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VP8PJ by The Perseverance DX Group will activate the South Orkney Islands IOTA AN-008 from approximately Feb. 21, 2020 through March 5, 2020

WSJT DX Aggregator is a program that allows the stations using the WSJT-X or JTDX or MSHV programs to automatically upload DX reports to DXMAPS.com

A polarity checker is a very useful item to have around the shack and in a go-kit. This project, inspired by a QST article on powerpole connector protection illustrate how to build a polarity checker.

Presents a detailed construction guide for a 9 dB, 70cm collinear antenna, utilizing readily available _RG58/U_ coaxial cable and PVC pipe for housing. The resource outlines the critical calculations for ½ wavelength sections at 444 MHz, incorporating the coaxial cable's velocity factor of 0.66, which yields a section length of 223 millimeters. It specifies the preparation and soldering of eight such half-wavelength sections, each cut to 231mm to allow for trimming, forming the core of the array. Further instructions detail the integration of a ¼ wave element (169mm #16 solid wire) at the top and a ¼ wave aluminum tube (160mm, 5/16 inch) at the bottom, crimped to the feed point's braid. The guide also addresses RF common mode current suppression by suggesting the use of _FT50-43_ toroids on the feedline. Final assembly steps cover mounting the antenna within ¾" PVC pipe using a wooden dowel, waterproofing connections, and initial SWR checks. The article also discusses scaling the design for different element counts and other VHF/UHF bands.

The Steampunk-styled air cannon sending tennis balls flying at 500 mph!

Constructed in May 2008, this innovative 4m tall electrically full-size halfwave vertical dipole, tunable to multiple bands, offers HF coverage despite its space-saving design. Inspired by cost-effective DIY alternatives, the antenna design departs from conventional center-fed approaches, utilizing asymmetrical dimensions. Despite resonance challenges, the antenna's performance remains viable, boasting broad bandwidth and adaptability, as demonstrated through SWR measurements and EZNEC predictions.

A homemade MFSK16 APRS HF tracker, worked pretty well for 1.5W on a Lipo supply with only 2 of the 3 BS170 FETs in the final

Logisim is an educational tool for designing and simulating digital logic circuits. With its simple toolbar interface and simulation of circuits as you build them, it is simple enough to facilitate learning the most basic concepts related to logic circuits.

DX Cluster spots represented in a google map, for 10m 6m 2m bands taken from the VE7CC DX Cluster. Some filtering options are available.

An Excel sheet calculator for the T2FD wire antenna. The sheet has been proved to work either on LibreOffice and Apple Numbers. Just input the resonating frequency to get the proper size and dimensions.

DMR Handheld TDMA Tier I and Tier II VHF or UHF product review with information on accessories

A medium power End Fed Half Wave Antenna coupler, specifically tuned to the QRP frequency of 7030 kHz. Constructed from coil stock and capacitors, it achieves an impedance ratio of 64:1. The coupler has proven effective for power ranges from 2 to 100 Watts on the 40m band.

Programming software for the Icom IC-R2 handheld receiver and scanner.

How to solve the problems with the ICOM IC R7100 receiver that every time the squelch opens or closes, it produces a clicking noise.

Kantronics Pinouts with information on Icom, Kenwood Motorola, Yaesu and Vertex radio connections.

Dipole for 40m band. It is a simple linear loaded dipole feeded with 450-Ohm openwire feedline. Designed it for resonance at 7.050 MHz, can be tuned on 30m and 80m bands with an external antenna tuner. Build with simple electrical copper wire (2.5 mmq/13 awg) and two fishing poles with size of about 7 m/23 ft.

Ham racio clip art collection with free to use images. Additional amateur radio clip art can be found by changing the search term

The antenna is built on a cross-shaped frame with spar width (and height) of 48 inches, providing a height of 52 inches and a width of 49 inches. This antenna costs only about $45 to construct and can be built in just a few hours using simple hand tools. The best part is that the performance on 160M and 80M is excellent

This antenna works on 17, 20, and 30 meters, with the best bandwidth on 20 meters. The bandwidth on 17 and 30 is quite small but usable. There is a 20 KHz bandwidth on 20 meters.

This document details the construction of a multi-band end-fed antenna, suitable for situations with limited space for larger antennas. The design utilizes a 1:49 to 1:60 impedance transformer to match a half-wave wire antenna fed at one end. Compared to a traditional dipole, this antenna resembles a highly unbalanced Windom antenna with one very long leg and a virtual short leg. The design eliminates the need for radials but relies on the coax cable shield for grounding. The document recommends using at least 10 meters of coax and installing a common mode filter at the entry point to the shack for improved performance.

This article presents the C-Pole antenna project, a compact, ground-independent vertical antenna designed for amateur radio operators. It features a folded half-wave dipole configuration that eliminates the need for radials, making it suitable for various locations, especially in deed-restricted areas. The C-Pole offers efficient performance with a 2:1 SWR bandwidth of approximately 3%, and it can be easily constructed using common materials. Additionally, the article discusses practical aspects such as feed-point impedance transformation and balun design to optimize functionality and minimize losses.

This utility program shows the impedance and reflection coefficient parameters (SWR, reflection coefficient magnitude Rho, or Return Loss RL in dB) at both ends of a transmission line and the details of power loss in the line. It includes built-in specifications for approximately 100 different line types. You can modify the specs to see how small changes affect the results or to specify custom lines. All program inputs may be changed directly or you can use spin buttons to make the changes.

A page dedicated tho the IC-756PROIII transceiver. This radio, discontinued, incorporates many of the features that made its predecessors so successful. However, the integration of the latest technology employed in the IC-7800 such as receiver technology, +30dBm class IP3, miniscope makes this new rig the very pinnacle of the IC-756PRO series.

Otto enhances WSJT-X, the popular weak-signal digital modes program for amateur radio. It automates tasks like managing QSOs, prioritizing DX stations, replying to specific calls, and optimizing band usage. Otto works with a modified WSJT-X version (v2.7.0) to add advanced features such as directed CQs, automatic logging, and multi-stream replies. Its intuitive modes streamline operations, while safety measures ensure controlled transmissions. Ideal for DX enthusiasts, Otto improves efficiency and focus, making weak-signal operations more engaging and productive.

Official PDF guide to WSJT-X FT8 SuperFox operating mode published on June 2024 by Joe Taylor, K1JT

Learn how to build a simple tuned loop antenna for the AM broadcast band to improve the performance of your radio receiver. Discover how to construct a loop antenna with readily available materials, such as balsa and basswood, without the need for specialized woodworking tools. Follow step-by-step instructions to create a portable loop antenna that offers good gain and directivity, ideal for pulling in weak stations. Enhance your Ultralight DX'ing experience and explore the world of FSL antennas through this practical DIY project.

2m 70cm 23cm Low noise Amplifiers, 3 Low noise amplifiers Outdoor unit with DB6NT parts completed.

Fans of NIST signals cite benefits including understanding the near-Earth environment

A Trapped dipole inverted V antenna for lower HF Bands. Construction details are for temporary installation. Permanent installations will require additional ruggedising and waterproofing however the basic electronics concepts remain the same. This project includes SWR plots for the three bands and pictures details of the homemade traps.

A Different way to construct a tried and true antenna out of PVC, especially for the 10 meter and higher frequencies.

Common-mode chokes are useful solutions for RFI reduction. Winding a few turns of coaxial cable on the FT 240-31 toroid can reduced the noise below the received noise floor. In this article author measure different chokes

A 20 cm mobile antenna design is presented, addressing the need for compact, mechanically stable solutions for VHF/UHF mobile communications. This resource details the _SN 1/8_ antenna, an alternative to traditional quarter-wave or 5/8-wave whips, specifically engineered for robust performance in dynamic, moving environments. The design emphasizes a spherical radiation pattern, which is claimed to enhance signal reflections and contribute to a 2 dB gain over standard mobile antennas, making it suitable for vehicle installations where discretion and vibration resistance are critical. The construction guide includes diagrams and practical considerations for building this antenna, which is noted for its ease of installation and resilience. The design's compact form factor and inherent stability are key advantages for mobile operators seeking reliable and efficient communication without the bulk or fragility of longer antenna systems. The resource, authored by _F5SN_, provides a practical approach to improving mobile station effectiveness.

An FLdigi computer interface from spare parts made with a mic modification

A review of the most popular and traditional methods to learn morse conde and a different method that foreseen to learn 100 most common words in CW

Magnetic loop receive antennas manufacturer. W6LVP loops cover 2200 through 10 meters (135 kHz through 30 MHz) with no tuning or adjustment.

An technical page on coaxial cables that describes what coax cables are, how do coax cables works, what are RG cables and difference with several coax cable types, what they are used for, connector types and cable sizes

This article is an attempt to shed some light on this misunderstood component, covering topics like why you need a common mode coke, what it does, what properties it should have, ho to build one and how to measure its performance.

The Saturn PCB Toolkit is the best freeware resource for PCB-related calculations you can find. It incorporates many features that PCB designers and engineers are in regular need of like current capacity of a PCB trace, via current, differential pairs and much more. Please download our PCB Toolkit today for free and enjoy!

World Time Zone is an online quick reference chart that displays the world time zones in detail. DST is also indicated by yellow markers on the map. UTC difference is marked with different colors, and if you point and click will show up area details

The York Radio Club has been serving the Interests of Amatuer Radio for over 78 Years, since its inception in 1936

144MHz 2m Portable Yagi VHF Beam Antenna. This page contains construction details on a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

The Beverage we use is a DX Engineering RPS-1 dual directional 360 foot 109,7 m, oriented due North/South, six feet 1,8 m off the ground. The antenna uses 450 ohm ladder line as the antenna, and 75 ohm RG-6u for the feedline. The antenna runs atop the fence between our property and 5 acres of pasture next door.

The CWJF Group began in the 80's with the ideas of an excellent telegrafist, our dear friend Julio (PY4AG) who with customary cordiality taught those interested in practice of morse code.

Showing aircraft scatter reception in action.

Icom IC-R9500 Professional Receiver with 5 roofing filters, 48 kHz DSP

VP9KF Log Online Search Page

Harald with be QRV from Kigali, Rwanda from 5th to 24th June 2018 He will be running CW, SSB, RTTY and the new FT8 Mode

RF Power measurement using a DVM, RF Power measurement using an RF detector, RF Power measurement using an Oscilloscope and using a Spectrum Analyzer

Integrating a **160-meter vertical wire antenna** with an existing 80-meter Yagi system presents unique challenges for Top Band operation. This project outlines the author's experiences with seasonal antenna removal and reinstallation, a necessary task for agricultural land use. It details specific issues encountered, such as incorrect coil sizing and relay configuration problems, providing practical insights into common pitfalls. The article describes the iterative tuning process, comparing **NEC model** predictions with actual on-air performance. It emphasizes the importance of precise measurements and adjustments to achieve optimal resonance and impedance matching. The author shares lessons learned from troubleshooting, including the impact of ground system integrity and feedline considerations. Concluding with an antenna checkup, the resource addresses long-term maintenance aspects, including galvanic corrosion prevention and general upkeep for reliable operation.

Mad your own simple FS meter. It is the simplest thing to make and is good enough to see if the antenna under test is radiating more power than your old ground plane, old mobile vertical or just radiating at all in a particular direction or in all directions.