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A Portable VHF-UHF Roll-up J-pole Antennam that resonates on both bands but actually performs as a half wave radiator on both bands

TVI and BCI bandpass and bandstop filters in SMD technique. Schematics and images.

Autotena, a Taiwanese manufacturer, offers a diverse product line focused on RF communication antennas and related accessories. The resource details various antenna types, including **4G/3G LTE wideband high-gain low-profile antennas**, land mobile wideband antennas, fiberglass omnidirectional designs, and GPS mobile and marine antennas. Specific amateur radio offerings include NMO VHF load coil gain antennas, VHF whip gain antennas with PL-259 connectors, and UHF NMO mount antennas with 3dB/5dB gain. The company also produces antennas for CB and 10-meter amateur bands, such as aluminum broadband 26-30MHz antennas and big copper coil broadband 26-30MHz antennas. Additionally, the site showcases **RF amplifiers** for CB, HF, VHF, and UHF bands, including professional-grade base station amplifiers with 100% EIA duty cycle. Handheld antennas, PL-259 type mobile antennas, magnet mount antennas, and external CB speakers are also presented, alongside various mounting kits and cable assemblies.

An ARRL guide to where on the HF bands various modes and activities are generally found.

A small antenna for all amateur bands, including 80 meters, and in a small garden without the compromise. An ideal replacement for those half size antennas such as the 1/2 size G5RV and Windom 40

Dual band J pole operational over the entire 6Mtr band (50 - 54MHz) and the entire 2Mtr band (144 - 148MHz), slightly favouring the upper half of both bands by VK6YSF

A simple and low cost multiband vertical hf antenna covering 5 bands (20m-10m) from an old CB antenna

A shorten Dual-Band Dipole with overall length of about 11 m. For this antenna traps are substituted by inductors, in order to cover the 10 & 40 m. Bands.

A large worldwide map of aeronautical service Frequencies allocation on HF bands dated 2002

Over 75 years of engineering expertise underpins Bird Electronic's offerings in RF power measurement, critical for maintaining peak performance in amateur radio stations and professional communication systems. The company specializes in a range of test equipment, including wattmeters, SWR meters, and antenna analyzers, essential for optimizing antenna systems and ensuring efficient power transfer. Their product line extends to various RF components such as filters, cables, and connectors, all designed to meet stringent technical specifications for reliability and accuracy across diverse frequency bands. Bird Electronic's instruments, like the _Bird 43_ Thruline Wattmeter, are widely recognized for their robust construction and precise measurement capabilities, providing hams with confidence in their station's operational parameters. These tools enable accurate assessment of forward and reflected power, SWR, and modulation characteristics, which are vital for troubleshooting and maximizing radiated power. The company's commitment to innovation ensures that its products remain relevant for modern RF challenges, from HF through microwave applications, supporting both traditional analog and advanced digital modes.

G3YCC article pn the W3EDP end-fed antenna for 80 to 20 meters bands

Simple, inexpensive and easy to erect, this antenna provides directivity, low angle radiation and a small gain on a number of HF bands.

The Answer To Suburban DXing On the Low Bands - by Merv Schweigert, K9FD

The Buddipole is a hi-tech, take-apart dipole designed for HF portable operations. The antenna uses a multi-band adjustable coil for all bands 40m - 2m.

How to build a high gain vertical antenna for the UHF amateur or CB Bands, by radio experimenters handbook

Operating a G5RV antenna effectively often raises questions regarding its installation and performance across various bands. This archived discussion from the TowerTalk mailing list captures a real-world exchange, where KI0DZ shares practical insights from her own setup. She details her G5RV strung diagonally between trees, sloping from 25 feet to 10 feet, and notes its use with a Yaesu FT-757's automatic antenna tuner. KI0DZ recounts working 80 meters with 100 watts, achieving contacts up to 1000 miles, and confirms the general requirement for an antenna tuner. The thread also touches upon the G5RV's performance in an inverted V configuration, with a recommended angle of at least 90 degrees, and the ease of building one's own versus purchasing a manufactured version. While not an "antenna expert," KI0DZ's field results and direct experience provide a useful perspective on the G5RV's capabilities for "modest purposes" across multiple bands, offering practical answers to common inquiries about height, configuration, and band coverage.

CB2HAM is a group for licensed radio amateurs focussed on converting quality CB radios over to the Ham bands.

The FL-2100Z amplifier referenced in the following images is the 6-Band model covering 10m thru 160m (no WARC bands) and not the 9-Band version that included the WARC bands. Modifications, schematics and manual

This is the most advanced scanner software for the AR8200 and the AR8600. It can effect any type of scan, can scan from 1KHz to 3000MHz in one time. The AREight is a software for help you to listen signals from around the globe on the shortwave bands

The 6 Band Inverted L Antenna MK3 is a versatile multiband antenna designed for amateur radio operators. This antenna covers 160m, 80m, 40m, 20m, 15m, and 10m bands, making it suitable for a wide range of HF communications. The design is based on a W3DZZ configuration, incorporating traps for optimal performance. The MK3 version features a sturdy 5/8th CB mast, replacing the original timber mast, which enhances durability against harsh weather conditions. The antenna's construction allows for effective operation, particularly on the 40m band, where it has been successfully used to contact distant locations including ZL, VK, and Antarctica. Constructing this antenna requires careful attention to detail, especially regarding the radials and grounding. The traps resonate at specific frequencies, and additional resources are available for building coaxial traps. The antenna is designed to work efficiently without an ATU on the lower bands, while higher bands may require tuning. This project is ideal for both beginner and intermediate operators looking to enhance their station with a reliable multiband antenna.

Described is a simple inverted-V antenna which, when used with a balanced ATU, can be used on all the main Radio Amateur HF bands (80, 40, 20, 15 and 10m). The cental support is made in such a way that the wire can be coiled up for storage when the antenna is taken down.

The alternative multi-band solution, covers more bands than a G5RV, light weight, won't damage your trees.

Theory, Modeling, and Practical Applications By W5JCK, presentation in PDF File. This presentation focuses on Near-Vertical Incidence Skywave (NVIS) antennas, which are crucial for short-range radio communications, particularly in military and emergency contexts. It explores NVIS theory, antenna models, and installation criteria while debunking common myths about reflectors. Key topics include usable frequency bands, optimal installation heights, and the impact of soil quality on performance. The presentation outlines the best bands for daytime and nighttime use, emphasizing the importance of understanding propagation characteristics to enhance communication effectiveness within 200 to 300 miles.

A broadband travelling wave dipole for HF bands, whose VSWR is less than 2:1 from 3 to 15 MHz and does not exceed 2.6 to 1 from 2.3 to at least 30 MHz

An RF power amplifier, providing 7 Watts output in HF bands, schematic by ON6MU

The G5RV antenna, a popular multi-band wire antenna, typically employs a center-fed design with a specific length of 300-ohm or 450-ohm open-wire line acting as an impedance transformer, feeding a coaxial cable run to the shack. Its overall length for 80-10 meters is approximately 102 feet (31 meters) for the flat-top section, with a 34-foot (10.36 meter) matching section. The original design by Louis Varney, G5RV, aimed for efficient operation on 14 MHz (20 meters) as a 3-half-wave antenna, with the matching section providing a good match to 50-ohm coax on that band. While the G5RV offers multi-band capability, its performance varies across bands, often requiring an antenna tuner for optimal SWR on bands other than 20 meters. The matching section's length is critical for its impedance transformation properties, influencing the feedpoint impedance presented to the coaxial cable. Variations like the G5RV Junior and ZS6BKW utilize different flat-top and matching section lengths to optimize performance for specific band sets or to achieve a lower SWR without a tuner on certain bands, demonstrating the adaptability of the basic G5RV concept.

The page provides detailed information on coax stub filters for multi-transmitter setups, including specific lengths for different bands and types of coax. It also references additional technical notes for further analysis.

This page is a short description of the four phased verticals system i've build and used. It is primarily intendend to be used on the lower bands 160m, 80m, 40m.

IZ7GJX Comparing Kenwood TS-2000 to Icom IC-7000 on various ham radio bands

This Yagi has a constant element-distance of 1,50 m. You must only correct the lengths of the elements for QSY, see table down. For the bands 10 m and 12 m the Yagi is working as a reflector-radiator-Yagi, for 15 m and 17 m as a beam with radiator and director.

The Chameleon V1 HF Multiband Antenna is a mobile antenna that can also be used as portable. Lightweight mil whip antenna system with 10 BANDS capability 6m, 10m, 12m, 15m, 17m, 20m, 30m, 40m, 60m & 80m.

A 40 ft vertical dipole antenna that can cover HF Bands from 80 to 10 meters winding a dipole in a 12m HD telescoping fiberglass pole

An article on TX and RX antennae for the low bands 80 and 160m by EI7BA

Members only articles on HF mobile antennas, includes an interesting RV antenna with a 5 bands coverage, and another similar antenna for camper.

A project for a portable antenna for amateur radio satellite reception, for 2 meters and 70 centimeters bands

The RigPix database entry provides a comprehensive technical overview of the Icom IC-746 amateur HF/VHF transceiver, detailing its operational parameters and physical characteristics. It specifies the transmit frequency ranges across 10-160 meters plus WARC bands, 50-54 MHz, and 144-146/148 MHz, alongside receive coverage from 0.03-60 MHz and 108-174 MHz. The resource outlines supported modes including AM, FM, SSB, CW, and RTTY, noting a tuning step resolution down to 1 Hz and a frequency stability of ±5 ppm. Key electrical specifications are presented, such as a 13.8 VDC power supply requirement, current drain figures for RX (1.8-2 A) and TX (Max 20 A), and RF output power ranging from 5-40 W for AM and 5-100 W for FM, SSB (PEP), and CW. The entry details the triple conversion superheterodyne receiver system, listing IF frequencies at 69.01 MHz, 9.01 MHz, and 455 KHz, along with sensitivity ratings for various modes and bands. Transmitter section specifics include modulation systems and spurious emission levels. Additional features like a built-in auto ATU, electronic keyer, simple spectrum scope, DSP, and CI-V computer control are noted. The page also lists related documents, modifications, and an extensive array of optional accessories, including various filters, microphones, and external tuners, providing a complete profile of the IC-746.

German article on the multiband dipole by DG0KW. This antenna can be configured for several bands and can work in 3 or 4 bands mode. Can be used in restricted space lots.

Presents the design and construction of the OK2FJ Bigatas, a portable, automatically tuned vertical antenna covering 80 through 10 meters. It details two distinct control systems: one utilizing BCD band data from Yaesu FT-857/897 transceivers, and another employing voltage level sensing for the Yaesu FT-817. The resource provides specific instructions for building the antenna's radiating element, loading coil with switchable taps, and the control circuitry, emphasizing the use of readily available components. The article outlines the physical construction of the antenna, including the use of duralumin tubes for the radiator and a PVC tube for the coil form. It specifies coil winding details, tap points, and the integration of radial wires for ground plane operation. The control electronics section provides schematics and component lists for both the BCD decoder (using a 74LS42 IC) and the voltage comparator (using an _LM3914_ bargraph driver), enabling rapid, automatic band switching without the minute-long tuning delays common in other systems. Crucially, the antenna achieves rapid band changes, with typical SWR values centered on common operating segments, such as **3.7 MHz** for 80m SSB. It also discusses modifications for CW operation on 80m and the trade-offs between antenna efficiency and full-range automatic tuning on higher HF bands, where manual adjustment of radiator length is suggested for optimal performance on 15m, 12m, and 10m. The resource includes construction photos and a discussion of cable requirements for reliable operation.

This resource details the computer-optimized design of the _ZS6BKW_ multiband dipole, an evolution of the classic _G5RV_ antenna. It begins by referencing the original 1958 RSGB Bulletin article by Louis Varney G5RV, explaining the operational principles of the G5RV's flat-top and open-wire feedline on 20m and 40m, noting its impedance transformation characteristics for valve amplifiers of that era. The article then transitions to the rationale for optimizing the design for contemporary solid-state transceivers requiring a 50 Ohm match. The core of the project involves using computer modeling to determine optimal lengths for the flat-top and matching section, aiming for a VSWR of less than 2:1 on multiple HF bands. It discusses the process of calculating feedpoint impedance based on antenna length and frequency, referencing professional literature from Professor R.W.P. King at Harvard University. The analysis also considers the characteristic impedance (Z(O)) of the open-wire line, identifying a broad peak of adequate values between 275 and 400 Ohms. Specific design parameters for the improved ZS6BKW are presented, including a shorter flat-top and a longer matching section compared to the original G5RV, with a velocity factor of 0.85 for the 300 Ohm tape. The article confirms acceptable matches on 7, 14, 18, 24, and 28 MHz bands when erected horizontally at 13m, and also discusses performance in an inverted-V configuration, noting frequency shifts. The author, Brian Austin ZS6BKW, emphasizes the antenna's suitability for modern 50 Ohm coaxial cable without a balun.

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

A ranking of receiving antennas based on noise being evenly distributed in all directions. These rankings are most accurate in the frequency range of AM broadcast, 160 or 80 meter bands

Amateur Television (ATV) operations, particularly within the Arizona region, require dedicated resources for technical information, operational guidance, and community engagement. This club provides a focal point for hams interested in transmitting and receiving video signals on amateur bands. Members engage in local ATV repeaters, participate in technical discussions, and share knowledge on video modulation schemes, antenna designs, and station configurations. The club supports activities ranging from local simplex contacts to wider area repeater usage, fostering skill development in this specialized mode. The organization maintains a roster of club officers and offers membership opportunities to local amateurs. It also curates offsite links to other ATV resources, expanding the knowledge base available to its members and the broader amateur community. The club's emphasis on ATV helps propagate interest and technical expertise in a mode that combines traditional RF engineering with video technology.

Allow 9 bands and 1300 Watt output on the TL-922 amplifier with this document by PA0FRI

Presents a comprehensive guide for constructing a broadband Hex Beam antenna, a popular directional array for HF operation. This design offers a compact footprint and excellent gain characteristics, making it suitable for limited space installations while providing significant performance advantages over omnidirectional antennas. The resource details the specific dimensions for a five-band Hex Beam covering 20, 17, 15, 12, 10, and 6 meters, emphasizing the critical element spacing and wire lengths required for proper resonance and pattern. It outlines the construction of the center post, spreaders, and wire elements, along with the feed point assembly, ensuring proper impedance matching. The project aims for a forward gain of approximately **5.5 dBi** on most bands, with a front-to-back ratio often exceeding _20 dB_. Building this antenna requires careful measurement and assembly, but the resulting performance provides a substantial upgrade for DXing and contesting.

Hexagonal wire beams for all hf bands, technical resource, EZNEC files, tools for antenna modeling and documentation. You can also order parts to build your own antenna.

Antenna covers all bands 80-10 meters + 30, 17, 12 meter WARC bands, need a lot that is at least 100 feet across.

3 Band vertical Marconi-antenna for the bands 40, 80, 160 meters with a ground net of wires as radials.

MMMonVHF maintains the data for 6m, 2m, 70cm and 23cm bands in collaboration to LA0BY. This site allow display of a beacon map and latest beacon spots.

WY3A Homebrew G3TXQ Hex Beam for 5 bands

A homebrew fishing-rod vertical using a very nice design from EB5EKT. This antenna works 20, 30, and 40M bands by selecting the tap points using alligator clips