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An home made remote antenna tuner project that with a 6 meter random wire and two radials of about the same length, can tune from 40 to 10 meters without any issue.

This simple antenna was installed on the attic. Antenna was matched with help an Automatic ATU in 40, 30, 20, 17, 15, 12 and 10 meter amateur Bands. The Antenna worked satisfactory on the above mentioned bands.

A folded dipole is an antenna, with two conductors connected on both sides, and folded to form a cylindrical closed shape, to which feed is given at the center.

A home made portable vertical antenna, that with a single 1/4 wave counterpoise wire is possible to achieve less than 1.5:1 SWR on 40, 30, and 20 meter bands. It is basically a center load, shortened ground plain vertical antenna.

A free Labview antenna calculator program. This interesting calculator for small loop antennas can be ran on most recent Windows versions using the Labview runtime.

Article on 50 Mhz Yagi Antennas stacking by OH1ZAA/NN0Y

A trap antenna dipole covering two differen bands made reusing an old 160/80m inverted vee antenna.

A 3.2m EME dish project that provides a better performance on 1296 MHz (10+dB sun noise vs. 6dB with my 432 array) and an even better performance on 2304 MHz

Antenna may be made practically from any wire (strand, solid) having a reasonable diameter 0.5 2.0 mm (24- 12 AWG). Antenna may be installed at any balcony of 3 to 6 meter length.

Presents _Beam Quest_, the official Japanese distributor for _SteppIR_ antennas, detailing their product lineup and services. The site showcases various _SteppIR_ Yagi models, including the _Dream Beam_ series (DB42, DB36, DB18E, DB11) with configurations from two to four elements, alongside the _Big IR_ and _Small IR_ vertical antennas. It also lists accessories such as TX/RX and PC interfaces, essential for integrating these advanced antenna systems into a ham shack. Operators often seek out _SteppIR_ antennas for their dynamically adjustable element lengths, which allow for optimization across multiple bands, a significant advantage for DXing and contesting. This adaptability contrasts sharply with fixed-element Yagis, providing a distinct edge in varying band conditions. The resource provides contact information, including email and phone numbers, for inquiries and support regarding _SteppIR_ products within Japan, serving as a direct point of contact for sales and technical assistance.

When a broadcast antenna is to be placed on top of a building, there are special problems of feeding and grounding. The radiator is usually electrically short, that is, much less than one-quarter wavelength high.

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

This project details the construction and testing of a M0PLK Delta Loop antenna for the 20-10m ham radio bands. Inspired by positive reviews highlighting its reduced local QRM compared to Cobweb antennas, the author built the antenna using aluminum tubes, DX-Wire FS2 wire, and a 1:4 balun. A mix of custom 3D-printed parts and careful assembly ensured stability and performance. Initial VSWR measurements met expectations, and test QSOs demonstrated success across multiple bands. Future enhancements include adding a lightweight, remote-controlled rotator for directional capabilities.

A loop antenna for 80 and 40 meters band, the main loop is based by a crossed line using aluminium strip lines. The main loop diameter is 150 cm.

Measuring noise fiugre on the W2IMU horn and the dual-dipole-feed

Founded in 1990, Nearson, Inc. has been providing our customers with exceptional value with the products and services we offer. VHF, UHF mobile radios, Cellular, PCS equipments as well as ISM band wireless data and WLAN applications.

An article describing basic concepts of antenna radiation, and in particular directional antennas like Yagi antennas or Quad antennas and how they determine the direction or signals.

A modified Hairpin antenna for a wider bandwidth an mounted on a grounded metalic mast

NEC models are used to explore the GR5V and ZS8BKW optimizations. A third optimization is also rediscovered. The effect of fixed lengths of 75 ohm coax are explored. A link to the NEC model is provided.

An home made antenna switch with a Dummy Load selector. If you forget the radio is connected to the open or grounded side of the switch and you try to transmit, it is very easy to damage the finals of your transceiver.

The wire antenna described in this page provides much stronger signal strength while staying within the concept of a dummy load antenna.

Why build antennas out of copper and not aluminum or stainless steel. Selecting the best metals for antennas evaluating the conductivity factor.

Online HB9CV antenna calculator, accept as input the desired resonating frequency and provides dimensions for spacing and length of each element, including boom and radiator diameter.

Over 100 distinct RF connector types are available from AIR802, including popular UHF series PL-259 plugs and SO-239 sockets, designed for a wide array of coaxial cable dimensions. The company specializes in producing connectors compatible with common amateur radio cables like RG-8, RG-213, and RG-58, ensuring reliable signal integrity for antenna systems and shack interconnections. Their product line extends to various coaxial cable types and pre-made antenna cable assemblies, offering ready-to-deploy solutions for hams. AIR802 also provides custom cable assemblies and pigtails, catering to specific installation requirements for transceivers, tuners, and amplifiers. These pre-fabricated options simplify station setup, reducing the need for field termination of connectors. Michael Bryant is the contact for inquiries regarding their range of RF components, which are essential for building robust and efficient amateur radio stations.

Benefits of stacking two HF antennas vertically

Have you measured the SWR at the antenna?

This is a standard calculation method that can help you while tuning dipole antennas, by adjusting wire lengths. This method can be used also when you need to add lenght to your wires, and can be additionally used to quarter waves vertical antennas

This DIY vertical multi-band Windom antenna offers a practical and effective solution for amateur radio enthusiasts seeking a versatile and compact antenna for HF communications. Its simplicity of construction, multi-band capability, and favorable performance make it a valuable addition to any radio shack. The article provides detailed instructions on constructing the antenna and balun, along with diagrams and component specifications. Field tests demonstrated successful contacts with stations across Europe and North America on 14, 18, and 28 MHz. The antenna exhibited comparable performance to a W3DZZ dipole and outperformed a Cobweb antenna on 18 MHz. Low noise levels were observed, effectively suppressing background noise.

The antenna described in this article is for 50 MHz, but the design can be scaled for any band, including VHF, UHF, or even the higher HF bands. The antenna is nothing more than a square loop of wire, approximately 30" (or ~76cm) per side. The loop is fed in the middle of one side, and the opposite side to the feed point has a gap in it.

A home made magnetic loop for HF Bands. This small and compact loop is designed to support small power transmissions on HF bands, from 7 MHz to 21 MHz

A 70 cm yagi antenna design by YU7EF includes tables with antenna elements dimension and spacing. This UHF Yagi antenna plan provides a maximum gain of 17.93 db

A fand dipole antenna home made for the 7,14,50 MHz. This article descbribes how to homebrew the antenna, hot to setup and some SWR measurements.

This antenna is an off-center fed spiral dipole for 40 meters. The spiral dipole is very compact, making it well-suited for limited space (like an apartment patio), while the off-center feed gives the antenna some multiband capability.

An experimental antenna for HF reception. It consists of a single loop element mounted on the ground. It is stealthy, small, and quiet. EZ-NEC plots and on-air test results are included.

Article descrive the different types including coax and open-wire feeder and waveguide.

The Magloop Antenna Calculator was developed to predict the characteritics of a small-loop (aka magloop) antenna, given physical dimensions entered via slider widgets. This magnetic loop antenna calculator works also on most mobile devices, adjusting sliders and calculating dimensions in real time.

The OCFD Off-Center-Fed Dipole Antenna is an excellent multiband antenna that is relatively simple to construct, yet gets quite decent performance.

Cubical Quad Antenna On-line Calculator helps on defining the size of each element and spreader. Simply give the resonating frequency and it will calculate size of each element.

Modifying an MFJ-259B Antenna Analyzer to operate on 630 meters

Active Receiving Antennas, designed for reception of shortwave, mediumwave and longwave signals and VHF/UHF signals

A comparison of commercial 4m verticals by by Ian Hogan G6TGO

Modified 80cm Offset Dish for 2.4 GHz Satellite Reception. This 50-ohm impedance antenna allows, when connected to 2.4GHz preamplifier and downconverter, to receive Amateur satellites with 2.4GHz transponders such as AO-40.

A simple portable dipole antenna for the 40 meter band using a total lenght of 18 meter. It can be used for 80 to 10 meters coverage using a antenna tuner.

An experimento of a 40 meter delta loop antenna both in horizontal and vertical polarization and several elevation angles with interesting notes about the effect of the radial field under the antenna.

K2KW notes on verticals antennas

Active antennas can be very useful, in particular they can help reduce local electrical noise by allowing the antenna to be installed in a corner of the garden well away from house wiring. The original PA0RDT antenna uses a very small patch for the antenna and relies on the antenna being installed quite high.

This Guide helps you to build the 1:2 BalUn 600 Watts DIY kit step by step. If a delta-loop or quad-loop antenna is powered with a coax cable from the transceiver it is necessary to use a 1:2 BalUn. This 1:2 BalUn uses a symmetrical 1:2 impedance transformer.

If your antenna is fixed in one direction, you will notice that your antenna works perfectly only during fall and spring.

Available worldwide can be used as Arduino Shield or plug it in to you PC , or with a bluetooth adapter connect to Android. With a highly optimized software, KAI200 brings you: a. Antenna analyzer form 1 up to 200 Mhz; b. WSPR transmiter (set up by serial terminal); c. Square Wave Signal generator KAI200 is all you need for your radio whatever it is Yaesu, Icom, Kenwood or Drake and DIY projects.

Maker of small and compact multiband QRP UltraLight Magnetic Loop Antennas and UnUn transformer for end-fed multiband antennas