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EI7BA Multiband Cubical Quads projects, includes two elements quad antennas for 10 12 15 17 20 meters band. Performance considerations, detailed pictures and construction notes.

Effective HF Mobile Antennas Keith WB2VUO, explains difficulties on gaining antennas efficiency on lower bands with mobile antennas.

RFI Kit, ferrite cores, baluns, loop antennas, antenna tuners and various accessories

a Javascript for calculating the lengths of tubing to be used for the construction of a Super J-Pole.

Selecting an appropriate antenna system for shortwave broadcasting involves evaluating various types based on performance, cost, and operational parameters. This resource details the critical specifications for broadcast antennas, including average and peak power ratings, directivity, takeoff angle (TOA), horizontal beamwidth, and gain, emphasizing that a 100-kW transmitter requires an antenna rated for 150 kW average and 400 kW peak. It clarifies that low TOA signals travel thousands of kilometers, while high TOA is for local coverage, and nearly all modern shortwave broadcast antennas are horizontally polarized. The article explores specific antenna types, such as Log-Periodic Antennas (LPAs), which offer wide frequency ranges (e.g., 2-30 MHz) and directional patterns with 11 dBi gain, costing from $20K to over $100K for multi-curtain versions. Dipole arrays, also known as curtain antennas, are prevalent in international broadcasting, featuring steerable beams (±15° and ±30°) and mode-switching capabilities to alter TOA, with high/low pairs costing over $1 million. Fan dipoles are noted for omnidirectional patterns, smaller size, and lower cost for low-power applications, while rhombics, though simple, require resistive termination and incur several dB of I2R losses. Balun considerations are crucial, as most communications baluns are not rated for the higher average and peak powers of AM broadcast transmitters. Modern shortwave antennas utilize durable materials like Alumoweld wire rope for radiators and support elements, avoiding copper, fiberglass, or materials prone to stretching or deterioration. Feeder systems for high-power stations often require tapered-line baluns to convert 50-ohm unbalanced power to 300-ohm balanced for connection to the antenna.

K6SGH hamloop antenna for 15 meters band

A description page on how build delta loops antennas. In italian

Paddles, Keys, Filters, Antennas

Shakespeare Composites & Electronics Division manufactures a complete line of unmatched CB, CB marine, and military antennas for a veriety of applications.

How High should my Dipole be? Dipole Antennas - the Effect of Height Above Ground

Vertical antennas for all HF bands, expecially 80 40 20 meters bands

Rigid Dipole antennas for 14 MHz band using PVC and Aluminium tubing

Three eh antenna plans for 20 40 meters bands.

Drawings of shortened antenna for indoor usage, using short pvc tubes for 2 , 20 and 40 MHz by f1rfm

Magnetic loop antenna calculator and loop antenna design program for windows let you calculate dimensions for magnetic loops antennas, in german

A new tronics company, antenna maker, HF vertical antennas, vhf antennas, cb antennas

GAP produces HF vertical antennas

Perfect ground vs. poor ground. What is the difference? How does the ground influence the DX-gain?

Weather demodulator software, cards and antennas.

This projects was developed as a result of experiments to become QRV on 80 meters, again, using the little balcony by SM0VPO

Interesting article on mobile antennas by Cebik. . The article offers advice for setting up and operating mobile antennas for ham radio use. It emphasizes the lossy nature of mobile-in-motion antennas but encourages users to rise to the challenge. Steps include safeguarding car electronics, choosing proper cabling, and carefully selecting and mounting antennas. It highlights potential issues like roof mounting, trunk lip grounding, and side-mounting for trucks. For stationary operation, options like dipoles or beams are explored, with safety tips for masts and guying systems. Lastly, it stresses safety, suggesting stopping the vehicle to operate whenever possible

Design and build your own Hf thru Vhf antennas.Contains pictures, plans, parts list of very popular ham antennas along with experimental types.

So you want to build a Beverage Antenna. This article offers insights on building a two-wire Beverage antenna for better reception. Key points include using long wire (at least a wavelength, ideally two), keeping it straight and away from vertical conductors, and sloping ends for noise reduction. The author recommends copper clad wire and mentions transformer design considerations for later discussion.

Slinky Antenna Basics, clandestine dipole

Builing a triple ration balun, that match resonant antennas from 9 ohms to 75 ohms with 1.5:1 or less SWR

All copper J-Pole antennas for sale. 6 meter, 2 meter, 222 MHz, 440 MHz, LPFM, Marine, GMRS. Includes a construction plan in pdf format if you wish to build your own antenna.

802.11b WLAN Waveguide Antennas Unidirectional & Omnidirectional. High gain, Simple construction by Trevor Marshall

Over 40 years of experience inform the reviews and commentary presented on Dave's Radio Receiver Page, covering a wide array of radio receivers and transceivers. The resource details specific models such as the **ICOM IC-R8600** SDR Communications Receiver, which is lauded as Icom's best wide-band receiver, even surpassing the IC-R9500 in performance. Other notable reviews include the ICOM IC-7300 HF Transceiver, highlighting its direct sampling SDR technology and spectrum scope capabilities, alongside numerous models from Japan Radio Co. (JRC), Kenwood, Yaesu, and various portable shortwave receivers. The content provides practical insights into the performance and characteristics of each radio, often drawing comparisons between models. For instance, the early issues with the AOR AR7030 receiver's Bourns mechanical encoders are thoroughly documented, including AOR's eventual switch to higher-quality Alps encoders. The page also features reviews of antennas like the MFJ-1026 Noise Canceling Signal Enhancer and various power supplies, offering a holistic view of radio monitoring setups. The author's "2 ear / 2 eye method" emphasizes real-world listening experiences over laboratory measurements, providing a unique perspective on equipment utility.

Method of storing my portable wire antennas.

HF Ham Radio mobile operation antennas manufacturer, W6HIQ, HA5CMG, VE7BOC, HF mobile antennas, screwdriver antenna, coils and filters.

What is NVIS Near Vertical Incident Skywave. This article on NVIS (Near Vertical Incidence Skywave) explores its role in short-range HF communication, covering 0-200 miles. NVIS utilizes antennas with high radiation angles and frequencies below the ionospheric critical frequency to achieve reliable local contact. He details optimal antennas, like low dipoles, and practical tips for maximizing NVIS performance, emphasizing its advantages such as reduced noise and independent operation without repeaters. However, challenges include frequency sensitivity and the need for appropriate antenna setups at both ends for effective communication.

Article and comparison between bazooka antennas and dipole, taking care of effieciency and bandwidth

N2DS home made loop page collection.

Balcomy antenna modification to cover top bands, by Harry Lythall SM0VPO

The **NW3Z** optimized wideband antenna designs, originally presented at Dayton 2001, detail Yagi configurations for the 20-meter, 15-meter, and 10-meter amateur radio bands. This resource provides access to the design files, likely containing critical parameters such as element spacing, element lengths, and boom dimensions, which are essential for replicating these directional antennas. The designs focus on achieving wide bandwidth, a desirable characteristic for contesters and DXers operating across a significant portion of each band. The content specifically references "nw3z-Antenna-DesignsDownload," indicating that the core information is available as a downloadable file, presumably in a format suitable for antenna modeling software or direct construction. Such files typically include **NEC models** or similar data, allowing for performance analysis and optimization before physical construction. The emphasis on "optimized wideband" suggests design considerations for SWR bandwidth and gain characteristics over a broader frequency range than typical narrow-band Yagis. The resource serves as a direct source for specific, proven antenna designs from a known amateur radio antenna designer, offering practical data for hams interested in building high-performance Yagi arrays for HF.

Basics and principles of the HB9CV antenna by Rudolf Baumgartner. This antenna join electric advantages of the two elements direct feeded aerials with the mechanical advantages of the Yagi antennas, in French.

Antennas, books, rf parts, tubes,connectors and cables and many accessories at RF parts.

Using delta match with HF antennas design

Antennas, base mobile scanner and vhf antenna, coax cables, coax switch, Lightning Arrestor, mounts, power supply, speakers and wattmeters

Reduced size longwave antennas by Cesare Tagliabue I5TGC and his experience on 136 kHz band.

Manufacturer of communications antennas, bandpass filters, RF combiners, receiver multicouplers, diplexers, duplexers, RF connectors, RF circulators, RF isolators, RF couplers and SWR meters

Isotron antennas are low-profile HF antennas. If you need a small antenna, then an Isotron may be the answer. Bilal isotron antennas.

Sharing beverage antennas with this switch boxes is possible. This article describes a 6-position remote antenna switch for Beverage antennas on 3 bands (160m, 80m, 40m). It allows selecting one of 6 antennas for each band without affecting other receivers. The system uses a control box with a rotary switch and a separate splitting box with bandpass filters for each band.

How to make a Weatherproof Vertically Polarised Omnidirectional Aerial, The Slim Jim Antenna

An interesting article on NVIS antennas, explaining basics of NVIS antennas and the main usage of this particular aerials by Patricia Gibbons

Suppliers of Amateur Radio equipment, Antennas, accesories MFJ, Ameritron, Mirage, hardware and software for digital modes.

Quad and Yagi portable antennas for 50 mhz by VE7CA

Base station antennas, now andrew corp.

Why quads are considered best antennas by ve3sqb

Various Yagi antennas for 70 Mhz band