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These charts show the New Zealand bandplan

Performance of an unloaded ground mounted vertical as a multi-band HF antenna.

Presents the VHFDX.EU web cluster, a specialized resource for VHF, UHF, and microwave DX spotting. It details the cluster's functionality, including real-time spot aggregation and a DXCluster Map interface for visualizing activity. The resource highlights its integration with the MMMonVHF backbone, ensuring a robust data flow for monitoring band openings and propagation events across higher frequencies. It also references reviews of the ON4KST and N0UK chat systems, which are frequently used in conjunction with VHF DX operations. The platform offers a mobile-optimized view for on-the-go access to DX spots, catering to portable and mobile operators. It further provides daily ES (Sporadic E) spot summaries, a critical feature for VHF operators tracking this specific propagation mode. The cluster serves as a central point for operators to share and receive information on rare grid squares, contest activity, and general band conditions above 50 MHz.

Vhf and UHF homebrewers of hardware and antennas. Find help, idea, or someone with just the same interest as you.

NOAA HRPT - High Rate Picture Transmission, the main source of high quality data from polar orbiting meteorological satellites

Replacing the Yaesu FT100D SRF7043 VHF/UHF RF MOSFET Power Amplifier

VHF UHF Microwave EME Standings, a Who's Who on top in USA

Have you ever thought of setting up a portable HF station for an activity ?

This converter uses the popular NE602 mixer/oscillator chip and allows reception of signals below 500 kHz on a 3.5 – 4 MHz HF receiver

Introduction to WSPR beacons. Article describe WSPR2 and WSPR15 beaconing mode and include a frequency reference table for both WSPR modes

The page provides detailed instructions on how to build a 60 meter End Fed Half Wave Antenna Tuner, with large pictures and diagrams. It is aimed at amateur radio operators looking to construct their own antennas for the 60 meter band.

How to calculate range for a VHF antenna with a simple formula and how to increase VHF coverage.

Sense The Right Way To Go With The HANDI-Finder

The Rochester VHF Group, the oldest VHF-Oriented club in the World

VHF – Based on realtime APRS reports. This map shows real-time radio propagation from stations operated near 144 MHz. It uses data gathered by Automatic Packet Reporting System-Internet Service (APRS-IS) from packet stations in the amateur radio service. The map shows activity from the past hour. Paths are smoothed to create a color-coded footprint indicating the distance VHF signals are likely to be traveling.

This article serves as a beginner-friendly guide to constructing a simple VHF dipole antenna for 2 meters, perfect for novices in the hobby. With an emphasis on affordability and simplicity, it explains the basics without overwhelming technical details. Recommendations for coaxial cable and mounting methods are provided, offering practical solutions for effective communication. By following these instructions, novices can build a functional antenna without breaking the bank.

The TransWorld Antennas TW4040 The Adventurer Monobander™ is a portable HF antenna designed for rapid deployment in field operations, including **SOTA** and **POTA** activations. This manual details the antenna's assembly, tuning procedures, and operational guidelines for optimal performance on the 40-meter band. It outlines the specific components, such as the telescoping whip and base unit, required for proper setup. Instructions cover mast erection, radial wire deployment, and impedance matching to achieve a low **VSWR** across the designated frequency segment. The document also provides guidance on antenna orientation and environmental considerations for portable use. It specifies the antenna's power handling capabilities and physical dimensions when fully deployed and collapsed for transport.

VHF/UHF Contest Logger is a windows freeware contest log program that supports ARRL VHF/UHF contests and other popular VHF contests

A 600W 1.8 MHz to 54 MHz power linear amplifier made using rugged MRF300 transistors featuring output power between 580W and 750W depending on band, power supply: 48V, 18A typical, 20A max

A portable VHF/UHF portable 6 element Yagi antenna project by OH2GVB

This map shows real-time radio propagation from stations operating on 11 bands between 1.8 and 54 MHz in the amateur radio service. The display shows world-wide activity from the last 15 minutes and is automatically updated about every minute. Data for the map is gathered from several online sources: WSPRnet, Reverse Beacon Network (CW, FT4, FT8), PskReporter, and DX Cluster.

Operating on the 146.880 MHz repeater, the Inland Empire VHF Radio Amateurs (IEVHFRA) hosts a weekly net, providing a consistent on-air gathering for amateurs within Eastern Washington and Spokane County. My experience with similar regional VHF nets confirms their value in fostering local ham radio community and sharing information, often covering topics from equipment troubleshooting to upcoming hamfests. The club, active for over **50 years**, also organizes the _Inland Empire VHF Tailgate Swap_, an event featuring vendors, emergency communication demonstrations by Spokane ARES-ACS, and POTA/SOTA activity setups. Such events are crucial for hands-on learning and direct interaction, which I've found invaluable for new licensees and seasoned operators alike. Beyond on-air activities and events, IEVHFRA supports the hobby through amateur radio classes and testing, facilitating new license acquisition and upgrades. They also maintain an online messaging group for members, ensuring continuous communication and information exchange.

How do we make an HF station work more effectively? Antennas are the key!

Complete instructions on tuning the Butternut HF2V on four bands, 80, 40 , 30 and 15 meters

The Superantennas MP-1 portable HF antenna is analyzed for its design and field performance, particularly its high-Q loading coil and 3/8-inch mounting. The review details the antenna's construction, including an 8-inch vertical section, a large-diameter loading coil tuned by a sleeve, and a 4-foot whip that disassembles into six rods for transport. Initial testing with the supplied 10-foot ribbon cable "ground plane" yielded poor SWR and RF hot conditions, indicating an inadequate ground system. Further experimentation with longer radials and resonant counterpoises for each band improved matching and eliminated RF hot issues, but introduced significant operational complexity. The author notes the difficulty in optimizing both counterpoise length and coil setting without an antenna analyzer, and the sensitivity of the MP-1 to counterpoise deployment. The review also discusses the recommendation to tune for maximum received signals rather than minimum SWR, often necessitating an external ATU due to the antenna's typical low impedance. The **MP-1**'s critical dependence on resonant counterpoises for effective operation, especially when elevated, is highlighted as a major drawback for portable use. The author ultimately sold the antenna, concluding that despite its sound technical design, its fussy nature and the need for extensive counterpoise management or an ATU detract from its portability and convenience compared to simpler, less expensive dipole solutions. The **Superantennas MP-1** is deemed a flawed portable antenna, requiring considerable effort to achieve its claimed performance.

A 70 MHz QRP transverter project

GUI for the KK7KA Wolf software, that was originally written as command line interface only. Wolf is a weak signal software

Influence of the ionosphere on the EME signals by EAVQ

BeaconSpot.uk provides an accurate, real-time picture of microwave and VHF/UHF beacons operating across Europe, alongside a worldwide listing of 6-meter beacons. The platform allows users to retrieve detailed data for individual beacons, facilitating in-depth analysis of signal characteristics and propagation paths. Interactive maps visualize beacon distribution by frequency band and display spot coverage for each station, offering a clear geographical overview of active beacons. The system integrates real-time DXCluster spots, sourced from contributors like Alain, ON4KST, and Pascal, F5LEN, and enables users to submit outgoing spots directly to the DXCluster. Beacon keepers can manage their beacon data, receive email alerts upon being spotted, and track their station's ODX (Outstanding DX) records. For every received spot, the distance to the beacon is automatically calculated and displayed, aiding propagation studies.

Zeus Radio program is designed specifically for the ZS-1 transceiver and supports all the basic functions (RIT, XIT, SPLIT, Noise Reduction, Auto Notch Filter, etc.) in order to work in the broadcast brought only pleasure. Zeus Radio works also with Hermes, Anan, Afedri, Red Pitaya, HiQSDR, Odyssey, Extio, RTL-SDR, Peaberry, Winradio, SDR-IQ, Afedri

VHF Broadcast Passband Filter (88 108 MHz) by DF9CY

A interesting guide to help get started with HF published at Essex Ham

Homebrewing portable antennas for field day operations

Building the UHF Cheap Yagi for Satellite Communication

This article is about a 4 element yagi VHF antenna designed to be easy to be assembled and suited for portable operations

I0GEJ page on the Elecraft K3 transceiver

The MMMonVHF database, curated by DL8EBW, currently lists 63,455 entries for VHF operators, providing a searchable resource for locating stations active on 144 MHz and higher bands. Operators can register their callsigns to be included, with specific criteria such as participation in _MS_ (Meteor Scatter), _WSJT_ modes, or _EME_ (Earth-Moon-Earth) operations required for inclusion in the `call3.txt` file. This resource facilitates VHF DX expeditions and contest planning by allowing users to identify potential contacts within a geographical area. The database supports various VHF/UHF operating modes, including those focused on weak signal propagation. Statistical data regarding the database entries is also presented, offering insights into the distribution of registered VHF activity.

FTDX 5000 product page with related accessories

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

Ukrainian radioamateur on HF: DX News, Contesting, Propagation, Conference, Photo, Radioamateur Map, Online Logs etc.

What Are Pirate Radio Stations and Why Listen to Pirate Radio Stations, How to Listen To Pirate Radio Stations

Mailing list on running or monitoring HF beacons

Multi language contest log program for 9A VHF UHF contest. Freeware for Windows

Receiver performance review of the Kenwood TS-890S HF,50MHz,70MHz amateur radio transceiver by Sherwood Engineering

Having Fun & Fellowship since 1955. The Keystone VHF Club has extensive facilities right outside Rocky Ridge Park just northeast of York, PA.

This home made antenna provides around 10.5dBd gain on 70cm, and 6.5dBd gain on 2m, which is more than adequate to work the FM satellites with a handheld dual band radio

The electchester vhf club is located in flushing, queens, ny and operates an arrl coordinated, 2 meter, vhf repeater designed for amateur (ham) radio use.

The intent of this article is to help the semi-non-technical person understand what is inside the Drake TR-7(A) Transceiver, how it works, and discusses simple adjustment and modifications the end-user can perform

2009 IARU HF World Championship Contest Rules

Documents the construction of a **VHF/UHF** antenna addition for the Buddipole HF antenna system, leveraging the existing Versa-Tee component. The project details the fabrication of a custom antenna mount from angle aluminum, including specific drilling and tapping for 3/16"-24 bolts, and the creation of radials from Simpson Strong Tie Insulation Supports. It specifies radial lengths for 70 centimeters (6 inches from the center stud) and 2 meters (19 1/4 inches), noting the use of wire nuts for safety. The resource outlines the construction of a mast from 1/2" ID PVC conduit, connected with 3/8"-24 connecting nuts and bolts, mirroring the Buddipole's modular design. It describes the integration of a mobile dual-band antenna with a 3/8"-24 mounting stud and the custom coax setup with BNC and **PL-259** connectors. Field testing with an FT-817ND and a separate dual-band SWR meter confirmed good SWR on both 2 meters and the 440-450 MHz section of 70 centimeters, with positive reception reports during Field Day activities. Further, the article describes the creation of a custom carrying solution, including a 22-inch tripod bag and a fabric roll-up, to emulate the portability of the original Buddipole system.