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This is a 70cm big wheel antenna which is used at DB0FAI beacon

This Arduino project decode ICOM CAT frequency information and switch antennas according to preset values. RX and TX antennas can even be different, a project by ON7EQ

The 10-meter EH Antenna document details the construction and performance of a specific EH antenna design for the 10-meter band. It describes the integration of an L+L balanced matching network, a key component for impedance transformation, and highlights the addition of a tuned coaxial trap. This trap, consisting of 8 turns of RG58 coax wound around PVC tube and resonated at 29 MHz with a 10 pF capacitor, effectively inhibits common-mode current on the feeder, stabilizing antenna tuning. The resource presents a circuit diagram in Figure 1 and assembly details in Figure 2, illustrating the use of PVC plumbing tube as host material for dipole cylinders made from recycled aluminum tubing. It also explains the fabrication of capacitor stators and slider sections from thin aluminum tubing. The author, Lloyd Butler VK5BR, discusses initial challenges with feeder interaction and how the tuned trap resolved these issues, leading to stable tuning. Limited backyard tests indicate that the antenna, with the trap fitted close to the input connector, might exhibit similar field strength for both low and high angle transmission, suggesting a potential skewing of the signal. The document references previous articles by VK5BR in "Amateur Radio" for further operational details of the matching network and trap functionality.

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

RTTY, Amtor, packtor, SSTV reference by WM2U

This article reviews the proposition that a 4:1 current balun in the style of Guanella can be constructed with both pairs of windings sharing a common magnetic circuit.

Great shareware software collection for ham radio, includes prefix finders, locators,frequency generators and links to other ham radio software.

Easy to use Audio Spectrum and PSK31 decoding program specially designed for SWL's who don't need TX or for anyone who just like to monitor PSK31 or analyse signals. Adjustable DSP and Spectrum settings for audio and frequency spectrum to set for best decoding of PSK31.

An article on TX and RX antennae for the low bands 80 and 160m by EI7BA

Collection of article and posts on beverage antennas

MultiKeyer is a dedicated computer keying program designed for amateur radio operators engaging in specialized operating activities such as Earth-Moon-Earth (EME) and Meteor Scatter, as well as general contest operations. It provides distinct modes for both CW and Phone transmissions, enabling automated message sequencing and playback of pre-recorded audio files. The software's interface shares a similar "look and feel" to the popular WSJT Meteor Scatter/EME program, facilitating ease of use for operators familiar with that platform. For CW operations, MultiKeyer offers an EME Auto mode for sending timed messages crucial for EME and Meteor Scatter, alongside a Contest mode that handles automatic CQ calls and preprogrammed messages. On the Phone side, it features a Sequenced Phone mode for transmitting prerecorded .wav files during Meteor Scatter events and an Auto Phone mode for contest use. The program leverages serial COM ports for CW and PTT signaling, and the soundcard for .wav file playback, with configurable PTT interrupt options. MultiKeyer integrates with TRX-Manager for PTT and CW keying, and can send callsigns for logging. It also supports WSJT-style "callsign.txt" files for lookups and adheres to the SO2R protocol for parallel port connections. Designed for Windows 98 and NT, it generally functions on Windows 95, ME, XP, and 2000, requiring a 133 MHz Pentium-class processor.

How to build a multi-band dipole antenna with a single coax feed. Instructions for a 160M antenna that will fit in the space that a 75M dipole will with almost as good of results as a full size 160M dipole.

Experiments by G8JNJ on wire antennas for low bands. Based on these tests, conclude that for multiband (160 to 6m) operation, in a restricted area it is very difficult to beat a G5RV, especially the ZS6BK version.

You've heard MS pings, of course. But what does a HSCW ping sound like?

If you have a computer with word processing software and a printer, you can make your own custom QSL cards, with each card individually printed for the ham you just contacted. WA7S show you how.

W3TS small but effective antenna tuner

VE7CA experiments on 160 meters band antennas, looking for better performances on reception.

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.

VU2RAR basic VHF power amplifier suitable for 144-146 Mhz output power can vary from 3 to 25 Watts.

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.

Homebrew 20m CW transceiver by MINOWA, Makoto 7N3WVM

A portable hf vertical antenna setup on a magnetic mount by I1UWF

N7KSB used this 1/2 watt CW transmitter, with a roof-mounted ground-plane antenna to work all continents and over 30 countries

SDR Receiver a compact high performance HF software defined radio receiver designed to be used in fixed or portable stations. Version 2 of the receiver is now available. It now has an RF pre-amplifier using a power MOSFET and other revisions to improve it's performance both as a stand alone receiver and as an IF panadaptor with HF and VHF transceivers.

Streaming Live from Kennett MO

RadioQTH's Vanity Calls service provides a utility for US amateur radio operators to locate available vanity callsigns, specifically focusing on the shortest possible options. The system filters through all potential callsigns within a user's license class and presents only those currently unused, with results weighted by either their actual character length or their equivalent length in _Morse code_. This approach assists hams in securing memorable and efficient callsigns for CW operation. The service also lists recently granted vanity callsigns, sorted by prefix, offering insight into current FCC assignments. It clarifies the common misconception that callsigns are granted on a first-come, first-served basis, explaining the random selection process for applications received on the same day. The platform updates frequently, providing current data on available 1x2, 2x1, 2x2, 1x3, and 2x3 callsign formats, which are highly sought after by _Extra Class_ and _Advanced Class_ licensees.

Easy to use Audio Spectrum- and PSK31 decoding program specially designed for SWL's who don't need TX or for anyone who just like to monitor PSK31 or analyse signals. Adjustable DSP and Spectrum settings for audio and frequency spectrum analasys or to set it for best decoding of PSK31 signals. By ON6MU

Introduction to NVIS advantages and disvantags.

A greyline map that automatically refreshes every five minutes DX.QSL.NET

An antenna system is more easily interfaced to a radio when the input reactance at the feedline terminals is low or close to series resonance

Flexnet and AGW packet engine tested and reviewed by IZ7ATH

Eham users review of Kenwood TS-2000

Launching a balloon or kite supported tall vertical or protracted inverted L.

By 9H1EL, supports RSGB 21-28, BERU, IOTA contests, FOC marathon and IARU 50MHz trophy, Control of FT1000MP, all Kenwood and ICOM Radios which have CAT system.

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

A freeware windows based Morse Code program written in Visual Basic 6 with source code freely available! The program uses DirectX DirectSound for some features. You may download the source code and/or the executable at the bottom of the page.

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

Various radio related software, including some antenna analysis, and impedance calculators.

LOGvrr, a **freeware logging software** developed by IN3VRR, provides amateur radio operators with essential tools for managing their contacts. The resource details various downloadable components, including the core LOGvrr application, an international callbook with approximately 1.8 million callsigns, and utility programs for installation and data conversion. It supports functionalities like logging QSOs, managing awards, and interfacing with PacketCluster systems, with specific instructions for installation on Windows operating systems, including compatibility notes for Windows 10 and 11 using Hyper-V or DOSBOX. The site also offers external tools and documentation, such as the FAQ_VRR.PDF manual which covers installation, printer configuration, ADIF conversion, and Packet setup. It references third-party software like Mercurio and BV QSL Management for QSL printing, and ADIF2QSL for label printing, highlighting LOGvrr's ability to export QSOs in **ADIF format** for integration with services like LoTW. The resource includes historical updates, with the latest core component update in August 2014, and notes on the CallBook's maintenance up to 2015.

Presented here is a high-performance, circularly polarized omni-directional antenna that is easy to build, easy to tune, inexpensive, and will work all the mode J Low Earth Orbit (LEO) satellites

Dedicated ham radio internet gateway and server system. It is intended for use by RF gateways and PC users connected to the internet

Demonstrates the construction of a base-loaded quarter-wave vertical whip antenna, suitable for both mobile and portable HF operations. This design utilizes a vehicle body as a ground plane for mobile use or a counterpoise for field deployment. The article details the selection of materials, such as a _glass fibre tubing_ former and 24 s.w.g enamelled copper wire for the loading coil, with specific turn counts suggested for 20m (around **30 turns**) and 40m (around **50-60 turns**). It outlines a practical tuning method using an SWR bridge and even an audible signal approach, emphasizing careful adjustment of coil turn spacing or whip length to achieve optimal SWR. The resource also mentions the use of an antenna analyzer for more precise tuning, contrasting it with the SWR method.

Based on the N2PK design, this swr meter use a stockton directional coupler

Understanding high-frequency (HF) skywave propagation is crucial for amateur radio operators seeking to optimize long-distance communications. This resource details the fundamental principles of HF radio propagation, including the properties of electromagnetic waves, the characteristics of various HF bands, and distinct propagation modes such as skywave, ground wave, and line-of-sight. It places significant emphasis on the ionosphere's pivotal role in refracting HF waves, explaining how solar activity directly influences ionospheric conditions and, consequently, propagation paths. The resource integrates real-time monitoring capabilities, featuring dynamic charts and data from DX clusters, WSPRnet, and the Reverse Beacon Network, which allow users to track current band activity and propagation conditions globally. It also delves into advanced topics like Near Vertical Incidence Skywave (NVIS) and gray line propagation, providing insights into ionosonde data and various propagation prediction models. The site presents a detailed analysis of solar-terrestrial interactions, geomagnetic indices, and space weather phenomena, illustrating their direct impact on HF communication reliability. Practical tools and applications are highlighted, including real-time QSO planners, online Maximum Usable Frequency (MUF) maps, and alerts for solar flares or geomagnetic storms. The guide systematically breaks down complex concepts into accessible chapters, offering a structured approach to learning about ionospheric regions, diurnal and seasonal effects, and the interpretation of propagation indicators like foF2, MUF, and Lowest Usable Frequency (LUF). This makes it a robust reference for hams aiming to deepen their technical understanding and improve operational effectiveness.

Shareware program to receive and transmit high speed CW (morse code) used in MS (amateur radio communication mode) with MS Windows 95/98 and sound card.

How to make easily your N-type connector, pictures and procedure, step by step

This is a simple calculator for solving the antenna wire catenary between to end points given the design wind speed, mass per unit length of the wire, wire diameter and Gross Breaking Strength of the wire.

Morse Keys by Gordon G4ZPY

Edited by Oz6OM to find out who's on 50MHz expeditions anywhere around the world. Most recent news on the web.

Improved Helical Antenna Design for 802.11b WLAN by PA0HOO