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Relevance of a proper ground systems on short HF vertical antennas, with an analysis on a vertical antenna for 160 meter band

An inverted V Dipole antenna for HF bands, working on 10 20 40 and 80 meters band. PDF Presentation

A summary, overview or tutorial covering the basics of Meteor Scatter or Meteor Burst Communications, a form of radio signal propagation often used at VHF.

Simulation of a top loaded vertical antenna for 1.2 MHz

A great and efficient monoband VHF portable antenna. The article consist of two version of a 12.5 Ohm 3 elements yagi beam antenna plans for the two meter band, a full sized and a shortened version expecially designed for the SSB and CW on 144 MHz.

A trapped multi band end-fed-half-wave antenna for 40/30/20/17/15m.

The receiving antenna setup for the top band, made with a 9 elements vertical antenna array, remote controller and remote relais.

The Horn reflector antenna at Bell Telephone Laboratories

An antenna for 80 meters band for those who does not have enough space to setup a halwave wire dipole that is aprox 130ft or 40 meters. The antenna is an open-wire-fed shortened dipole

The webpage discusses metal fatigue in antenna elements for radio amateurs, offering construction tips and techniques. It covers theory, tricks, and the use of baluns and coils.

Utility-Driven Tradeoff Analysis, if you want to geto on the microwave bands , you will have to choose the proper antenna for your operating conditions. How to decide is not always easy, and you may also decide to build your own antenna.

Presents field test results for an **elevated SuperAntenna MP-1** portable antenna, configured on a tripod for HF operations. The resource details the antenna's setup and performance during a portable activation, focusing on its use across the 40-meter, 20-meter, and 17-meter amateur bands. It includes observations on signal reports and operational considerations for this specific portable antenna configuration. The content provides practical insights into deploying the MP-1 antenna in a non-ground-mounted setup, which is often a point of interest for portable and QRP operators. It documents the author's experience with the antenna's tuning and effectiveness for making contacts under real-world conditions, offering a user-perspective review of its capabilities. The article also features photographic evidence of the antenna's deployment, illustrating the tripod mounting and the overall portable station setup.

Observing how fractal antennas might exhibit characteristics that are correlated to their form by kb7qhc

Near Vertical Incidence Skywave propagation is a form of radio wave propagation used on the MF and HF bands to provide radio communications and broadcasting coverage over short distances, especially where the terrain contains obstacles.

It is possible to detune the tower so that, at least on one band, the tower can be made to effectively disappear. That is, become non-resonant on the band of interest. This allows the vertically-polarized low-bands antenna to meet its potential.

The MFJ-971 portable antenna tuner, as stock, lacks a bypass switch and sufficient inductance for efficient 1.8 MHz operation. This modification addresses these limitations by integrating a DPDT switch for direct signal bypass, enhancing operational flexibility. Furthermore, the guide details the addition of a T130-2 iron powder toroid, wound with **29 turns** of enamelled copper wire, to augment the tuner's internal inductance. This increases the maximum inductance from approximately 17µH to around **27µH**, enabling effective impedance matching on the _160-meter band_. The modification involves cutting the wire after the 'L' tap on the original inductor and inserting the additional toroid, ensuring the entire original coil plus the new inductance is engaged when 'L' is selected. This preserves the functionality of other inductance settings while extending low-band performance. The article also highlights a potential RF burn hazard from the variable capacitor nuts on the MFJ-971, even at QRP power levels.

6 Meter J-Pole from 450 Ohm Ladder Line a quickie project

The Japanese-made Maldol MFB-300 HF vertical antenna offer extremely wide-band performance, with a specified frequency range of 1.0-60 MHz.

Experimenting a 20 40 meter short coil loaded dipole antenna with the goal to keep the total length under 40 feet so that the dipole can be mounted on two 20 foot fiberglass pole to make a 20/40 meter rotatable dipole.

A classic document originally presented in Proceedings of the Institute of Radio Engineers in 1937 and is, still today, the standard referenced by the FCC, text books and many amateur radio publications.

Article on Yagi and Log periodic antennas by Tom, K1JJ

An interesting guide to aerials comparing height, gain and angles

About antenna or aerial resonance and bandwidth and the impact of RF antenna resonance and bandwidth on radio communications systems.

A multiband J-Pole antenna project that cover 144,220 and 430 MHz. The articles includes several pictures of this multi-band antenna, including handmade schematics and diagrams, project is mainly in Italian

This air-powered Tennis Ball launcher is designed to launch tennis balls over trees towing fishing line.

This antenna is an omnidirectional and multiband and it is well suited for DX enthusiasts with limited space. Each of the parallel circuits (trap) behaves like an isolator on its resonant frequency.

Demonstrates the community-driven mission of the McKinney Amateur Radio Club (MARC), a North Texas organization dedicated to advancing amateur radio. The club actively promotes continuous learning, encouraging technical innovation among its members, and provides avenues for public service engagement, skill enhancement, and global connectivity with fellow operators. MARC hosts weekly breakfast discussions every Saturday at 7:30 AM at IHOP in McKinney, Texas, covering diverse topics and offering a Q&A forum. The club emphasizes emergency communication preparedness, antenna design and tuning, and the science of global radio wave propagation, crucial for clear amateur radio contacts. Furthermore, MARC explores modern radio technologies, including digital modes and _Software-Defined Radio_ (SDR), blending traditional amateur radio with cutting-edge advancements. The club also facilitates license testing sessions, hands-on training, and participates in events like _Field Day_ to hone emergency communication skills.

A travel, or a fixed vertical coax antenna originally designed by PA0FBK. This antenna is very easy to make from a piece of 50 ohm or 75 ohm coaxial cable, and can be either smooth, roll-up version, or rigid cable

Experiments with Balloon and Kite Lifted Antennas bby G4VGO

A portable wire antenna for the HF bands, made with a common speaker wire. In its natural form, the speaker wire acts as parallel feed line coming up to the bottom of the PVC feed point. From there, it's split into two wires, one heading out each side of the PVC tee.

Article on antenna feed impedance and the importance of matching RF andtennas to feeders, including notes on Radiation resistance, loss resistance, and efficiency are also detailed.

The Maria Maluca HF multiband antenna as designed in 1957 by PY2BBP is a directive antenna for 15 meter and a passive element that works as director and reflector in different bands

This antenna was conceived mainly for high-speed digital transmission via satellite. The antenna is made of two full waves loops , mounted at right angles to each other. Then coupled together, 90 degrees out of phase over a horizontal circular reflector. With this configuration the antenna is omni directional and circularly polarized.

A very well done presentation about End-Fed Half-Wave antennas. This PDF document contains a summary of experiences in how to build custom EFHW antennas. Includes an interesting comparison table of UnUn configurations with recommended toroids, Wire size, turns and capacitors. An useful recap on common errors in building homebrew EFHW Ununs completes the document.

HA8DU European manufacturer of quality amateur radio antenna tuners for HF Bands, from 10 meter to 160 meters band. Products includes manual and automatic antenna tuners, power handling till 3.5 KW. HA8DU produce even custom made variable capacitors and rotary switches.

In this article the author shows the receiving loop antenna for 160 meters band installed at his QTH. Diagram and movie available. Article in in Turkish but can be translated in english

Basic priciples of Yagi antennas and its variations like Quagi antennas, Quad antennas includes pictures, drawings and online calculators by KN9B

The antenna almost repeat the design of the Car Antenna however instead of aluminum tubes it was used copper wire in plastic insulation in diameter of 2- mm (12 AWG).

An antenna system is electrically small if it's enclosing sphere is <&#955;/2&#960;. So a 10m band antenna of under 1.6m long qualifies.

The Homebase-10 is a wire halo antenna for 10m built with DIY store parts, effective despite its small size. Includes a dual-band version for 10m and 6m with gain around 0 to -2dBd, near omnidirectional pattern, and horizontal polarization. Overview based on a 2008 Practical Wireless article.

Flyaway Antenna, Carbon Fiber Antenna,Ku band Aluminum Antenna,Auto-Tracking Flyaway antennas by Probecom Microwave Technology

In this article the author analyze six different type of VHF handheld antennas and as result of his self training on his new vector network analyzer published this interesting report

Basic anctenna theory, general information on antennas

An experimental prototype of an asymmetrical hatted vertical dipole antenna that can work on HF bands 20 to 10 meters band. The AHVD Vertical dipole is an upside-down T design

50 Ohm Coax Antenna Power Splitter and Matching Network

Constructing a multi-band fan dipole for HF operation presents unique challenges, as VE2XIP demonstrates through his 2012 project to replace an existing commercial antenna. He details the process of calculating wire lengths using the 468/frequency formula, emphasizing the critical importance of equal leg lengths for each dipole element. The author shares practical insights gained from building at ground level, noting how elevation impacts resonant frequency and SWR, particularly for lower and higher bands. VE2XIP's experience highlights the iterative nature of antenna tuning, starting with the lowest frequency band (80m) and working upwards. He provides a specific example of trimming calculations and offers a clever tip for accurate wire removal. The article also touches on the mechanical aspects, such as dowel spacing for wire support and the benefits of a pulley system for repeated raising and lowering during the tuning process. Field results showed significant performance gains over the previous Alpha-Delta DX LB Plus, with **20 dB over 9** signal reports on 80m compared to 57. The project cost around **$100** for hardware, proving a cost-effective alternative. The author also discovered a bonus 6m capability and achieved an inverted-V _obtuse angle_ of approximately 115 degrees, contributing to a surprisingly stealthy installation.

Single antenna with multiple polarization for diversity, diveristy receivers and propagation effects on signal polarization

Comprod Communications specializes in the design and manufacturing of RF communication solutions, including a comprehensive range of antennas, duplexers, multicouplers, and combiners. The resource details their product categories, which encompass base station antennas, mobile antennas, transit antennas, and disguised antennas, alongside mounting solutions and in-building systems. It highlights the company's 40-year history in adapting offerings to client needs and anticipating industry trends, emphasizing product durability and low maintenance for harsh environments. The company's offerings are presented as high-quality, designed to withstand extreme conditions from Arctic cold to equatorial heat and humidity. The site mentions solutions and technical sales support, training, and site analysis and system design as part of their service portfolio. It also references being a market leader trusted by over 1,000 customers worldwide, positioning itself as a partner for RF communication needs.

Cmpter Electronics specializes in the design and manufacturing of RF coaxial connectors, RF adapters, and RF cable assemblies, serving diverse applications across datacom/telecom, automotive, instrumentation, aerospace, and defense sectors. Their product line includes RF coaxial terminations, attenuators, and waveguide to coax adapters, catering to specific needs in radio frequency systems. The company also offers precision adapters and connectors, alongside glass beads and test cable assemblies, indicating a focus on high-quality components for demanding RF environments. Their resource center provides valuable information, including an "RF Made Simple" section and a product catalog for download, which assists engineers and technicians in selecting appropriate components. The product named system helps in identifying specific parts, streamlining the procurement process for complex RF solutions. With a comprehensive range of RF coaxial cables and related tools, Cmpter Electronics positions itself as a key supplier for critical infrastructure requiring reliable signal integrity. Their offerings support a broad spectrum of RF applications, from basic connectivity to advanced test setups.

Living in a no antenna deed restricted community sounds bad for a HAM, but it means you just need to be more creative. I have found this will not stop your DXCC activities and many of my local HAM club members will agree