receiver, or for lis-tening to many other radio services. Its dynamic performance rivals top-tier amateur transceivers. https://www.ab4oj.com/icom/r8600/main.html https://www.youtube.com/watch?v=xBhXP7Oznp0
milstar: программное радио с аналого-цифровым конвертером 16 bit AD9467 (SiGe approx 120$) Flex6700 https://www.flexradio.com/flex-6700/ https://www.flexradio.com/comparison/ ogranichenija po сравнению с гибридом Icom 8600 -тройной супергетеродин до 3 ghz и программное радио до 30 mhz для достижения высокого динамического диапазона необходимо использовать 16 битный конвертер с частотой выборки в 4 раза (практика NASA) больше высшей частоты на входе AD9467 250 msps /Flex6700 =62.5 mhz в обозримом будущем прогресс в 16 битных АЦП не предвидится,и двойной тройной супергетеродин останется наиболее распространенной схемой построения приемника в диапазонах 8-12 ghz
milstar: https://www.ab4oj.com/sdr/flex/6700notes.pdf
milstar: http://irf-solutions.com/wp-content/uploads/2018/09/3822A-FOR-PDF.pdf The SMR-3822A Receiver, a member of the SMR-3000 family of high-performance synthesized microwave receivers, covers 0.1 to 20 GHz. Extension of the tuning range to millimeter wave frequencies is possible using the FE-3820 Frequency Extender. An internal Spectrum Display Generator (SDG) generates data that can be used to develop RF Sweep and IF Pan spectrum displays on a remote workstation or laptop. Simultaneous wideband IF outputs are provided at 1 GHz (500 MHz bandwidth) and 160 MHz (100 MHz bandwidth) in addition to a post fi ltered 160 MHz IF output. All IF outputs have a noninverted spectrum; in addition, there is operator selectable inversion of the IF up to 20 GHz tuned frequency.
milstar: The WJ8617B Receiver, Digital Quadrature Detector, andFFT post processor will form a wideband superheterodyne surveillance receiver Usystem which should offer a significant improvement in the probability ofinterception for signals in the 20 -1100 MHz range. This range is limited bythe range of the WJ8617B receiver. The system, illustrated in Fig. 1, willhave the capability of performing a 4096 point (4K) FFT in 20 msec. It willhave two modes of operation. In the coarse search mode, the FFT will beperformed on the entire 4 MHz bandwidth yielding a resolution of approximately1.5 kHz. In the fine search mode, the FFT is to be performed over a 200 kHzbandwidth, resulting in a resolution of approximately 50 Hz. A scanningnarrowband superheterodyne receiver requires approximately 2 seconds toperform an identical coarse search and at least 80 seconds to perform the samefine search. The improvement in search speed, achieved through widebandprocessing, increases the probability of interception of the spectral search.The improvement in probability of interception however, will be obtainedat the expense of a degradation in dynamic range performance. This reportwill examine the dynamic range performance of both wideband and narrowbandsuperheterodyne surveillance receivers. The analysis phase of operation willnot be considered since large dynamic range is not a primary concern in the Vanalysis phase. It will be shown that in general, dynamic range performancesuffers when a wider IF bandwidth is processed unless special consideration isgiven to the design of the receiver front end. In addition, it will be shownthat the applicability of certain dynamic range parameters as an indication ofthe receiver performance depends on the type of receiver used, as well as onthe type of post processing employed. Finally, anticipated dynamic rangeproblems specific to the surveillance system under development will beexamined. https://apps.dtic.mil/dtic/tr/fulltext/u2/a196569.pdf
milstar: 6In a scanning surveillance receiver (Fig. 4), the detection bandwidth isless than the frequency range of interest. The detection band is scannedthrough the range of interest to achieve complete coverage. The detectionbandwidth may be equal to the resolution desired, as in the case of anarrowband superheterodyne surveillance receiver, or it may be much largerthan the resolution desired, as in tae case of a wideband superheterodynesurveillance receiver. In the case of a wideband superheterodyne receiver,either parallelism or high speed digital processing is used in the postprocessor to obtain the desired resolution. The probability of interceptionfor a scanning receiver is a function of three parameters: the detectionbandwidth, the data acquisition time and the processing time. For a scanningsuperheterodyne receiver, the maximum scanning speed is given by: Bdet2Smax = (1)n + Bdet [Tp + Td]Smax-maximum scanning speed (Hz/sec)Bdet -detection bandwidth (Hz)Td -data acquisition time (sec)T -processing time (sec)n -constant indicating the detection filter settling time(settling time = n/Bdet)As https://apps.dtic.mil/dtic/tr/fulltext/u2/a196569.pdf can be seen from equation 1, if the data acquisition and processing timesare negligible, the scanning speed is proportional to the square of thedetection bandwidth. This is due to the settling time of the filter definingthe detection band. Typically n is 3 or 4, however for high Q filters it maybe more. 100% probability of interception is guaranteed only if the time toscan the entire frequency range of interest is less than the minimum signalduration.
milstar: http://www.vhfdx.ru/apparatura/twt_ra3eme Итак, какой выбор у нас есть? Пути решения проблемы получения достаточной для работы ЕМЕ мощности, а это примерно 50-60вт на диапазоне 6см и 20-30вт на диапазоне 3см две. транзисторный усилитель усилитель на ЛБВ Начнём с первого, такие усилители можно изготовить самому, для этого нам понадобится несколько транзисторов ценой 300-400$ за шт , свч материал для ПП и огромное везение, что транзисторы не китайские подделки и что они не вылетят при настройке. Готовый усилитель можно приобрести у известных производителей DB6NT или DL2AM по цене примерно 1800евро за 20вт мощности(что конечно ускорит ваше появление на свч диапазоне). Мне к сожалению эти цены пока недоступны, поэтому я пошёл по второму пути –ЛБВ Почему? – на то есть две причины: эти лампы ещё можно найти по реальной цене Высокое усиление, для получения выходной мощности в 90-100вт достаточно раскачки в 100-200мВТ Из недостатков- высокие питающие напряжения и низкий КПД (20-30%). Но учитывая цену 1вт то ЛБВ выигрывает. И самое важное для меня- на диапазонах выше 24ГГц кроме ЛБВ ничего доступного для простого смертного пока не придумали.
milstar: https://www.ab4oj.com/sdr/flex/6700notes.pdf ad9457 Flex 6700 test
milstar: Communication from linear to circular polarized antennas encounters a loss of about 3 dB which cuts into our margin of success. The prime focus dish is well understood. With advancements in feedhorn designs, efficiencies up to 67% are possible with antenna temperatures (Ta) in the range of 30°K as calculated and measured on a 20λ diameter dish(1). With a dish diameter of 10λ (about 2.4 m on the 23 cm band), gain is approximately 28 dBi. At a diameter of 1m, the dish offers about 20 dBi of gain which is the planned target https://ok2kkw.com/next/horn_23cm.pdf
milstar: Student’s success was noted in building 70 cm yagi’s for the EME test with Arecibo last year. A 23 cm test yagi was built but it was determined that this was not the way to go for the beginning builder. Construction and tuning yagis on 70 cm is far easier than 23 cm. Besides, one criterion is for the antenna to be converted easily to circular polarization with low losses which is where the yagi falls short at higher frequencies. The horn is one of the oldest antenna designs to choose from. The horn antenna is known for having a low noise temperature but lower efficiency for its size and material usage as compared to a properly illuminated dish. A look at optimum gain charts for a 20 dBi horn illustrates a horn size of 4 feet long and an aperture of approximately 3 feet square. This gain is assuming 50% efficiency. Noting this is about the same gain per aperture size as a 1m dish although more surface material is needed for a horn. The antenna temperature for the yagi was much higher than other antennas tested, but its lightweight and portability has advantages. https://ok2kkw.com/next/horn_23cm.pdf
milstar: Some thoughts on very small dish 10GHz EME https://wiki.microwavers.org.uk/images/3/38/20140514Thoughts_on_small_dish_10GHz_EME.pdf Small dish 10GHz EME is now a reality, bringing opportunites for intercontinental DX on 3cm to relatively modest stations. Microwave EME is no longer just the province of those with significant technical or financial resources. So what do I mean by modest? For the purpose of this note, I'm exploring the practicalities of making EME contacts with a typical 10W, 1m dish station using contemporary modulation schemes, particularly JT4 and JT65. Although I've been active on 10GHz 'off-the-Moon' quite successfully in the past on CW (and have been able to reliably copy my SSB echoes ...) with 50W and a good 2.4m offset dish, I' This is a small signal by any standard, but what receive sensitivity can we achieve? I'll assume a 2.5kHz bandwidth, as that fits-in with the WSJT EME reporting scheme. A receiver with a noise figure of 1dB (which is relatively easily achievable at 10GHz) equates with a noise temperature of ~75K. To that we need to add the noise temperature of the dish, which for a properly fed satellite TV dish will be about 30K, Polarisation Unlike the lower-frequency microwave bands, the vast majority of active 10GHz operators use linear polarisation. In order to circumvent spatial polarisation changes, European stations use local vertical polarisation, North Americans, horizontal, and antipodeans, vertical. As there is some spread of polarisation due to the way in which signals are reflected from the Moon, small differences in linear polarisation result in very small differences in received signal. I suggest that, at least initially, any new 10GHz EME system employs that convention. Of the relatively small proportion of stations currently using CP on 10GHz, most have sufficient reserves of system performance to work small linearly polarised stations. CP has been a 'hot topic' amongst 10GHz EME'ers for well over a decade! If you read the classic W2IMU EME notes, he has details of a CP antenna for 10GHz. There are a number of reasons why CP hasn't really caught-on at 10GHz, apart from inertia. One of the chief of these has been that, until relatively recently, good, reproducible, recipes for achieving circularity without introducing too much loss have been few and far between. Another reason is simply that the current linear polarisation protocol works very well indeed
milstar: Linear vs circular polarisation Up to 432MHz linear polarisation, whether vertical or horizontal, is used. Circular is not easy to arrange due to the need to provide for reverse circular polarisation switching due the moon reflection (polarisation reverses on reflection). On 1296MHz and above the use of dish reflectors makes dual polarisation feeds much easier to manufacture. Circular polarisation is almost exclusively used on the 1296, 2300/2304/2320/2400, 3400 and 5660MHz EME bands. At 10368/10450MHzthat is not always the case. Why? The nature of the moon at 10GHz is such that a significant amount of depolarisation takes place when signals undergo reflection. The size of surface obstructions, including boulders, can cause multiple scattering of signals and some areas of the moon permit significant subsurface reflection. All of this can make the use of circular polarisation less effective than it might otherwise be. Until recently the availability of low loss circular polarisation feed designs was poor. That has now changed and feeds based on the use of squeezed waveguide and septum polarisers are in common use. However, many fine examples of linear polarisation feeds, such as the once commonly used and available Chaparral feed, are available and still in common use. It happens that the majority of intercontinental activity takes place between Europe, North America, Australasia and Asia. These places are (approximately) separated by 90°. A signal transmitted to the moon at zenith will (mainly) return with the same polarisation. The same, vertically polarised, signal sent to the moon from, say, Europe, and received in North America with be received as horizontal. A standard has evolved whereby North American stations transmit to the moon using horizontal polarisation and Europeans use vertical polarisation. Australasia also uses vertical as it is 180° from Europe and 90° from North America. This system has been shown to work well and although there is theoretically up to a 3dB penalty when working any circular polarised station, depolarisation of the reflected signal often reduces this by several dB. For the beginner there is much to recommend the simplicity of linear polarisation. No doubt in the future circular polarisation will predominate, but it won't happen overnight.
milstar: What's different on 10 GHz EME ? https://pa0ehg.com/whatis.htm
milstar: Superheterodyne versus Direct RF Sampling https://blog.icomamerica.com/2016/03/15/ic-7300-a-game-changer/ https://www.icomamerica.com/lineup/products/IC-7300/?open=2 https://www.icomamerica.com/lineup/products/IC-7610/ https://www.icomamerica.com/lineup/products/IC-7851/ https://www.icomamerica.com/lineup/products/IC-R8600/
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