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The SignaLink has been used with virtually every radio available, but the radio that is heard mentioned most often is the Yaesu FT-817

This low power transmitter is developed for ARDF exercising purposes but of course can be used as super QRP transmitter either. With 1 or 2 meter wire as antenna and a ARDF receiver with ferrite-rod antenna the range is about 100m but with better antennas and a 'real' receiver the range is probably much larger.

This is a 6 band receive only filter designed to protect your receiver front end and provide 45dB reject at the stop bands. This is a 6-band receive only filter designed to protect your receiver front end and provide 45dB reject at the stop bands. Stop band reject may be limited by the relay isolation. Worse case isolation is at 28 MHz or 35 dB or better. Relay K3/K8 protects the filter during transmit via the PTT line. A 25-50ms delay must be used between transmit and PTT. Do not rely on your radio to provide adequate delay with out using the PTT. You logging software must be set to allow a delay between PTT and time of 1st transmit. This filter will not work with VOX or QSK keying as you will damage the filter.

The **70cm Moxon Beam** project outlines the construction and testing of a compact, directional antenna for the 432 MHz band. G3XBM recounts his early 1980s experience with a 4W FM321 transceiver and a Jaybeam 48-element TV antenna, which provided a baseline for his later UHF antenna experiments. This project focuses on a simpler, yet effective, design for local and regional contacts, emphasizing ease of construction and practical field results over complex theory. The article details the specific dimensions and materials used for the Moxon rectangle, including 6mm diameter aluminum tubing for the elements and a PVC boom. G3XBM notes that the antenna was built for portable use, making it lightweight and easily deployable for field operations. The feedpoint impedance was measured at 50 ohms, ensuring a direct match without the need for an external tuner, which simplifies setup. Performance tests included comparisons against a commercial 5-element Yagi, revealing that the Moxon provided comparable forward gain and an excellent front-to-back ratio, crucial for reducing local QRM. The author's observations confirm the Moxon's reputation as a robust performer for its size, suitable for both fixed and portable 70cm operations.

OPCLOG provides a straightforward logging solution for amateur radio operators, enabling the systematic recording of contacts. The software primarily focuses on basic QSO management, allowing users to input essential contact details such as callsign, date, time, frequency, and mode. Its core utility lies in its ability to export log data in the _ADIF_ (Amateur Data Interchange Format) standard, which is crucial for interoperability with other ham radio applications and services. This ADIF export functionality facilitates the creation of personalized QSL cards, streamlining the process for operators who prefer custom designs over generic templates. The program's design emphasizes ease of use for individual station logging, rather than complex contest or DXpedition management. It offers a practical tool for maintaining a personal logbook, supporting the fundamental requirements for tracking contacts and preparing for awards. The software's simplicity ensures a low learning curve, making it accessible for operators focused on routine logging tasks.

W4ZT used this antenna for Field Day and other portable applications. He built them for all bands between 160 meters and 6 meters. You can make them easily using whatever wire you have available and make the insulators from scrap plastic

YO Yagi Optimizer by K6STI is an old MSDOS based antenna modelling software that has been very popular among ham radio community. YO.exe is still today used to optimize Yagi Antennas.

Various publications through the years have shown how the SWR measured on a shorted (or open) feed line can be used to calculate feed line attenuation

By Guy, de ON6MU, At VHF, both the 1/4-wavelength monopole and the 5/8-wavelength monopole antennas are widely used.

A Half wave antenna has a high impedance feed point. This can be matched using a 1/4 wave stub matching section and converts the 40m vertical into an L-shaped 20m J-Pole antenna. The 300 ohm feeder used for this purpose must be kept away from the ground.

NEC4WIN is a 32 bits commercial antenna simulation software based on MININEC3 developed by the Naval Ocean Systems Center in the 70s and 80s. It runs under Windows and can be used to simulate, analyze and optimize wire antennas, beams, verticals, etc. NEC4WIN has limitations. They are the same as Mininec3 on which the engine is based.

Investigates the gain characteristics of the **axial-mode helix antenna**, a widely used circularly-polarized antenna, by addressing conflicting claims in amateur literature regarding its performance. This article summarizes an extensive numerical modeling study using **NEC-2** to simulate approximately 10,000 different helical antenna configurations, systematically varying physical parameters like length and turn radius. The study consumed around 3,000 hours of compute cycles, with each antenna model utilizing between 600 and 1,400 segments for accuracy. The modeling data were rigorously compared against professional antenna literature, including experimental and theoretical work, revealing that the original Kraus formula for gain is often overly optimistic, predicting gains up to 4 or 5 dB higher than observed. Empirical expressions are provided for the maximum possible gain, Gmax(dB) = 10.25 + 1.22 L - 0.0726 L^2, and the optimum turn radius, Rmax = 0.2025 - 0.0079 L + 0.000515 L^2, both valid for antenna lengths (L) between 2 and 7 wavelengths. The research also notes that a half-lambda square groundplane performs nearly as well as an infinite groundplane, while radials incur a gain penalty of about 3.5 dB.

A 160 meter antenna with a base loading coil used to tune the two lower frequency segments of the band.

This program lets you cross connect Telnet connections and ComPorts or Ethernet. It can be used as a backup connection for PacketCluster nodes or to connect a CT network to a remote PacketCluster.

The Voice of America (VOA) website serves as a primary digital platform for its international news and information services, broadcasting in 44 languages. The resource presents a wide array of current events, geopolitical analyses, and cultural reports, reflecting a global perspective on news originating from the United States. Content spans various regions, including Africa, Asia, the Middle East, and specific country-focused reports from VOA's language services, such as VOA Uzbek, VOA Kurdish, and VOA Russian. The site features top stories, special reports, and sections like "All About America" and "VOA Explains," providing in-depth context on US-related topics and global issues. The VOA platform offers a continuous stream of updated news articles, covering political developments like government shutdowns, diplomatic relations, and international conflicts, alongside social and economic issues. It also includes sections for "Worth Watching" videos and "From VOA's Language Services," highlighting the breadth of its multimedia output. The content is designed to inform a worldwide audience, often presenting multiple perspectives on complex international events and US foreign policy, making it a significant reference for those monitoring global news and shortwave broadcast content.

HAMIC, is a program designed to simplify a number of calculations commonly used by HAMs. It is designed for the HAM radio hobbyist, but may be useful to others as well. HAMIC has a simple to use, but powerful graphical interface that allows solving simple circuits such as resistors in series or parallel, or more complex circuits such as L networks or T networks. As well, other calculations such as SWR and reactance conversions are supported. Windows shareware.

To save a little time from calculating and experime nting when winding toroid cores here a chart of the most commonly used cores

Description of the 80m antenna used at CN2WW in the ARRL-DX CW 2007

The Icom IC-746 is quite a popular HF/VHF multimode transceiver which has one shortcoming in its standard configuration when used to operate modes requiring good medium-term frequency stability.

Demonstrates the capabilities of CW_Shark, a dedicated 32-bit Windows application for Morse code operations. This software facilitates the analysis, decoding, and encoding of CW signals, providing hams with a versatile tool for various aspects of amateur radio communication. It supports four distinct modes: Decode Only, Keyboard QSO, Straight or Paddle Key QSO, and Straight or Paddle Key Practice, catering to different user needs from passive listening to active keying. Operators can utilize the Decode Only mode for signal analysis, while the Keyboard QSO mode allows for text-based interaction. The Straight or Paddle Key QSO mode offers a direct interface for traditional keying, enabling real-time communication. For skill development, the Straight or Paddle Key Practice mode provides a structured environment to hone Morse code proficiency. CW_Shark integrates essential functions for CW enthusiasts, supporting both learning and active participation in Morse code exchanges. Its focused design aims to assist operators in mastering and enjoying the art of _CW communication_.

F5AD describes the ATV repeaters in the south of France, and methods, frequencies, modulations used in ATV in France and in Europ. (French and English)

It is a application which can be used for troubleshooting CB radio faults, by giving a graphical display of the normal operating frequencies generated by various parts of the CB radios circuits, it can help you identify if a frequency is incorrect or even missing. Another good use for this software is simulating possible frequency expansions, as it allows you to choose any frequency that the PLL is capable of generating, so you can see what the radio will allow you to get !

An unused 5v supply connection allows an electret condenser microphone element to be used in place of the standard dynamic element. Modification by M0UKD

Despite the title referencing the callsigns 3C5J and MW0BRO, the content of this resource focuses entirely on the _Cleddau Computer Clinic_, an IT services company operating in Pembrokeshire since 1999. The site outlines a broad range of computer-related services, including custom-built new PCs starting from £399, sales of used systems, and comprehensive repair and upgrade options for existing units. Services extend to anti-virus and spyware removal, system installation, and broadband connection setup. The clinic also provides tuition for hardware and software applications, website design, and video to DVD transfer. They specialize in both fixed and wireless network solutions, enabling clients to share files and broadband connections efficiently. Repairs can be conducted either in their workshop or at the client's home or office, offering flexibility. For situations where on-site repair is not feasible, the Cleddau Computer Clinic offers a temporary replacement computer service. This includes transferring essential data to minimize disruption, a practical approach for local businesses and individuals in areas like Pembroke, Milford Haven, and Haverfordwest.

FAR Circuits is exclusively a manufacturer of Printed Circuit Boards for electronic projects that are used by the Amateur Radio and electronic hobby enthusias

This article describes a project of asymmetrical hatted vertical dipole, a portable antenna that can be used for field day operations, sota, campings or even for fixed installations. This is a freestanding 20-10m antenna that is really easy to build, easy to tune and relatively easy to carry.

An home made QRM Eliminator project based on the WA1ION original design, used to remove QRN generated locally by an halogen lamp in Dutch

How to build a super AM antenna, These plans have been used by many people, with good results.

Testing the tv reception mod for the us version. tv reception was disabled on the us version because of the possibility of it being used while driving.

Details Guglielmo Marconi's foundational contributions to radio communication, highlighting his 1898 Patent **7777** which introduced tuning circuits for independent simultaneous communications. Chronicles the historic transatlantic reception of the Morse code letter 'S' on December 12, 1901, from Poldhu, Cornwall, to St. John's, Newfoundland, a distance of over _3,500 kilometers_. The exhibit showcases early Marconi 10-inch spark transmitters, identical to those used on the _Titanic_, alongside Canadian Marconi crystal detector models. It also features high-end commercial receivers like the IP501, weighing **87 pounds** and originally priced at $595.00, demonstrating the robust construction and technological advancements of the era.

A combination of Fldigi and Flmsg for portable devices running Android used for NBEMS

Group with thousand of memebers focused on NVIS antenna

A short dipole wire antenna for 40 meters band. It is a folded dipole that do not make use of coils and can be used either in horizontal or inverted V configuration

The document provides a comprehensive overview of baluns, which are devices used to connect balanced loads, like dipole antennas, to unbalanced inputs, such as coaxial cables. It covers various types of baluns, including voltage and current baluns, and their design, construction, and testing. The text discusses the importance of baluns in preventing RF currents on coax shields and their applications in Ham radio setups. It also includes practical advice on selecting and using baluns based on antenna impedance and power ratings, along with detailed performance evaluations and construction tips for different balun configurations.

The Collins TRC-75 autotune linear amplifier, owned by JF2SVU, is presented with a focus on its internal modifications. This QRO amplifier utilizes three 4CX250 tubes in parallel for its final stage, delivering 1 KW output power. Notably, the amplifier achieves full power with only 100 mW of RF input, a characteristic often associated with Collins designs. The original 400 Hz power supply has been converted for easier shack integration, and the entire RF and power supply sections have been rehoused into a compact, clean enclosure. The control unit, positioned above the amplifier, features three meters for individual vacuum tube IP monitoring and a multi-meter on the right. A dedicated 7 MHz receiver, recently completed, is also part of this integrated system. The autotune functionality means the main amplifier unit only requires connections for power, control, and coaxial cables, simplifying its operation. Key components like the 4CX250 tubes and NF capacitors are visible, along with the gearing mechanism for the final tank circuit. A timer and relay system manages high-voltage delay and cooling fan off-delay, although the cooling fan's airflow is noted as somewhat insufficient. A central volume control, which experienced a contact issue, is also highlighted.

This online guide details the microphone pinout for the Kenwood TR-7950 transceiver, specifically addressing the wiring configuration for a dynamic mobile microphone with a **500 Ohm** impedance. It provides a pin-by-pin breakdown for the 6-pin microphone connector, identifying the function of each active pin. The resource specifies that Pin #1 is for the microphone audio (white wire), Pin #2 controls the _PTT_ (black wire), Pin #3 activates the memory down function (blue wire), and Pin #4 controls the memory up function (red wire). Pin #6 is designated as the ground connection, while Pin #5 remains unused in this configuration. The document focuses on the physical wiring necessary to restore microphone functionality to the Kenwood TR-7950, a transceiver capable of **45 watts** output on the _2m band_. It directly addresses the technical challenge of re-establishing correct electrical connections after microphone wires have been disconnected from the connector. The information facilitates proper microphone operation for simplex QSOs and other voice communications. DXZone Focus: Online Guide | Microphone Pinout | Kenwood TR-7950 | PTT Wiring

MSHV is a free windows and linux multimode software that support weak signal digital modes like MSK144 MSKMS JTMS FSK441 FSK315 ISCAT JT6M FT8 FT4 JT65 PI4 amateur radio modes. MSHV features several interesting features including the Multi Answering Auto Seq Protocol, allowing multiple signal transmissions to be used during dx peditions.

Operating a specialized DX cluster, this service provides real-time DX spots exclusively from stations confirmed to be _Log of The World_ (LoTW) users. This unique filtering mechanism allows DXers to prioritize contacts with stations that are highly likely to upload their logs to LoTW, streamlining the process of achieving confirmed DXCC or other awards. The cluster aggregates data from various sources, presenting a focused view of active LoTW participants across multiple bands. By narrowing the scope to LoTW-active stations, the platform significantly reduces the effort required for QSL management, as users can confidently pursue contacts knowing a digital confirmation is probable. This targeted approach is particularly beneficial for contesters and DXpedition chasers aiming for rapid award qualification, offering a strategic advantage in identifying viable contacts. The service supports both web-based access and traditional telnet connections, ensuring broad compatibility for amateur radio operators. It processes thousands of spots daily, with a focus on delivering accurate and timely information relevant to LoTW users, facilitating more efficient and productive operating sessions.

At the moment the most used program is UA1AAF. It is an excellent program written by Boris, UA1AAF, to handle ARI International DX Contest. It can simulate K1EA or N6TR workings; it will be possible to connect the RTX to the computer using a standard interface in such a way as to transmit directly in CW from the keyboard; most of the controls are like K1EA's CT and N6TR's TR ; on line help provides almost all the information necessary for using the program. Is possible to insert QSO after the contest. An appropriate utility in included for conversion in ADIF format. The program is very small and therefore works without any problems on any IBM compatible computer with DOS 3.3 and over or Windows 95/98.

A circuit which had been used in many other application before. The configuration described here is optimized for IPHONE/radio operation.

how to make a gamma match for a antenna. The Gamma match is the most used matching device used for yagi beams.

Ferrite rod antenna or aerial, a form of RF antenna that is widely used in RFID and transistor radio applications.

The Folded Dipole is not used much amongst Radio amateurs, probably due to the fact that this antenna uses twice as much wire as a single-wire dipole.

A Windows based Spectral Analysis/Receiver Program primarily used with the SDR-IQ, SDR-14 , SDR-IP, RF capturing hardwares

The Super Check Partial database files provide a list of callsigns used by active contesters. The data comes from Cabrillo logs contributed by contesters themselves. Contributed logs from the past 24 months are used to create the database. These logs are combined and filtered so that they result in a fairly good (but not perfect) list. The files do not contain any QSO data, such as state, CQ zone, Maidenhead Grid Locator, etc. The dta files can be used with CT, WriteLog, TRlog, SD, N1MM Logger, NA, Win-Test, and others

This ia a home built Magnetic loop antenna which was used by G3BGR, indoors on 7,10 and 14Mhz. The basic idea was in Radcom 1986

ARRL's Logbook of the World (LoTW) system is a repository of log records submitted by users from around the world. When both participants in a QSO submit matching QSO records to LoTW, the result is a QSL that can be used for ARRL award credit.

The MobileLog program is a specialty logging program designed for mobile amateur radio operators. It has been designed to allow quick entry of important information regarding QSOs. The software is primarily concerned with the logging of U.S. county information, which may be used to help work toward awards such as the USA-CA award for working all counties in the U.S.A. The data from this program may be imported into your general logging software. This sofware exports data in the ADIF (Amateur Data Interchange Format) and CSV (comma-seprated variable)

This interface is intended to be used with all the popular digital modes like PSK31, RTTY, Olivia, etc., which modulate a continuous carrier.

Here we have a ground plane antenna mostly used for 144, 222, 440 Mhz. Its one of the simplest antennas to make. New hams can build this with little to no experience in antenna building.