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For every radio amateur who loves to travel by car, a mobile installation soon becomes a necessity. While in inhabited areas there is usually some coverage of VHF repeaters, in many other places VHF radios are useless. In these very places, HF can provide reliable contacts, and a lot of fun, from anywhere.

Operating in a Single Operator Two Radios (SO2R) setup, especially with beverage antennas, often exposes the receiving radio's front-end to significant RF energy from the transmitting radio. This resource details a practical, homebrew receiver protection circuit designed to mitigate this risk. The core of the design involves a non-inductive 2W 22 Ohm carbon composition resistor in series with the RX antenna line, followed by two stacks of four fast-switching diodes (e.g., _1N914_) configured in opposite polarizations. This arrangement effectively clamps the incoming voltage to approximately 2.8 V peak-to-peak, safeguarding sensitive receiver input components. The series resistor plays a crucial role by absorbing excess power, preventing the diodes from exceeding their current ratings and potentially failing open, which would leave the receiver unprotected. The author, _N4KG_, measured up to 50 watts of coupled power between 80M slopers on the same tower, highlighting the necessity of such protection. The design is presented as a cost-effective solution to prevent damage to receiver input transformers, with the author noting successful protection of a receiver even after a resistor showed signs of overheating. This simple circuit can be integrated via a transverter plug, offering a robust defense against high RF input.

A quarter wave vertical omni-directional antenna for 7 MHz. Formulas for dimensions in feet and meters are provided. Ideal radial angle is between 35° and 45°. Velocity factor (Vf) varies based on coax type.

Voldatech, a manufacturer based in China, produces a range of RF feeder cables and site components essential for amateur radio installations and telecommunication infrastructure. Their product line includes various types of coaxial cables, such as **50 Ohm** and 75 Ohm options, along with a comprehensive selection of connectors like N-type, UHF, and BNC. These components are critical for maintaining signal integrity and minimizing loss in antenna systems, whether for a home shack or a remote DXpedition setup. The company's focus on _RF Coax cables_ and connectors directly supports the needs of radio amateurs seeking reliable transmission lines for their transceivers and antennas. Amateurs often compare Voldatech's offerings to established brands, evaluating factors such as impedance matching, shielding effectiveness, and durability under various environmental conditions. The availability of diverse cable types allows operators to select optimal solutions for different frequency bands and power levels, from QRP to high-power amplifier setups. Their products are particularly relevant for those constructing new antenna arrays or upgrading existing feedline systems, aiming to achieve maximum power transfer and reduce standing wave ratio (SWR) for efficient signal propagation.

DF0WD/DL4YHF's Longwave Overview details amateur radio operations on the 135.7 to 137.8 kHz segment in Germany. The author outlines the "inofficial" European band plan, specifying segments for QRSS, TX tests, beacons, conventional CW, and data modes. Early LF activities at DF0WD began with a 20-watt CW transmitter, later upgraded to a homemade linear transverter capable of 100 watts, driven by an Icom IC706 on 10.137 MHz. The station's antenna system includes a 200-meter wire, approximately 10 meters above ground, supported by football field light-masts. Despite its length, the antenna's efficiency is noted as very low due to the immense wavelength of about 2.2 km. The author's experience highlights the significant challenge of achieving effective radiated power (EIRP) on LF, estimating DF0WD's EIRP at around 80 milliwatts based on field strength measurements from PA0SE. DF0WD/DL4YHF has successfully worked numerous countries on 136 kHz CW, including DL, F, G, GI, GM, GU, GW, HB9, HB0, LX, OE, OH, OK, OM, ON, OZ, PA, and SM. The author also mentions ongoing efforts to log contacts with CT, EI, LA/LG, and to complete a two-way QSO with Italy, demonstrating persistent activity on this challenging band.

MARCA, Inc. operates approximately 24 repeaters across Arizona mountaintops and Phoenix-area rooftops, supporting modes like D-STAR and Fusion. The club, holding the **W7MOT** callsign, engages in diverse activities including ARRL Field Day events near Forest Lakes, AZ, ARRL FMT contests, and antenna experimentation. Members actively participate in HF operations such as voice, digital, CW, DXing, and various digital HF modes, alongside MESH and EOC operations within the valley. The club's interests span a broad technical spectrum, from SDR radio building to antique radio restoration, and include modern digital modes like WSPR, WSJT, FT8, and FT4. They also explore computer-based operations such as Echolink, fostering a dedicated Single Board Computer (SBC) and Raspberry Pi group. Monthly VE testing sessions for Technician, General, and Extra Class licenses are conducted by Ray Vasquez, K4RMV. Meetings are held on the third Tuesday of each month, typically lasting two hours, with a business segment followed by a technical presentation. These gatherings occur in-person at IHop in Mesa, AZ, and concurrently via Zoom, accommodating both local members and winter visitors. Informal chat groups often form post-meeting to discuss specialized topics like D-STAR, SDR, APRS, MESH, and Fusion.

The simple balcony vertical HF antenna made with plastic fishing pole. Just along the pole I install copper wire in 7 meter length. Then was installed ATU. It was used home brew tuner. For each band was used one counterpoise in length 0.8 x lambda/4

The purpose of this construction is to enable the realization of an HF antenna called W3DZZ with minimal equipment and low cost. It allows traffic on the bands 3.5 / 7/14/21 and 28MHz.

This article presents a comprehensive guide to constructing a multiband vertical wire antenna. The design features parallel wires for various bands, all connected to a single balun, ensuring ease of assembly and adjustment. Materials required include a fishing rod, PVC tubing, and inexpensive wire. The antenna is lightweight, cost-effective, and suitable for field use or as an additional home setup. Detailed instructions and diagrams are provided to facilitate successful construction and optimal performance across multiple frequencies.

The BikeLoop antenna project details the construction of a double magnetic loop antenna optimized for VLF frequencies, specifically around 136 kHz. This innovative design incorporates two orthogonal loops, which significantly enhance reception capabilities. Key construction hints include utilizing lightweight bicycle rims for the antenna structure, making it easy to transport and set up in various locations. The document provides valuable mathematical and electrical insights into the antenna's performance, alongside practical reception tests conducted in the Italian Alps, showcasing its effectiveness in capturing various VLF signals, including Sferics and FSK transmissions. Proper setup is crucial for optimal performance. The project emphasizes the importance of grounding and avoiding interference from nearby electrical sources. The reception tests revealed the antenna's ability to capture a range of signals, demonstrating its practical application for enthusiasts interested in VLF reception and antenna experimentation. Overall, the BikeLoop serves as an excellent starting point for those looking to explore the world of VLF frequencies and enhance their antenna-building skills.

The DIY 137 MHz WX SAT V-dipole antenna project details the construction of a specialized antenna for receiving weather satellite transmissions. It provides specific dimensions for the dipole elements, designed for optimal reception around the 137 MHz band, which is commonly used by NOAA and Meteor weather satellites. The resource outlines the materials required, such as aluminum tubing for elements and PVC for the support structure, along with the necessary coaxial cable and connectors. The article presents a clear, step-by-step assembly process, including how to form the V-shape and connect the feedline. It emphasizes practical considerations for mounting and weatherproofing the antenna for outdoor deployment. The design focuses on simplicity and effectiveness for amateur radio operators interested in satellite imagery. Key aspects include the precise angle of the V-dipole and the lengths of the radiating elements, which are critical for achieving the desired circular polarization response for satellite signals. The resource includes photographic documentation of the construction phases and the final mounted antenna.

The Terminated End Fed Vee Antenna (TEFV) is a travelling wave antenna with constant current distribution. Unlike traditional resonant antennas, TEFV operates without standing waves, using a terminating resistor for broadband efficiency. With a combination of vertical and horizontal polarization, it offers wide bandwidth from 1.8 MHz to 30 MHz, eliminating the need for a tuner. Key components include a 9:1 unun transformer and a 500-ohm terminating resistor. Grounding and counterpoise enhance performance, and it can handle power losses of up to 30%. TEFV provides an effective, versatile antenna solution for amateur radio and broadcast applications.

Documents S21RC's construction of an impedance transformer harness for a VHF/UHF cross yagi, utilizing 20m of _RG179_ cable. Details the creation of a DIY RF sampler with a -50dB sampling output, primarily for measuring HF radio PA section output with a Spectrum Analyzer, also applicable for _Pure Signal_ transmission. Chronicles the deployment of a 200m long beverage antenna for the _S21DX IOTA_ operation in 2022, positioned 2m above ground. Discusses the construction of a 3-element short beam for 10m to replace a previous 2-element antenna, with assistance from S21DW. Provides guidance on operating cheap _PA-70_ and _PA-100_ type Chinese SSPAs using IRF530 MOSFETs, emphasizing the necessity of a final LPF. Outlines the design and construction of a fully isolated interface for radio-to-computer connections, supporting various digital modes with isolated ground, audio transformers for IN/OUT, optical isolation for CAT/CIV, and isolated PTT/COS lines. Includes a log of software updates, such as the _HMI/TFT for NX8048K070_ and _2.1.14 Lite_ release with bug fixes for PEP hold and gradual watt decay.

This page delves into the Inverted V antenna, a source of myths among ham radio operators. The author explores the behavior of this antenna type with a focus on a 20m half-wave dipole positioned 10m above the ground. From Pythagoras to high school math, the article simplifies the calculation of dimensions and angles for setting up an Inverted V antenna. It includes a spreadsheet for calculating hypotenuse length and angles, crucial for antenna setup. Additionally, it provides insight into the radiation pattern of a 'flat' half-wave dipole at 10m height. Useful for hams planning to optimize their antenna setup. In Norwegian.

Although most Preselectors are designed with an internal T/R relay, theoretically enabling direct insertion between the transceiver and the antenna, there is a problem when running CW, especially when running full QSK. The switching time of the internal relay is too slow to follow full QSK. The best way to avoid this problem altogether is to insert the Preselector directly into the transceiver’s RX antenna line, thus avoiding entirely the need to switch the Preselector in and out.

A short 3 element LFA Yagi for 50MHz with a 1.94M boom. This antenna has been designed in order to minimise the upward and downward lobes typically seen the the EL plane on Yagi antennas.

Over 500 different types of high-performance electronic cables are manufactured by Alpha Wire, catering to demanding industrial and commercial applications. Their product lines include the robust _XTRA GUARD_ series, designed for harsh environments, and a range of flexible coaxial cables optimized for signal integrity. These cables are critical components in amateur radio shacks, industrial control systems, and data communication networks, ensuring reliable power and signal transmission. The company provides extensive technical resources, including detailed product specifications, application notes, and RoHS certificates, accessible through their online resource center. Hams often utilize their wire and cable products for antenna construction, station wiring, and various DIY projects requiring durable and reliable conductors. Alpha Wire also offers tools like size guides and competitor cross-references, simplifying product selection. They emphasize continuous uptime solutions, reflecting their focus on quality and durability.

Presents various amateur radio topics through blog posts, detailing operational experiences and technical insights from the perspective of SV2YC. The content frequently discusses antenna projects, such as a **portable 20m/40m dipole** designed for rapid deployment, and explores the performance characteristics of different wire configurations in varied field conditions. Observations on propagation and band activity across the HF spectrum are also regularly documented, providing practical context for fellow operators. Specific entries often include detailed accounts of **DX contacts** and participation in minor contests, outlining station setup, power levels, and antenna choices. The blog also covers modifications to commercial transceivers and homebrew accessory construction, offering practical advice on improving station efficiency and functionality. Further posts delve into software applications for logging and digital modes, sharing configurations and operational tips for maximizing their utility in daily amateur radio activities.

Experiments on vertical antennas for HF bands.

A cavity backed antenna is a practical slot antenna tipically used in microwave applications

256 memories enable the _AT-AUTO_ to recall settings across multiple bands, making it efficient for operators who frequently change frequencies. The tuner is compatible with various antennas and amplifiers, such as the Mercury LUX, and integrates seamlessly with radios like the FLEX 6400 using an RS232-USB connection. This integration allows the tuner to follow frequency changes without additional input, enhancing operational efficiency. Despite being out of production, the _AT-AUTO_ remains supported by Kessler Engineering, which offers firmware updates and repair services. The tuner features a cross-needle SWR meter, providing quick visual feedback during tuning. It also includes a QRO keyline circuit to protect amplifiers during tuning. Users appreciate the tuner's ability to track radios via CAT control, avoiding automatic tuning during QSOs, a common issue with other models. The _AT-AUTO_ is praised for its durability and performance, with many users noting its reliability over years of use. Its ability to handle legal limit power and its balanced line output make it a versatile choice for serious operators. Although it lacks some features like multiple coax outputs found in other models, its robust build and continued support make it a valuable tool for HF enthusiasts.

This PDF document provides a detailed guide on designing an 80m loop antenna. The content covers the construction, setup, and tuning of the loop antenna, offering practical tips and considerations for optimal performance. Whether you are a beginner looking to enhance your radio communication capabilities or an experienced operator seeking to improve your antenna system, this resource serves as a valuable reference for building an effective 80m loop antenna.

Enables Android users to operate various _miniVNA_ antenna analyzers via Bluetooth, USB, or Wi-Fi, providing a portable solution for RF measurements. The application supports full control over data acquisition, offering features like custom frequency range selection from 1 KHz to the VNA's full range, and automatic screen adaptation for diverse Android device resolutions. It facilitates intuitive, wizard-based calibration for both reflection and transmission modes, saving calibration data for different VNA types (Standard, Pro, Pro with Extender) to avoid repeated procedures. The software displays critical parameters such as SWR, |Z|, Return Loss, Phase, Rs, and |Xs| on 2-axis graphs or Smith charts, with multi-touch gestures for zoom and frequency shift. It includes a frequency generator mode with independent channels and attenuator control for the miniVNA Pro, along with a sweeper function. The cable data mode automatically calculates phase and loss, measures cable length from less than 1 meter to hundreds of meters, and includes a table of common coax cable velocity factors. An experimental X-tal mode measures resonance frequency, Rs, and Q. Data export options include CSV, ZPLOT, and S1P formats, with CSV import capability. The application also features an SM6ENG Audio mode for SWR tuning without visual reference and provides a miniVNA battery voltage indicator. It supports a wide frequency range, with the miniVNA Extender extending coverage up to **1500 MHz**. The application is compatible with Android version 2.2 and later, tested on devices like the _Galaxy TAB 7.7 P6800_.

The "DIY Telescopic-V Antenna £35" project showcases the creation of a budget-friendly, portable telescopic V-shaped antenna inspired by commercial designs. Using eBay-sourced telescopic whips and custom mounting solutions, the author documents their process, testing, and adaptations. Despite challenges like weather and missing tools, the antenna performed well across multiple bands, enabling successful QSOs. Future improvements include exploring loading coils and testing in better locations. The compact design offers versatility for amateur radio enthusiasts seeking an affordable and practical solution.

Messi & Paoloni offers a range of RF coaxial cables, including the _Ultraflex_ series, specifically engineered for amateur radio applications. These cables feature advanced dielectric materials and high-density braiding, resulting in significantly reduced attenuation across HF, VHF, and UHF bands. For instance, the Ultraflex 7 exhibits a loss of only **2.5 dB per 100 feet** at 144 MHz, making it suitable for demanding DX and contesting operations. The company's product line also includes specialized connectors, such as N-type and PL-259, designed to maintain optimal impedance matching and minimize signal reflections. Each connector is precision-machined to ensure a secure, weather-resistant termination, crucial for outdoor antenna installations and long-term reliability. Messi & Paoloni emphasizes rigorous quality control, with all cables undergoing testing to ensure consistent performance and durability, supporting effective two-way radio communication.

Constructing a dual-band antenna for 40 and 20 meters often involves compromises in size or complexity. This resource presents a compact _open sleeve dipole_ design that addresses these challenges by using 450-ohm ladder line and folded elements to achieve a total length of approximately **17.17 meters**, significantly shorter than a full-size 40-meter dipole. The design leverages electromagnetic coupling, where a primary radiator handles the 40-meter band, and a second conductor resonates on 20 meters without direct electrical connection. This configuration eliminates the need for traditional traps, loading coils, or switching components, simplifying construction and reducing potential loss points. The antenna is fed with RG-58C/U coaxial cable, and a common-mode choke is recommended at the feed point to suppress sheath currents, ensuring a cleaner radiation pattern and minimizing RF in the shack. The design is well-suited for portable operations, field deployments, temporary installations, and restricted urban environments where space is a premium, offering solid performance on both HF bands.

Mitigating impulse-type noise, a common challenge in the **HF radio spectrum**, often requires specialized processing before the signal reaches the transceiver's receiver stages. The NR-1 addresses this by functioning as an RF interference removal device, specifically a noise blanker, targeting transient noise sources. Its operational range extends from 1.6 MHz to beyond 70 MHz, making it suitable for various amateur radio bands and general shortwave listening applications. Unlike QRM eliminators or X-phasers, the NR-1 does not require a separate noise antenna for its operation, simplifying its integration into existing station setups. The device's design focuses on wideband performance, allowing its use both within and outside the allocated amateur radio frequencies. Documentation detailing its operation is available, providing insights into its technical specifications and deployment. This unit is a hardware product, conceptualized and implemented by SV3ORA.

Building A Full-Wave Quad Loop Antenna for 6 Meters. This is an easy antenna to build and the materials cost about $15-20. It exhibits 1.8dB gain over a 1/2-wave dipole. Using an open-wire parallel feedline (commonly called ladder line) with an antenna tuner, it tunes up on the 10m band as a 5/8-wave loop as well

PRO-LINK specializes in the manufacturing and distribution of high-quality cabling solutions, including a wide array of fiber optic cables and various coaxial cable types. Their product line encompasses 50-ohm and 75-ohm coaxial cables, essential for diverse RF applications, alongside specialized RF cables and 10Base-T networking cables. The company also provides a selection of connectors and custom cable harnesses, catering to specific installation requirements. Since 1988, PRO-LINK has offered a 5-year warranty on its products, underscoring a commitment to durability and performance. The product catalog details specifications for different cable constructions, such as _RG-58_, _RG-213_, and _LMR-400_ equivalents, which are commonly used in amateur radio installations for antenna feedlines and inter-component connections. Their offerings support both commercial and amateur radio operators seeking reliable signal transmission. The company's focus on robust cable and connector solutions addresses the critical need for low-loss transmission lines in radio communication systems, ensuring signal integrity across various frequency bands.

A review of the GAP Challenger DX Antenna that is not a traditional 1/4 wave vertical, but is a vertical dipole, this gives it several advantages over a standard 1/4 wave vertical, mainly the reduced number of radials, with excellent performances.

A dedicaed vertical antenna for 80 meters band based on a 40 meter vertical experiment

A 60-foot available space, for example, might necessitate a shortened multiband dipole array to cover 80, 40, and 15 meters effectively. This resource details the construction of such an antenna, combining full-size and coil-loaded dipoles on a single feedline. It addresses the common challenge of fitting multiple HF bands into restricted physical footprints, providing practical guidance for hams with smaller backyards or portable operations. The core of the offering is an interactive calculator that determines required loading coil inductance and dipole lengths for various amateur bands from 160m to 10m. Users input their available space, and the tool provides dimensions, coil turns, and an efficiency rating (Good or Fair) based on the antenna's electrical length relative to a quarter-wavelength. It also suggests suitable _PVC_ pipe diameters for coil forms. The article further illustrates a center feed-point assembly using an 18-inch section of 2-inch _PVC_ pipe, detailing eye-bolt spacing and coaxial connector installation. It emphasizes the importance of adequate spacing between parallel dipoles and offers customization options for the feed-point, including the addition of a _Balun_ for improved feedline isolation.

The Black River Amateur Radio Club (K8BRC) operates as a central hub for amateur radio enthusiasts within Van Buren County, Michigan, and its adjacent regions. This organization facilitates various activities, including local nets, educational initiatives, and community service events, all aimed at promoting the hobby and enhancing operational skills among its members. The club's focus on local engagement ensures a strong sense of camaraderie and mutual support among hams, from those just earning their _Technician_ license to seasoned DXers. Members frequently participate in field operations and emergency communications drills, applying practical skills in real-world scenarios. The club also maintains resources for new operators, offering guidance on station setup, antenna theory, and operating procedures. Their commitment to public service is evident through participation in events requiring reliable communication. K8BRC provides a platform for hams to share knowledge, collaborate on projects, and engage in on-air activities, strengthening the local amateur radio community. Many members have achieved **100** DXCC entities.

Microwaves101 provides an extensive repository of information covering fundamental principles of microwave design, targeting engineers and radio amateurs interested in the higher frequency spectrum. The site features a detailed _encyclopedia_ of microwave terms and concepts, alongside practical design considerations for various components and systems. It serves as a foundational reference for understanding RF propagation, transmission lines, and active/passive microwave circuits. The resource includes numerous calculators for impedance matching, filter design, and other critical RF parameters, facilitating hands-on project development. Discussions on **10 GHz** equipment and **24 GHz** projects highlight practical amateur radio applications, extending to operations up to 134 GHz. Content spans from basic theory to advanced topics like MMIC design and antenna characteristics, supporting both educational and practical endeavors in microwave technology.

This article provides a detailed guide on how to build a no holes roof mount for ham radio antennas. The author shares their design that can hold 2 masts and offers tips on installation. The mount is versatile and can handle small 144 Mhz or 432 Mhz beams, as well as small verticals. With adjustable angles and spacing, the mount can be customized to fit different roof types. Additionally, the author suggests affordable options for obtaining Dish antenna mounts. Overall, this DIY project offers a cost-effective solution for ham radio operators looking to mount antennas on their roofs.

A vertical antenna for 160 meters band based on the K6MM vertical with some enhancements and modifications on the main capacitance hat

A light portable 2 element Delta beam antenna for 14 MHz. It is basically a two element delta loop wire antenna made for portable usage providing good directivity and a 4.2 dBd gain

This is a very small vertical 160m antenna that fits in the loft of even my small house. It was built as a way of getting a signal out on 160m for local AM contacts, but the local noise level was far too high to allow it to be used at night for this purpose. However, on WSPR it did a pretty good job with WSPR spots from a very long way across Europe being received when running 2.5W out.

10 Elements Cross-Yagi Antenna for 433 MHz. The base of the 10el antenna is the recalculated RA6FOO antenna.Circular polarization is realized - by a phasing quarter-wave line, matching of horizontal and vertical polarization antennas

The Narrabeen JOTA and JOTI camp facilitates global communication for Sydney North Region Scouts and Northern Sydney Girl Guides, utilizing amateur radio and internet technologies. Participants engage in two-way radio contacts, often on **HF** bands, to connect with other scouting and guiding groups worldwide, fostering international goodwill and technical skill development. The event integrates both traditional **ham radio** operations and modern internet-based communication methods, providing a diverse experience for youth members. The resource outlines the specific activities undertaken at the Narrabeen site, including station setup, operating procedures, and the use of digital modes for JOTI. It highlights the educational aspects of the event, such as learning about radio propagation, antenna theory, and basic electronics, all within a structured camp environment. The page also provides logistical information relevant to the Australian context of the event.

Tysonpower details a DIY AZ/EL antenna rotator project designed for under €150, inspired by the Satnogs Tracker. Constructed with 2020 aluminum extrusion and NEMA23 stepper motors, the rotator is controlled via an Arduino Nano. It effectively tracks smaller antennas like Yagi, though struggles with heavier dishes. STL files are available on Thingiverse.

On the field comparison among C-Pole antenna, an EFHW vertical antenna and an Inverter V dipole antenna. Test is done using two identical WSPRLite beacons that transmit with 200mW on the WSPR frequency and analyzing spotted results.

Dipole antennas, vertical half-wave dipole antennas with impedence tranformes that can be used for portable operations. Some well worn antenna configurations are the easiest and loudest lash-ups you can try.

The collinear J-Pole, often known as the Super-J, does improve the behavior over a regular J-Pole. there is an advantage when vertically combining 1/2 radiating sections to have a bit of separation between the half-wave end points. Get 0.8 dB more gain out of the trusty Super-J by replacing the traditional phasing stub with a long coil.

This unique online tool helps Ham Radio operators to choose the right rotator for medium and large HF antenna systems. The algorithm implemented in this calculator is the result of 40 years of experience in the HF Antenna sector. Given the Wind Speed, the total antenna square area, and the boom length, it will return the calculated torque value.

This Field Day Vertical Antenna project is the result of many years of attending various field day sites and realizing that what was needed is a simple, easy to assemble vertical antenna. The design of this Field Day Antenna is not very novel and leverages ideas from Butternut verticals and ARRL publications. The one essential requirement was that the antenna can be raised by just one person. The design of this Field Day Antenna is an above ground mounted ground plane vertical.

Vertical end fed antenna used for portable operations. The antenna will work on 80 with acceptable results, it will work fine on 40m, and it will be a good deal better than a normal 1/4 wave GP on 20, 17, 15 meters.

Author found a ratio between the lengths of the sides of the Delta Loop that give reasonably low SWR into a 50 ohm coaxial cable almost independent of the high above ground and other surroundings. This ratio also gives good results no matter orientation. Includes an online delta loop antenna calculator.

This antenna just requires about 24m of free space instead of 41m that a normal half wave 80m antenna needs to hang up. The so called loaded dipole uses a coil in every dipole arm to electrically lengthen the mechanical too short dipole arms. Every coil has an inductivity of 120 microHenry.

Crossband Repeating is a process where a Ham transmits one signal on one band (typically UHF), and it is received by another radio with a better antenna/power installation, and re-transmitted (typically on VHF) to another radio system, or a repeater. Everyday examples of cross-band repeaters are repeater receive sites that hear the input signals on 2m and retransmit those signals on a frequency higher than 220 MHz.