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The article details antenna tuning procedures, emphasizing SWR measurement and adjustment for both mobile and base station setups. It explains that SWR (Standing Wave Ratio) is the ratio of transmitted power to reflected power, with high SWR indicating poor impedance match and potential damage to a transceiver's final amplifier. Specific instructions are provided for CB antennas operating between 26-27 MHz, recommending initial SWR checks on channels 1, 20, and 40 to determine if the whip needs shortening or lengthening. Adjustments should be made in small increments, approximately 1/4 inch at a time, aiming for an SWR of 1.5:1 or better. For _Ham radio_ and other antennas, the same tuning principles apply, with a strong caution regarding RF energy exposure when operating at higher power levels. The resource suggests tuning base antennas at ground or roof level before final installation to simplify adjustments. It also advises rechecking SWR after final installation to confirm no changes occurred. The _Alpha Rubicon_ resource highlights the importance of a good ground plane for mobile antennas and proper coax routing to avoid pinching or proximity to electrical wires.

This listing was put together by ve7vdx on the USENET rec.radio.amateur.space, and is updated weekly there

Over 65 years of radio manufacturing experience underpins Icom's extensive product line, ranging from handheld VHF/UHF transceivers to sophisticated HF base stations. The company's global website serves as a central hub for product information, technical specifications, and support resources for its diverse range of communication equipment. Hams can explore detailed specifications for popular models like the _IC-7300_ and the _IC-9700_, alongside commercial and marine radio offerings. The site provides access to product catalogs, firmware updates, and user manuals, ensuring operators have the necessary documentation for their Icom gear. Information on new product releases and technological advancements in radio communication is regularly updated, reflecting the company's ongoing commitment to innovation in the amateur radio market. Icom's presence extends across various radio segments, including D-STAR digital voice, marine, avionics, and land mobile, demonstrating a broad engineering capability beyond just amateur radio.

A half sloper antenna for 160 meter band Italian translation of a WD8DSB article appeared in a QST issue during 1998. This article presents a **Reduced-Size Half Sloper Antenna for 160 Meters**, designed for amateur radio operators with limited space. By utilizing a 40-foot tower or a tree, you can build an efficient antenna that slopes down, achieving a 2:1 SWR bandwidth of 120 kHz. This innovative design allows for effective communication on the "Top Band," making it ideal for winter DXing.

MMVARI is a multi-Mode SoundCard Ham (Amateur) Radio program for receiving and transmitting the RTTY-PSK-FSK-MFSK modes. The program was written to experiment with the efficiency of transmitting Japanese and East Asian languages (HL/BV/BY) using the VARICODE

hamOS is a live and installable Debian based linux respin for Amateur Radio Operators. It is intended for new users with little or no linux experience. hamOS contains a variety of pre-installed applications for amateur radio like logging, homebrewing, digital modes, and more.

The ZS6BKW multiband HF antenna, a design by ZS6BKW (G0GSF), functions effectively on multiple HF bands without requiring an Antenna Tuning Unit (ATU) for 40, 20, 17, 12, 10, and 6 meters. This antenna, approximately **27.51 meters** (90 feet) long with a 12.2-meter (40-foot) open-wire feeder, is a direct descendant of the _G5RV_ but offers superior multi-band resonance. It can be deployed as a horizontal dipole or an inverted-vee, with the latter requiring only a single support and maintaining an apex angle of at least 90 degrees to prevent signal cancellation. Performance data, recorded with an MFJ Antenna Analyser, indicates SWR values of 1:1 on 7.00 MHz (40m) and 14.06 MHz (20m), with SWR below 1.3:1 on 17m, 10m, and 6m. While primarily designed for these bands, the antenna can be adapted for 80m, 30m, and 15m with an ATU, preferably at the balanced feeder's base. The use of 450-ohm twin-lead for the feeder is recommended over 300-ohm for improved strength and reduced losses, especially in adverse weather conditions. This design, originally published in _RadCom_ in 1993 and featured in Pat Hawker’s "Antenna Topics," provides a compact and efficient solution for HF operation, particularly for those with limited space or resources.

Various ham radio cartoons

The G3TPW Cobwebb antenna covers five bands, 14 - 28 mhz, including the WARC bands

For amateur radio operators seeking a compact, directional antenna for the 10-meter band, this resource details the construction of a Moxon Yagi beam. The design utilizes readily available PVC pipe for the boom and elements, with specific measurements derived from the Moxon Rectangle Generator software. It outlines the assembly process for the main boom and end sections, providing critical dimensions for element spacing and overall length to achieve resonance at 28 MHz. The Moxon configuration offers a smaller footprint compared to a traditional Yagi, making it suitable for limited space installations. The article provides practical guidance for hams interested in a DIY antenna project, emphasizing the use of common hardware store materials. It specifies a 1 1/4" PVC schedule 40 pipe for the main boom and details the use of tees, reducing bushings, and 45-degree elbows for the element ends. Key measurements like the 55" spacing for the ends and the 150 3/4" overall length are provided, enabling replication of the design. The Moxon's inherent wide beamwidth and good front-to-back ratio make it an effective choice for DXing on 10 meters.

DarwinPsk is free to licensed ham radio operators and is a great application for PSK and RTTY communications under MacOSX

Solar Flux reports, Current Alerts and Warnings from NOAA, 27 day forcast from NOAA, charts reflecting the past 7 years Solar cycle summary charts from NOAA

A DIY discone antenna project made to improve receiveing performance of an RTLSDR receiver.

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

"ARES trains and organizes Hams to provide emergency communications to ""Served Agencies"" such as FEMA, National Weather Service, Red Cross, Salvation Army, Hospitals, and others. This site describes ARES goals and methods and structure."

N2DS home made loop page collection.

HamFax is an application for sending and receiving facsimiles in amateur radio and for receiving public facsimile broadcasts like weather maps. Supported interfaces are sound cards and the SCS-PTCII from Special Communication Systems.

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.

Collection of Amateur radio packages for the Raspberry Pi devices

G4NCE's illustrated vintage military wireless collection. Featuring British, Canadian and New Zealand Army eqpt, and Royal Air Force eqpt, from WW2 and the 1950's.

2 element Yagi antanna plan from G3SYC

Tim Kirby IC-706 review of this small portable Icom transceiver

Kenwood TS-2000 Review

Download the PDF with USA Amateur radio HF band plan and common country prefixes updated in 2008 by Icom

Halo antenna for 4 meters band with dimensions, pictures and assembling instructions

A small multiband antenna for vacation in french

Service Manuals & Schematics, supplied for most types of equipment, Audio, TV, Video, Test and Ham Radio

The Adcock antenna has been used for a long time for RDF. It is basically an interferometer.

OZ2OE Technical pages, a 3 element 28 MHz light weight Yagi for 10 meters band

RTTY Tutorial by K4WW, foundamentals, FSK and AFSK

The K5OE 2-meter vertical mobile antenna design, detailed in this resource, employs a 3/8-wavelength vertical section complemented by four shortened radials, forming an off-center-fed vertical dipole. This configuration creates a self-contained lower half, enhancing efficiency compared to traditional 1/4-wave monopoles relying on vehicle bodies for a ground plane. The article specifies construction using PVC components, 10-gauge insulated wire for elements, and provides precise dimensions in both inches and centimeters for the 25-3/16" (64 cm) vertical and 7-3/16" (20 cm) radials. Performance data indicates an honest 3 dBi of gain at 6 feet elevation (2 dBi free-space), with a pattern favoring the horizon, suitable for Low Earth Orbit (LEO) satellite communications. At 20 feet high, the same antenna exhibits almost 6 dBi of gain, with a nominal 50 Ohm feedpoint impedance at 146.850 MHz. Tuning instructions involve trimming element lengths, with the author achieving a 1.2:1 SWR by pruning the mast to 24-3/4" and radials to 7". The resource highlights the antenna's effectiveness for mobile LEO satellite uplinks, particularly at low elevations, and its suitability for fixed, mobile, or portable operations. The flexible wire elements allow for easy folding, making it a practical choice for backpacking. The original design by K5OE was previously hosted on aol.com.

A friendly dx net who welcomes new comers to amateur radio and the serious dxer alike; Daily from 2000gmt on 14.208mhz. Listen the net live.

Indoor wire antenna for 7 mhz from F6CYV

If you have a small lot and want on 160 meters this is our version of the antenna by K5CBL Troy

Presents the product lines and corporate information for Japan Radio Company (JRC), a long-standing manufacturer of radio communication equipment. The company's offerings span various sectors, including marine, land, and aviation communication systems, alongside their historical contributions to amateur radio with notable **HF transceivers** and **shortwave receivers**. JRC emphasizes its technological expertise in areas such as radar, satellite communication, and network solutions, contributing to global safety and security infrastructure. The resource details JRC's commitment to leveraging its accumulated knowledge and experience in information and communication technology. While the primary focus has shifted towards commercial and governmental solutions, the legacy of JRC's amateur radio products, such as the JRC JST-245 transceiver and the NRD-525 receiver, remains significant within the ham radio community, known for their robust build quality and performance.

500 W, KW and 6M ham radio amplifier kits for export

Ham radio humor with something for all ages. Check out the letters from a Tennessee hillbilly ham! Have a laugh er two!

Amateur Radio experience, blog from Florence Italy

Picture and construction details of a 5 element 20 meter monobander

Broadband dipole antenna, needs an antenna tuner but can reach 3db gain over dipole

An AO-10 antenna by K5OE, this design is optimized for 436.8 mHz with a 50 Ohm feed

The QM7 antenna is a simple 7 elements Yagi with 3.70 m boom length for the lower 144 MHz SSB/MGM band, used it mainly for Sporadic-E and MS contacts. It exhibits a forward gain of 11.35 dBd; i.e. 13.5 dB forward gain over the isotropic radiator, while the F/R is about 12.5 dB

HamRadioHomebrew Cat Interface for Yaesu FT-897 by PE1OPM

Ham Radio Antenna Tuners--Full Legal Power--Patented Circuit--Outstanding Efficiency and Power Capability

A homebrew project for a 2 meter 4 element yagi beam antenna by 2E0HTS

The Clemens match is easy to make and reliable, and is preferable to a single Gamma match as it is balanced

The W3DZZ trap dipole is a versatile and economical antenna option for amateur radio operators looking to work multiple bands without the need for extensive equipment. This antenna design utilizes traps to allow operation on various HF bands, making it suitable for both casual operators and serious DXers. Its construction is straightforward, making it accessible for beginners while still providing excellent performance for seasoned hams. Constructed with readily available materials, the W3DZZ trap dipole can be built to fit specific band requirements, allowing operators to optimize their setup for the frequencies they intend to use. The design is particularly favored for its ability to maintain a low profile while delivering effective radiation patterns. Whether you're contesting or chasing DX, this antenna can enhance your station's capabilities without breaking the bank.

A stacked Jpole antenna plan by Gary - KGØZP

Ham Radio applications with the Arduino micro-controller presentation

Theory and operantions, G5RV construction tips by Keith, KE2DI