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The structure of this dual band VHF UHF antenna is very simple. It consists of two identical square loops, whose sides measure a quarter wave, connected together at the ends. A project by I5NZR

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.

Manufacturer of amplifier for small magnetic and electric receiving wideband antennas, and variable delay line kit for active antenna phased arrays

Accessing antennas at great height poses many potential safety hazards. Essentially, climbing ladders or scaling towers, regardless of whether or not a commercial safety harness is fitted, is risky business indeed particularly for those hobbyists in their latter years or not as physically capable as others.

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.

Basic magnetic loop antenna examples and loop aerials theory explained. This article inclued some interesting tricks on building magnetic loop antennas and an usefull excell sheet to help compute magneti loop antennas calculating power efficiency from 10 to 40 meters band

A small, easy to build, copper tube magnetic loop antenna for the 2 meters band. In Italian

When on the trail, at Field Day, or whenever a good antenna is unavailable, a random wire can save the day, but it is important to understand its properties.

Thsi article describes a microcontroller driven semi-automatic antenna tuner capable of handling power levels up to 150 watts. The device is a low pass filter tuner manually tuned by setting the optimized L/C combination by hand and then storing the values into the EEPROM of the mictrocontroller to recall them later (seperately for each band from 80 to 10 meters including WARC bands)

The problem with making your own trapped HF antennas is usually getting the coaxial traps tuned to frequency. This article explains a method using a RF signal generator at +10dBm output into the coaxial trap.

An interesting article on end fed half-wave wire antennas with a couple of original experiments. Author illustrate the role of the QRP matchbox, and a 40/20 meter antenna with a center stub making it a large bandwidth antenna for 40 and 20. Includes also an 80/40 end fed with the typical coil to make it available on 80 merts band.

This magnetic loop DIY site is ment to be an introduction into making DX high quality magnetic loop antennas that will beat any dipole

A Multiband Slinky Coil for the PAC-12 portable Antenna, can be used also as a dual PAC-12 dipole by James Bennett

Antennas for the 1296 MHz based on the construction plans of some Yagis 35 elements by DL6WU, F9FT, DJ9YW. These antennas features a boom of about 3 m and gives a gain of about 17.8 dBd

A small antenna for 50 MHz made with copper cable loading coils

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.

There are quite a few variants of the design accompanied with many opinions on the effectiveness of the antenna. This page features links to some similar projects and a homebrewed personalized version of this portable antenna tuner

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.

Dipole antennas are some of the simplest antennas to build in addition to being very efficient and solid performers. I wanted to make a simple dipole antenna for QRP portable operation that could be used on multiple bands.

Make them simple then Make them work. The LAZY H antenna is a general type of antenna that is in the curtain array family. By placing two 1 wavelength dipoles in a plane that is at right angles to the direction of maximum radiation and keeping the proper in-phase current condition to each element, you can achieve a high gain bi-directional antenna.

A dual band vertical antenna for 160 and 80 meters band, on a 18m spiderbeam fiberglass pole. This vertical is a good compromise when you want good performance on these two low ham bands and don't have the space to install two seperate antennas.

A homemade j-pole antenna for six meters band, designed to work on local repeaters, and working on the 52-53 MHz. Includes a list of needed materials and detailed description on assembling the copper tubes used to build this antenna.

Description and online calculator for Log Periodic Dipole Arrays LPDA are directional antennas featuring a relatively constant characteristics across a wide frequency range.

An 20 30 40 meters trapped dipole antenna plan for sota and portable operations.

An essential kite antenna plan for the top band, Antenna has been tested at half wave and quarter wave.

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.

The Linked Dipole is a multiband antenna designed for 80/60/40/30/20m bands, optimized for the (tr)uSDX low bands configuration. It incorporates a 1:1 Balun to prevent common mode currents, ensuring balanced operation with coaxial cable. The Balun, wound on an FT140-43 core, achieves 37-40dB attenuation. The design includes a 3D-printable housing for compactness and waterproofing, with labeled link insulators for ease of use. Wire lengths were meticulously adjusted for optimal performance with a 7m pole and 3m rope extension, ensuring the antenna's ends are off the ground for improved behavior. The project includes downloadable printables for DIY construction.

A basic YAGI UDA online antenna calculator, accept as input frequency, number of elements, diameter of parasitic element and boom diameter. This online calculator will generate a basic design data including each element length and spacing.

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 home made end-fed half-wave antenna coupler with antenna lenght calculator and counterpoise calculator based on center frequency. Includes pictures and drawings along to antenna homebrewing instructions with a home made on air wound transformer

No matching adjustments needed. Directly perfect match to 50 Ohms using a remotely switched wideband transformer

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.

Amateur radio loop antenna project using a Comet CVBA-500BC vacuum variable capacitor.

Antenna Analyzer plus 500 is a multifunctional measuring instrument, very useful for amateur radio activity. Its size allows you to easily take it for relocation as well. Frequency range: 100KHz - 500MHz. Access directly via WiFi. Includes a dual-channel signal generator

Introduction to homebrewing antenna, for AM FM band reception

The ARRL's End-Fed Half-Wave (EFHW) Antenna Kit is an easy-to-build four-band antenna designed for 10, 15, 20, and 40 meters. Ideal for portable operations, it includes a 49:1 impedance transformer for compatibility with most transceivers. This project, detailed with step-by-step assembly instructions, involves creating a weatherproof enclosure and impedance matching network. The kit simplifies HF operations and supports multiple configurations, making it a versatile tool for amateur radio opertors.

Top Loaded Vertical Antenna 3,5 MHz 80m and a 14 MHz Trap for the 20m band. The weight of this portable vertical antenna is less than 1 kg, including the ground network. The weight of the telescopic fiberglass fishing rod is another 1kg. The rod expands from 1.5 meters to 8 meters.

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.

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.

Author experiments end fed half wave antennas using common two conductore speaker wire, this article features a couple of end-fed halfwave wires for the 40M and 20M bands.

A Shielded Low Frequency Loop Antenna, allows Simultaneous Transmission and Reception at the Same Site.

Article about the microstrip patch antennas, and in particular the rectangular, single-polarization microstrip antennas, commonly abbreviated MSA.

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.

Four or Five turn one meter loop antenna for 80 and 160 meter band. This home made receive only antena can be assembled in a small place.

Stacking yagi antennas for 50 Mhz band article by by Zaba, OH1ZAA/NN0Y

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

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.

This presentation applies to HF / VHF / UHF antennas and is about 14 different type of antennas suitable for indoor od apartament installations

A collection of 450 MHz Cheap Yagis that have proven great portable operations, back-packing and transmitter hunts, and are something inexpensive you can throw up in the attic for that weak repeater

An end-fed half wave antenna matching unit made of 3:24 turns ratio on a FT140-43 toroid with a 150pF capacitor across the input.