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Ideal for QRP operations on 10 meters band in french

This VHF 145 MHz antenna is easy to build and with no radials. It shows equal gain of 5/8 lambda. It is light weight, you can hang it somewhere (on a tree may be) and work.

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.

KC22TX receiving loop antenna for 160 meter band

Comparison chart between Cushcraft R8, Hy-Gain AV640 , Butternut HF6V, Gap Titan and Eco 7+

Pictures and calculated values for this home made magnetic loop antenna for the 160 meters band by HB9MTN

A moxon antenna for UHF in french

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.

A project of VHF regenerative receiver by VK2ZAY

RF Choke to prevent hf currents on the feedline or...1:1 Choke Balun, sometimes called the "UGLY BALUN"

A simple drawing of a shortened antenna for 40 meters by using a PVC tube

Animated quad and yagi comparison. You can see antennas' characteristics behavior in a vertical plane with changing of the height.

Article on the HF dual band antenna with construction details and how to add 160 meters to the HF2V

List of italian airport frequencies

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

How to make a loading coil for the AD5X portable vertical antenna

Homebrew a vertical antenna for 40 and 80 meters band based on popular HF2V model by DL7JV

A quarter-wave vertical antenna design for HF operation offers a practical solution for radio amateurs seeking a compact and efficient multi-band radiator. This project details the construction of a 5-band HF vertical, drawing inspiration from established commercial products such as the _DX COMMANDER_ and the MV6. The design emphasizes ease of assembly and disassembly, making it suitable for portable operations or installations with limited space. The article provides insights into various construction methods and offers practical tips for building a robust yet lightweight antenna. It highlights the benefits of a vertical configuration for DX contacts, particularly on the lower HF bands, and discusses real-world performance observations. The antenna is designed to cover multiple HF bands, providing versatility for various operating scenarios. Operators can achieve significant DX results with this type of antenna, often comparable to more complex arrays, especially when deployed with an effective ground system. The project aims to empower hams to build a capable antenna without significant financial outlay.

1/2wave vertical antenna for the 6-meterband and a 5/8 ground plane antenna for 50 Mhz

G8ODE schema to reduce a half-size G5RV to 70 ft.

A vertical antenna for the top band, made with a 26m fiberglass spiderpole by DJ0IP

Don't buy or build a semi-vertical trap antenna until you read this article! If you can use a drill, saw and screwdriver this is a simple project.

Homebrew a 2 meter 1/4 wave vertical antenna for the 146 mHz ham radio band

This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

Constructing a compact, two-band magnetic loop antenna for HF operation, especially from constrained locations like a balcony, presents unique challenges. OK1FOU's design, inspired by DJ3RW's 50 MHz loop, addresses these by employing an unusual side-fed configuration and placing the symmetric, two-section variable tuning capacitor at the bottom of the loop, directly connected to the coax shield. The article provides specific material recommendations, including two 1-meter wooden pales and about 3 meters of thick loudspeaker cable, noting the high current (60A at 100W) in the loop. Construction steps detail forming two turns with a 5 cm gap, using a GDO to pre-tune the open loop to a frequency slightly above the desired highest band, and then integrating the tuning and coupling capacitors. For 10/14 MHz, an open loop resonance of 16-17 MHz is suggested. Practical experience with the 10 MHz band from a third-floor balcony in Prague (JO70GC) shows a 1:1 SWR across most of the band without an external ATU. While DX traffic was modest due to the urban environment, QSO examples with RA6WF, LA6GIA, G0NXA, and LZ1QK on 10 MHz are provided, demonstrating its operational capability.

An assortment of Amateur Radio-related technical articles written for the JUG, the newsletter of the Northern California Contest Club. Topics include unique but simple and useful radio modifications and accessories, and rig reviews.

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

A circular waveguide calculator for designing cantennas include source code and windows executable by lincomatic

Introduction to NVIS advantages and disvantags.

This page describes a simple way to determine the main RF characteristics of a Wifi (IEEE802.11b/g wireless LAN) antenna.

A vertical antenna for 40 and 80 meters band with no need of antenna tuner, based on a telescopic fiberglass mast of 48 feet by N8NSN

Experiments with phased wire vertical antennas on 40 meters at VA7ST

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.

Remote Control Antenna Switch made with two circuits board

A vertical half-moxon for the 7 Mhz by F6IRF

A quarter wave vertical end-fed antenna for the 40 meters band. As all vertical antennas, also this aerial requires a good earthing system. In this project the ground is composed by twelve 4, wires buried in the lawn by using a spade to create a slit to drop the wire into.

80 meter vertical experiment by Bob Raynor N4JTE

N6RK computer to FT-1000 interface

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

A 5/8 vertical groundplane antenna for 50 mhz

Article about magnetic loops, construction notes and diagrams

W4TI review the popular Yaesu FT 857 quadriband transceiver

This page shows a homebrew vertical antenna based on the Pac-12 antenna design.

A Mini Moxon antenna for 40 meters band project in a well done PDF document

The diagram below shows the basic arrangement of the 2m Half-Wave version of the antenna. A 6m diagram is available too.

Measurements that show it doesn't make much difference

Automatic Amplifier Selection for the ICOM IC-746, 736 and 706MKII Transceivers.

What is ground?RF ground and the ground plane, how can I tell if I have a good ground? ground loops

A portable VHF home-made Yagi-Uda antenna, that is extremely easy to build and very cheap. Moreover this antenna, while dismounted is just 1 meter long, and the total weight is just 100 grams.

A multiband 20/40/75/160 trap dipole antenna plan by KG0WX