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Visualizes real-time amateur radio propagation spots using data from the PSK Reporter MQTT stream, providing immediate situational awareness for radio operators. The platform displays spots from various modes, including CW, WSPR, and JT65, in addition to the dominant FT8 digital protocol. FT8 Live focuses exclusively on live data streams, prioritizing current signal activity over historical archiving, which differentiates it from the official PSK Reporter map. A key feature is its integration with the Summits on the Air (SOTA) API, facilitating SOTA chasing by cross-referencing transmitting callsigns with SOTA alerts; a station is identified as an activator if the spot correlates with a scheduled alert within an eight-hour window. The user interface was developed by Arron (ZL1AN), with core data from Philip Gladstone (N1DQ), and stream delivery managed by Tom Stanton (M0LTE).

2020 Jan 6 - 2020 Feb 29 By DJ4KW as V31YN and DK9GG as V31GW; 160-10m; CW FT8 SSB; see Web for full QSL and operational details QSL via LoTW.

Learn about the practical design and construction of Yagi antennas for ham radio operators. This post explores the benefits of Yagi antennas in receiving and transmitting RF signals, concentrating signal energy in one direction for long-distance communication. Discover the theory behind Yagi antennae, the importance of element size and spacing, and the resources available for sizing and construction. Whether you're interested in OTA television or amateur radio communication, understanding Yagi antenna design can enhance your signal reception and transmission capabilities.

The weather station described here uses a TTGO v3 1.6.2 module and various sensors. It displays the data on an OLED screen and transmits them among a choice of protocols to the APRS, APRS-IS, Wunderground servers or via an MQTT broker. APRS data is transmitted on 433.775 MHz (can be changed) using the LoRa protocol. APRS beacons picked up by iGate gateways are then transmitted to APRS servers.

MLog 0.8d is a freeware logging software designed for Windows operating systems (NT, 98, ME, 2000, XP) that facilitates the logging, management, and analysis of amateur radio QSOs. It features a customizable input mask for rapid contest logging, a robust search function for existing contacts, and immediate data storage in CSV format to prevent data loss. The software also includes a double-check mechanism against reference logs during callsign entry, integrated DXCC information, and a "magic field" for streamlined data input, all within a single-window interface. Key functionalities include graphical QSL card management via _QSL-Collection_, CW output through soundcard or PC speaker, and direct access to _Radio Amateur Callbook_ data. MLog supports transceiver control via _Ham Radio Deluxe_ URLs, offers a detailed world map with locator conversions, and can launch _VOACAP_ through _HamCap_. It provides extensive data analysis options for QSLs, _Locator_ large fields, _DOKs_, _DXCCs_, QSO counts, and user-defined contest evaluations, alongside flexible import/export capabilities for various log formats.

About LoRa, wireless communication technology designed to transmit data over long distances. LoRa provides a means for wireless data transmission over long distances with low power consumption. Practical applications of LoRa in amateur radio

This document details the construction, programming, and operation of a modular WSPR transmitter. The transmitter utilizes an ESP8266 NodeMCU, an SI5351 synthesizer with a TCXO for stability, and selectable low pass filters. Construction involves soldering headers, components, and assembling filter module. The ESP8266 is programmed via the Arduino IDE, requiring library installations and code modifications, including network credentials, callsign, and frequency . The transmitter is powered by USB or Vin terminals and its frequency is selected by jumpers and software settings. The document also covers FCC restrictions and how to use the WSPR network

The article highlights the common absence of modern USB-C ports on handheld ham radios and the limited use of USB for power. The author, [jephthai], shares a solution involving a USB-C cable with power negotiation capabilities, allowing the radio to be powered by USB. By splicing Anderson power pole connectors onto the cable, the radio can now be conveniently powered by a USB battery bank, providing a practical alternative to traditional 12 V batteries for off-grid operations.

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.

1-watt 17-meter cw transmitter that was originally done about 10 years ago as a club project for RAMS, the Radio Amateur Megacycle Society. It uses a VXO, rather novel at the time. It also uses a bandpass filter at the output rather than the usual lowpass

Cavity is often required at a busy site to not only prevent its receiver from being overloaded by off-frequency signals, but also be a good neighbour and prevent low-level signals from your transmitter from getting into other users receivers - not to mention the preventing of those other signal from getting back into your transmitter to generate spurious signals in its own right.

Worldwide Map of shortwave transmitters. Based on shortwave schedule database, this website let you serarch using filters for broadcasts schedule and at the same time to diplay the transmitter map.

Steve Nichols, G0KYA, presents a practical examination of ground systems for vertical antennas, drawing heavily on the empirical research of Rudy Severns, N6LF. He explains that a robust radial field is crucial for ground-dependent verticals, effectively replacing the antenna's "missing half" and mitigating severe RF absorption in lossy soil. Nichols clarifies that surface radials do not strictly require a quarter-wavelength; instead, deploying a minimum of 16 to 32 shorter wires often yields superior results compared to fewer, longer ones. The presentation also addresses the common SWR paradox: a poor ground might show a perfect 1:1 match, but adding radials, while potentially raising the SWR to around 1.4:1, significantly improves true radiation efficiency. Nichols defines counterpoises as elevated wire networks that substitute for earth connections, offering solutions for limited-space installations, such as the **Folded Counterpoise (FCP)** for 160 meters. This resource provides actionable engineering data for optimizing vertical antenna performance.

Vertical antenna tests at the Sonten-Rancabali tea resort in Ciwidey, West Java. The assembly, led by Mr. Dian Kurniawan and the team, took just 20 minutes. Mrs. Mita performed the transmit check-in test, which was received across various regions in Indonesia, including Sulawesi, East Java, and Bangka Belitung. The team will release a video of the test soon and has thanked colleagues YB3HRY and YB0BAW for their reports.

On this page, you will find one of my designs; An Audio Selection Panel (ASP). The Audio Selection Panel allows you to control 4 Transceivers and hear the audio through the built-in loudspeaker and on an external boomset (combination Microphone/ headset). On or more transceivers can be selected at a time to transmit and/ or receiv

Presents two distinct hardware modifications for the Icom IC-7300 transceiver, detailing the necessary steps for each. The first modification, a _MARS_ transmit expansion, involves the physical removal of specific surface-mount diodes (D422) from the main board, enabling transmit capabilities across a broader frequency range, including out-of-band frequencies. It specifies the diode location on US versions of the IC-7300 and suggests using small diagonal cutters if a soldering iron is not preferred or available. The second modification focuses on the internal antenna tuner, aiming to provide wider impedance matching capabilities. This involves adding a **100k ohm** resistor to a designated point within the tuner circuit. The resource also briefly mentions a microphone modification for the _HM219_ and a general power increase, though without specific instructions for the latter two. It emphasizes safety precautions, such as disconnecting power and inspecting the work area.

HF contesting is a rising aspect of amateur radio that can be enjoyed (at any level) throughout the year. There are HF and LF contests almost every weekend and on some weekday evenings. Learn how to take part in HF contests.

Ribbit is a novel digital text messaging mode for VHF/UHF communications for recreational and emergency use which radically increases the density of information transmitted by spectrum used. It leverages the computing power of the modern smartphone to increase the capabilities of any Handy Talkie without requiring any additional hardware or cable. A Ribbit message is fixed in duration at 1250 milliseconds. It is sent over audio modulation with a 2kHz bandwidth centered on 1.5kHz. It is preceded by 400ms of white noise to open analog squelch circuits.

Due to the nature of PSK it is imperative that you maintain a very clean signal. In this page you will find examples of a clean PSK signal and one with excessive splatter, and a short guide on how to properly adjust your transmitter to assure a clean trace

Reviving the spirit of early ham radio experimentation, the CW Flea is a contemporary Morse code transmitter. Utilizing an Arduino Nano, Si5351 clock generator, and innovative design, this open-source project offers simplicity, flexibility, and easy tuning for aspiring radio enthusiasts.

A simple 2-tone-generator for testing the linearity of SSB transmitters. This device is as simple as useful. With 2 transistors and an oscilloscope, it is fairly easy to test the linearity of your SSB transmitter. The 2-tone-method is a standardized test method that can be used to determine the maximum output and the amplification characteristics of a sideband transmitter.

Explaining ARRL Technical Reviews of Radios a brief tutorial on radio testing. The ARRL Lab tests radio equipment according to standardized test procedures, using calibrated professional test equipment. Info on transmitter and receiver tests

A transmitting antenna 2x15m, about 100 foot doublet antenna fed by a ladder line of about 600 Ohm. Article in Polish and English,

Operating from Banana Island, Sierra Leone (AF-037), the 9L2019 DXpedition by F6KOP and a ten-operator team used the callsign 9LY1JM from January 9-21, 2019. This detailed report covers the logistical challenges, including securing visas and licenses with local assistance from Mark 9L1YXJ and Gregory of Dalton’s Guest House. The team deployed monoband quarter-wave verticals on the beach and two Beverage on Ground (BOG) antennas for Europe/Asia and the USA, operating four stations simultaneously. Technical hurdles encountered included high tides submerging antennas, requiring repositioning, and persistent QRM between closely spaced stations, mitigated by doubling filters. CW signal irregularities at 30-32 WPM were resolved by PC and WINTEST restarts. A significant FT8 logging bug was identified and corrected with on-site software. Despite these issues, the team logged over 4,000 QSOs in the first 24 hours, averaging 5,000 QSOs daily, with a peak of over 6,000 in one day. Propagation varied, with excellent 160m conditions on January 12 yielding over 750 QSOs, and a later four-hour opening pushing the 160m total past 1,600. High bands were challenging due to low solar activity, but mid-bands provided intense pileups and rapid continent-wide contacts. The DXpedition concluded with nearly 50,000 QSOs, including a successful school QSO with Collège Doisneau de Sarralbe (57), managed by F1ULQ and F6KFT.

SNASharp is a free software application designed to work with scalar network analyzers compatible with NWT software from DL4JAL. It is used to measure and analyze the scattering parameters (S-parameters) of microwave devices. Provide several measurements and analysis tools including Smith chart, Polar plot, S-parameter tables, Transmission line calculator

Eaton provides a comprehensive suite of power quality solutions, ranging from compact single-phase isolation units to high-capacity megawatt sag correction systems. The resource details Eaton's engineering expertise in addressing diverse power quality challenges, emphasizing the distinction between DC resistance and apparent AC resistance under heavy current loads within AC power distribution systems. Specific **Marine-Grade surge protective solutions (SPD)** are highlighted, designed to safeguard critical safety and navigation equipment on vessels and rigs against unpredictable power transients in harsh environmental conditions. The company's commitment extends to providing appropriate solutions for critical power systems, ensuring quality installation. The site also features customer testimonials from entities like Federal Express, Kutztown University, J. C. Penney, and Fairchild Aircraft, attesting to the effectiveness of products such as 'The Protector' in preventing equipment damage and downtime.

This PA has been designed by Sergey EX8MLE and uses three Mitsubishi RD100HHF1 FETs, Frequency Range 70 to 72 MHz

The 222 MHz Transverter project, based on Zack Lau's (W1VT) original July 1993 QEX magazine design, provides an IF of 28 MHz for both transmit and receive paths. Rick Bandla (VE3CVG) contributed supplemental notes and construction details, including modifications to achieve 10 mW output power from an initial 4 mW PEP. The design incorporates three distinct boards: a Local Oscillator (LO), a Transmitter (Tx), and a Receiver (Rx), with an estimated parts cost of just over $150 CDN, significantly less than commercial kits. Construction involves both through-hole and surface-mount components, with specific guidance on mounting MAV and MAR devices, grounding techniques, and component selection. The project details include parts lists, schematics for the LO, Tx, and Rx, and board layouts. Troubleshooting advice emphasizes sequential testing, starting with the LO, then Tx, and finally Rx, using a 194 MHz and 222.100 MHz capable FM handheld for signal tracing. Further enhancements are discussed, such as an optional Tx driver stage to boost output to 100 mW and the potential modification of a Motorola Maxor 80 PA for 222 MHz SSB/CW operation. The resource also covers practical aspects like power attenuation pads for IF radios (e.g., FT817) and considerations for enclosure design, including repurposing a Maxor 80 case. Performance reports indicate successful 70 km contacts with only 4 mW output.

Exploring digital radio modes, the author rethinks how to adjust transmit and receive levels in WSJT-X. Despite effective communication using Yaesu's settings, a new procedure aims for better performance. For RX, set audio device levels to 100%, disable AGC, and adjust RF gain. For TX, enable "Remember power settings" and adjust power output to avoid ALC engagement. This method ensures reliable communication without signal degradation, enhancing dynamic range and minimizing noise.

A coaxial cable trap is a fundamental component in multiband antenna design, enabling a single radiator to resonate efficiently on multiple frequencies by electrically shortening or lengthening the antenna element. This project focuses on constructing such a trap for a vertical antenna operating on the 10 MHz (30m) and 14 MHz (20m) amateur bands, providing practical insights into its fabrication and integration. The article outlines the specific dimensions and winding techniques for the coaxial trap, emphasizing the use of readily available materials. It details the physical construction of the vertical element, including the mast and radiating sections, to achieve optimal performance across both target bands. The author shares personal experiences with similar trap designs, noting their effectiveness in previous horizontal dipole configurations. Key construction steps are illustrated with _original photos_, showing the assembly of the trap and its incorporation into the overall antenna structure. The design aims for a compact footprint, making it suitable for limited space installations while still delivering effective DX capabilities on the **30-meter** and **20-meter** bands.

The document details the construction and performance of a rotatable flag antenna designed for a small lot. The 7x14 feet flag, built with fiberglass poles and an aluminum hub, shows improved reception compared to the author's previous transmit antenna. Key components include a conventional transformer for impedance matching and a variable resistance termination system to optimize performance. Despite challenges like nearby objects affecting signal patterns, the antenna consistently provides better signal-to-noise ratios, making it a valuable addition for low-band listening in suburban areas.

This innovative antenna tuning unit (ATU) enables QRP operators to match their antennas without transmitting RF signals. Using a noise bridge technique instead of traditional transmit-and-tune methods, it achieves truly silent operation. The design incorporates an L-match network with switched inductors and variable capacitor, handling impedance matching from 3-30MHz. Operating from a 9V battery, it includes a built-in RF power meter and dummy load for QRP transmitter testing. The compact unit is particularly suitable for portable operations where minimal RF emissions during tuning are desired.

The Score Distributor facilitates real-time score forwarding for amateur radio contests, automatically transmitting data from various logging software to multiple online scoreboards. By configuring logging applications to send score data to the Distributor, operators ensure their current score is simultaneously represented on platforms like the _Contest Online ScoreBoard_ (COSB) and the Live Contest Score Server by R4WW. This system eliminates the need to choose a single scoreboard, providing broader visibility for participants. This utility enhances the competitive experience by allowing contesters to monitor their performance against other stations throughout an event. Observing real-time standings can provide significant motivation, particularly during periods of challenging propagation or when striving to maintain pace with club members or peers. The platform supports almost all major contest logging software, simplifying integration for a wide range of operators. Developed by WA7BNM, the Score Distributor was last revised on June 14, 2023. It aggregates score data, offering a unified point of submission that then disseminates the information, ensuring a **single point of entry** for broad scoreboard coverage and improving the dynamic feedback loop for participants.

This tutorial introduces and explains Smith Charts, and then gives an introduction to impedance matching. Smith Chart is a tool to visualize the impedance of a transmission line and antenna system as a function of frequency.

System Fusion is Yaesu’s implementation of Digital Amateur Radio, utilizing C4FM 4-level FSK Technology to transmit digital voice and data over the Amateur radio bands

Ham radio enthusiasts must prioritize lightning protection for their stations and homes to mitigate the risks associated with lightning strikes. Effective lightning protection involves dispelling myths, understanding the actual risks, and implementing proper grounding and surge protection. Key strategies include grounding all connections, protecting cables entering the station, and using surge protectors for power lines and control cables. Good grounding is essential for effective lightning protection.

he LoRa-APRS-iGate was developed in cooperation with the Austrian HAM Radio Association. With this software and the LoRa GW Shield, devices transmitting on LoRa, frequency 433 MHz can be integrated into the APRS network. The transmitter can then be displayed on the website https://aprs.fi.

The Lakeway Amateur Radio Club, identified by its callsign _W2IQ_, serves as a significant hub for amateur radio operations within the Lakeway Area. This organization demonstrates a strong commitment to regulatory compliance and amateur radio accessibility through its robust Volunteer Examination (VE) Team. As an ARRL-accredited entity, W2IQ facilitates online FCC amateur radio licensing examinations, providing a critical service for new licensees to enter the hobby. This infrastructure supports the growth of the amateur radio community by streamlining the licensing process, making it highly accessible to prospective operators. The club's technical contributions extend to fostering diverse operational interests, though specific repeater or APRS infrastructure details are not explicitly detailed. Their emphasis on licensing and education, particularly through remote testing protocols, highlights a modern approach to amateur radio entry. This focus on **VEC protocol coordination** ensures a consistent pathway for individuals seeking to obtain or upgrade their amateur radio licenses. The club also promotes engagement with various aspects of the hobby, indicating a broad interest in amateur radio activities and technical development within its geographic sphere of influence. Their dedication to supporting new radio amateurs underscores a foundational role in regional frequency management and community building.

Discover the best low band receive antennas for hams with limited space. Learn about the K9AY loop antenna and Shared Apex Loop Array, two alternatives to the traditional Beverage antenna. Understand the concept of Relative Directivity Factor (RDF) and compare the performance of different receive antennas. See how the Shared Apex Loop, patented by Mark Bauman (KB7GF), offers an RDF between 8 and 10dB. Find out how to optimize antenna performance and enhance your receive capabilities on 160, 80, and 40 meters. Explore the world of low band receive antennas with insights from WB5NHL Ham Radio.

This article details a ham radio operator’s experience setting up HF antennas in an antenna-restricted community. Initially using an AEA Isoloop magnetic loop for QRP PSK, the author later built an attic antenna system, including dipoles for multiple HF bands and a slinky dipole for 40 meters. The setup allowed for operation on six bands with acceptable VSWR. Despite space constraints and some compromises, performance was effective. The article highlights practical strategies, emphasizing experimentation and antenna modeling for optimizing performance in limited-space environments. A valuable guide for ham radio operators facing similar restrictions.

Showcasing German engineering, ANjo Antennen develops and manufactures a diverse portfolio of amateur radio and commercial antenna products. Their offerings span a wide frequency range from 1.8 MHz to 3000 MHz, emphasizing electrical and mechanical precision for longevity. The company actively participates in events like FUNK.TAG Kassel, providing opportunities for direct engagement and order pickup. ANjo's product line includes high-performance **Yagi antennas** optimized for Tropo and EME, along with multi-stacked Quad antennas designed for contest operations, featuring wide horizontal and narrow vertical beamwidths. They also produce circularly polarized satellite antennas, some with switchable LHCP/RHCP, leveraging their commercial satellite antenna expertise. Beyond amateur applications, ANjo provides flexible, custom antenna solutions for commercial sectors such as BOS, EMC measurements, and telemetry. Their commitment to quality is evident in the Premium-Line antennas, which utilize **1.4301 (V2A) stainless steel** for mast clamps and connectors, ensuring durability and corrosion resistance. They also offer end-fed HF multiband wire antennas, known for their compact footprint and discreet installation.

If you are having problems with RFI from Solar Panels this document from QST provides useful advice. According to this article it is possible to prevent and mitigate RF interferences, with your amateur radio equipment, by suppressing the RF either in the shack and to the solar power infrastructure.

This page by Lajos Hoss, HA8HL, provides a detailed guide on how to build a simple direct receiver using FT8QRP CAT control support. The author shares his experience in making QSOs with FT8, WSPR, and JT65 modes during the Covid-19 lockdown. Modifications to the VFO, transmitter design using BD329 transistor Class A amplifier, and the challenges faced in achieving clean output signals within legal limits. This project is interesting for those hams that are interested in experimenting with DIY transmitter projects and understanding CAT control support for various amateur radio modes.

Key clicks are generally undesired clicks or thumps generated by a CW transmitter as the key is put down or let up. How much does the rise time or bandwidth of a CW signal need to be limited to prevent other QSOs on adjacent frequencies from being annoyed by key clicks?

Cheap and simple fully automatic antenna switching that permit to automatically select the proper antenna based on transceiver status activity.

A real-time, responsive map view of APRS (Automatic Packet Reporting System) information, CWOP (Citizens Weather Observer Program), and other APRS-IS sources across the world. The N2RWE Real-time APRS Map leverages cutting-edge technologies and custom software to present a dynamic and user-friendly platform for visualizing Automatic Packet Reporting System (APRS) data. This web application aggregates real-time station locations from various public sources, offering a comprehensive view of APRS activity. It caters to both novice and experienced users by providing features like Maidenhead Grid maps, station lists, license plate searches, and advanced tools for geolocation, address lookup, and data analysis. Additionally, the platform integrates with Summits on the Air (SOTA) information, enhancing the experience for SOTA enthusiasts. By actively supporting the #APRSThursday net, the N2RWE Real-time APRS Map fosters a collaborative environment for the APRS community.

FreeDV uses an audio codec as a software based modem to decode and encode the voice and text data from your computer. The data is encoded and then is transmitted over the HF radio using AF signals that can then in turn be decoded by the receiving station.

This page provides information on designing a lightweight Moxon antenna for the upper HF bands and VHF. The Moxon antenna is a compact version of a 2-element Yagi with folded elements, offering good forward gain and a high front-to-back ratio. It is designed for a single band with a feed-point impedance close to 50 ohms. Hams can orient the antenna horizontally or vertically, with polarization following the configuration, affecting radiation patterns. The page allows users to generate radiation pattern plots, VSWR charts, antenna currents diagrams, and Smith charts for their antennas on different ground types, helping them understand antenna performance in the field.

This page show a list of repeaters in north america transmitting from 28 MHz to 29 MHz. The most of them are in the 29.620 to 29.700 frequency range. Some repeaters may be active and on the air while others may not

Filter Free is the shareware version of Filter Solutions and Filter Light. Filter Free is limited to 3rd order or lower low and high pass filters, 2nd order or lower band pass and band stop filters, and 10 tap or lower FIR filters, and does not include most of the advanced design capabilities of Filter Solutions and Filter Light.