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The Answer To Suburban DXing On the Low Bands - by Merv Schweigert, K9FD

If you find external wire antennas obtrusive for amateur radio or short wave listening, then this is the antenna for you, is just 1 meter diameter

WorldRadio Article on Petlowany antennas base on this principle: if a length of wire is wound into a spiral-shaped coil and excited by a radio frequency current connected to the innermost portion of the coil, it will then, and only then, exhibit RF characteristics that closely approximate those of a resonant linear wire of the same length

Traps can be one way round multiband coverage without the need of an atu. Learn how to homebrew your own traps

Antenna data, and design note for this horizontal loop antenna resonating on 80 Meters by K0ZE

A project for a 144 Mhz halo antenna

Log Online for XT2TT in real time

Operating amateur radio satellites effectively requires precise knowledge of their orbital mechanics and pass times. Gpredict, a real-time satellite tracking and orbit prediction application, addresses this need by allowing operators to monitor numerous satellites simultaneously. It displays critical data such as position and pass details through various visualizations, including lists, tables, maps, and _polar plots_. Unlike many other satellite tracking programs, Gpredict introduces the concept of visualization modules. These modules enable users to group satellites and configure each group independently, offering unparalleled flexibility in how orbital data is presented. This modular approach supports tracking satellites from multiple observer locations concurrently, which is particularly useful for stations with diverse antenna setups or remote operations. Originally a GUI client for John Magliacane's _Predict_ program, Gpredict evolved to integrate its own tracking code for improved performance. The software is distributed under the GNU General Public License, ensuring it remains free and modifiable for the amateur radio community.

Demographics of amateur radio operators

There are many kinds of satellite antennas that will get you on the birds and allow you to have lots of fun

Yaesu FT-857 offers an availability of changing parameters through the hidden menu.

Rolling your own transformers and chokes. Rewinding salvaged power transformers, considerations and step-by-step guide

A suitable high gain 70cms antenna for SOTA operation was sought that did not have the drawbacks of a long Yagi antenna, principally a narrow beamwidth and bandwidth.

Bill Orr W6SAI ham radio techniques. Improving ground connection, computer analysis of the antenna, modelling sample antennas pdf file

The dynamics of antenna design

The FL-2100Z amplifier referenced in the following images is the 6-Band model covering 10m thru 160m (no WARC bands) and not the 9-Band version that included the WARC bands. Modifications, schematics and manual

This project is intended to aid in tuning a balanced antenna or feedline that has a high impedance 100-600 ohms

Project of a windom multiband antenna for 10 to 80 meters in portuguese

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

Mods for ICOM IC-706

A 7 elements yagi beam monoband antenna for 14 Mhz by VE3GK

The interface described here has been verified to work on the TH-G71 and also the the TH-F6A/TH-F7E

Amateur Radio software for transmission/reception of JT65 protocol. Brought to you by hb9hqx

Freeware remote control software for Kenwood TS-870 by EC4DFP

A 144 MHz dipole antenna made from coax, PVC pipe, and aluminum foil tape

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

Constructing a Lindenblad antenna for 137MHz NOAA satellite reception involves specific design considerations for optimal performance. The resource details the use of 4mm galvanised steel fencing wire, 300-ohm television ribbon cable, and wood/plastic components for the antenna structure. Key dimensions for a 137.58MHz-resonant antenna are provided, derived from the ARRL Satellite Handbook, specifying s, l, w, and d as 42, 926, 893, and 654mm respectively. The antenna is designed for Right Hand Circularly Polarised (RHCP) signals, requiring the four folded dipole elements to be tilted clockwise by 30 degrees. A significant aspect covered is impedance matching between the antenna's 75-ohm impedance and a typical 50-ohm receiver input. A twelfth-wave matching transformer, constructed from 117mm sections of 50-ohm RG-58 and 75-ohm RG-59 coax with a 0.66 velocity factor, is described. The article also addresses coaxial cable and connector selection, recommending 75-ohm Type-N connectors for RG-6 cable in professional setups and F56/F59 connectors for general use, while strongly advising against PL-259/SO-259 connectors for VHF. Strategies for mitigating Radio Frequency Interference (RFI) are discussed, including antenna placement to shield from local TV transmitters and the use of commercial or DIY band-pass filters, such as cavity resonators or helical notch filters, along with ferrite chokes on coaxial cables. Antenna orientation is explored, noting the Lindenblad's 'cone of silence' directly overhead and its maximized sensitivity towards the horizon. An experimental vertical tilt of 90 degrees is presented as a method to improve overhead reception and reduce interference from strong horizontal signals, particularly relevant in high RFI environments like the Siding Spring Observatory site.

ERP Calculator is an Amateur Radio software utility designed to perform a side-by-side comparison of two Ham Radio antenna systems. ERP Calculator comes pre-programmed with data files including published data for several popular brands and types of coax cable as well as several popular antenna system brands and models. ERP Calculator displays values of ERP, Antenna Power Gain, Antenna Feed point Power, Antenna System Gain in dB, Antenna Gain in dBd, SWR Attenuation in dB, SWR Power Attenuation, Coax Loss in dB, and Coax Power Loss

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

Remote Control Antenna Switch made with two circuits board

Antenna covers all bands 80-10 meters + 30, 17, 12 meter WARC bands, need a lot that is at least 100 feet across.

Quick reference table on understanding A K SFI indexes and how can be translated in usable frequency opportunities

Xcorder is a windows Freeware audio recorder written by MM0BFF, designed to work mainly with radio receivers but may be used also in several different ways for audio recording needs.

W4TI review the popular Yaesu FT 857 quadriband transceiver

The TU2T DXpedition log provides a critical resource for verifying contacts made during the 2011 operation from _Ivory Coast_. This online tool allows operators to quickly confirm their QSOs, which is essential for QSLing and award applications. Users can typically search by callsign, date, or band to locate specific entries, ensuring accuracy for their personal logbooks. Such online logs are indispensable for DXers pursuing awards like **DXCC**, as they offer immediate confirmation of rare or distant contacts. The ability to verify a QSO without waiting for a physical QSL card significantly streamlines the award application process. This particular log facilitates the confirmation of contacts with the TU2T operation, a highly sought-after entity.

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

Collection of modifications notes for the Kenwood TS850

Why 6 meter hams design the best antennas

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

The MFJ-940 VERSA TUNER II is a useful little antenna tuner for the HF-bands. However it suffers from a minor design error, which can be easily rectified.

Outlines recommended operating procedures for amateur radio repeaters, detailing best practices for general on-air conduct. It emphasizes using simplex when possible, monitoring the frequency before transmitting, and maintaining concise, thoughtful transmissions to avoid monopolizing the repeater. The resource also stresses the importance of legal identification, such as the Canadian requirement at the beginning and end of a contact and every thirty minutes of operation. Furthermore, the article provides specific instructions for **autopatch** operation, including access codes and the necessity of brief calls, while cautioning against misuse for long-distance calls or commercial purposes. It highlights the financial support expected from regular users to maintain repeater infrastructure. Finally, the guide differentiates between permanently linked repeaters, which offer extended coverage, and **code access linked repeaters**, explaining the sequence of identification and code entry required to establish and terminate links for broader communication.

D3+ High Performance Antennas for Field Day. This article describes versatile broadband wire antennas. These antennas will double your effective radiated power over a dipole, will be easy and inexpensive to build and install, and will be simple to match.

Stream your radio audio output with free version on unreal media server. Support live audio and video broadcasting via internet

About numbers stations, and their criptic transmissions, where to listen to them and some audio recording samples by fascinating shortwaves

KB1GW's collection of beverage antenna information

Simple, inexpensive and lots of fun! Here is an easy to make home brew antenna that can get you on the air working satellites or be built for use as a portable hand held antenna to extend the range of your HT.

The Grid Yagi (or Grid Quad) is a high performance yagi antenna that can be built with readily obtainable inexpensive materials. Described here is a 6 element 2 meter version with a boom length of about 1 wavelength, shown

Feeding a G5RV Overview by VK1OD

A project for a multiband HF windom antenna by VE2CV and VE3KLO

Map of italy with amateur radio prefixes and grid squares