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eHam.net

eHam.net
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How to Use Your Antenna Tuner Just a few comments and corrections. "Say the antenna tuner is rated at 300 watts. OK, 300 watts at what impedance and reactance? Nope, that's not in the manual!" Well, it is in SOME manuals. "If you try and match very low impedance of say 15 ohms with that so called 300-watt antenna tuner with 100 watts the capacitors and switches will arc over from the several thousand volts developed across/through them. That a little bit of an exaggeration. Using about 200pF and the full capacitance at at power of 100 watts, we have 1600V on 3.5 MHz and 224V on 28 MHz. Now here is what is interesting. In a conventional T network the less capacitance used, the higher the voltage and loss. The worse place for using tuners is with a LOW impedance on low frequencies, and you should ALWAYS tune for maximum capacitance. "some type of Balun. Tuners are wisely getting away from 4:1 baluns now and using 1:1 baluns. "Simply connect the meter to the Balun. Not really. " What you need is an external 1:1 Balun. ".

Encyclopedia Encyclopedia : M : MO : MOR : Morse code Morse code is a method for transmitting information, using standardized sequences of short and long marks or pulses — commonly known as "dots" and "dashes" — for the letters, numerals, punctuation and special characters of a message. Originally created for Samuel Morse 's electric telegraph in the mid-1830s, it was also extensively used for early radio communication beginning in the 1890s. However, with the development of more advanced communications technologies, the widespread use of Morse code is now largely obsolete, apart from emergency use and other specialized purposes, including navigational radio beacon s, and by CW (continuous wave) amateur radio operator s. What is called Morse code today actually differs somewhat from what was originally developed by Alfred Vail in collaboration with Morse. Development The Morse code was developed so that operators could translate the indentions marked on the paper tape into text messages. The "!" Notes

Radio Society of Great Britain About Us - National Capital Radio & Television Museum The National Capital Radio & Television Museum operates in Bowie, Maryland, and also curates continuing exhibits elsewhere. Opened in 1999, the museum is open to visitors three days a week. Explore radio from Marconi’s earliest wireless telegraph to the primitive crystal sets of the 1920s, from Depression-era cathedrals and post-War plastic portables to the development of radio with pictures (a.k.a. television). This website details what we do, the services we offer, and the extensive benefits of museum membership.

RFspace SDR-14 Software Defined Receiver, RF Space sdr14 Specifications | Screens | Spectral Scan | Spectrograms | Front Panel | Rear Panel | F.A.Q. The RFspace SDR-14 is a 14-bit software defined radio receiver. It offers a broad range of spectrum analyzer and demodulation capabilities. Supported formats at this time include USB, LSB, AM, FM, WFM, CW, CWr and DSB. The SDR-14 comes with a High Frequency (HF) amplified frontend with switched attenuators and 1Hz tuning. One of the most exciting features of the SDR-14 is the ability to record band segments of any band to hard drive in real time. The SDR-14 operates from 12 VDC at 360 ma and comes with AC power supply, USB cable and computer CD. Please see the December 2005 issue of QST for an in-depth review of this radio on pages 63-66. View RFspace model comparison chart Products, technical data/technology, and services of RFSPACE INC.

Deutscher Amateur Radio Club Building the baseplate The baseplate is made of a 12 inch square type 6061 T6 aluminum plate that is 3/16 inch thick. This particular type aluminum is harder than pure aluminum and less likely to bend while being resistant to weather. U-bolts attach the spreaders to the baseplate.Two square base floor flanges normally used for handrails are used to mount the center post to the base plate. One is on the top for mounting the center post and the other is on the bottom for insertion of the mast. These flanges are made of aluminum-magnesium alloy.Stainless steel hardware can be used to minimize corrosion especially in saltwater environments although it is more expensive. Hexagonal Beam by K4KIO Building the G3TXQ Broad Band Hexagonal Beam Buy or build a hex beam Six Steps to build it - The Base plate The plate can be cut with a hacksaw by hand or by a reciprocating saw with a metal cutting blade. Measuring and marking the hexagon. A metal hole saw and a hand operated drill can be used to cut out the center hole.

Mars / Venus Express monitoring You have been redirected to this page because of one of the following reasons; Your IP address / subnet has been banned from visiting the site You have been caught mirroring content from the server - this carries a 1 month ban of your ISP You are a search engine and are crawling the site too fast Your countries IP address block is prohibited from viewing the contents of the site You have clicked a link to a image file on the site - hot linking is not permitted You have copied frequency information from this site without properly crediting its origin You are associated with the Zarya.info site and are therefore not permitted access to UHF-Satcom.com due to previous copyright violations An unspecified reason Mirroring content from the uhf-satcom website, without express permission, is illegal and is a copyright violation If you think you need access to the site, you can send your request and reason to; The base-line ban list is shown below;

Radioamateur Un article de Wikipédia, l'encyclopédie libre. Pour les articles homonymes, voir Radio. Le shack ou station d'un opérateur radioamateur. Les radioamateurs sont des personnes qui pratiquent, sans intérêt pécuniaire, un loisir technique permettant d'expérimenter les techniques de transmission et par conséquences d'établir des liaisons radio avec d'autres radioamateurs du monde entier. Beaucoup d'avancées technologiques sont dues aux radioamateurs, c'est par exemple grâce à eux que les fréquences au-dessus de 30 MHz sont aujourd'hui utilisées. L'activité radioamateur permet d'acquérir ainsi des connaissances techniques dans les domaines de la radio et de l'électronique et de développer des liens d'amitié entre amateurs de différents pays. Définitions de l'Union internationale des télécommunications[modifier | modifier le code] Service d'amateur[modifier | modifier le code] Service d'amateur par satellite[modifier | modifier le code] Radioamateur[modifier | modifier le code] Le HRO de 1950

A homemade 5-band Hexbeam antenna J-F. Zürcher, HB9MCZ updated April 7, 2009: new broadband hexbeam After reviewing dozens of antennas, I was convinced that the hexbeam represents the best compromize in terms of performance, dimensions, weight and wind load. So I decided to make my own one ... if possible with some original contributions! [1] the excellent commercial version of Mike Traffie [2] a very detailed description of the construction of a hexbeam [3] a lot of informations by a "hexbeam fan" [4] understanding the hexbeam, with a lot of informations and simulations My main source of inspiration has been reference [2]. As I have access to various machines (lathe, milling machine, ...), I decided to make a "semi-professional" realization: a rigid central baseplate made of two aluminium plates (6 mm thick!) TDR measurement of the square feeding line (central post)

53°44'N  0°26'W

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