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RemAud is a Voice over IP (VoIP) application primarily designed for two-way amateur radio remote control over the Internet. RemAud uses streaming-audio technology in a client-server architecture. It features high radio sound quality, low latency, low bandwidth and very low CPU usage by DF3CB

DF3CB site, contesting, and software BV is a professional freeware software for the QSL Management and Label/QSL Printing under Windows developed and distributed by Bernd Koch, DF3CB, since 1989. It is mainly designed for the contester and QSL manager with high QSL quantities but useful for all other QSL'ing purposes as well. Includes logging features

This online tool will convert any street address into latitude and longitude and vice-versa by executing queries to several online mapping services like googlemap geocoder maporama terraserver and more by Stephen P. Morse

Are you experiencing very high SWR with the 10M Modification to Ameritron AL-811 amplifier ? This is a good forum topic to fix this problem.

This database contains data on thousands of tubes

TL922 Service manual

Build an HF antenna tuner by VK5AJL

A vertical antenna specifically designed to work with the 80 meter CW beacon keyer

A _Topfkreis_ antenna, also known as a "bicycle pump" antenna, is presented as a simple vertical design for the 70 cm band. This variant of the J-pole antenna is notable for not requiring a ground plane, simplifying deployment. The construction details specify using aluminum tubing for the radiating element, with precise measurements for the quarter-wavelength outer tube (32 mm diameter) and the three-quarter wavelength inner sliding tubes (10 mm and 8 mm). Feeding is via a 50-ohm coaxial cable connected 90 mm from the base of the central tube. This design can achieve a gain of **4 to 6 dB** when properly tuned using the adjustable radiating element. The article details the fabrication of a critical aluminum washer, suggesting a method using a hole saw and a drill press as a lathe for precise adjustment. The illustrated example is specifically for the 70-centimeter band, and the author, Pop, clarifies construction points in the comments, including material choices and assembly techniques, ensuring a robust build for VHF/UHF operation.

A simple online folded dipole antenna calculator

The 60 Watt linear amplifier is simple all solid state circuit using power mosfet IRF840.

Operational testing of a 10.07-meter portable HF vertical antenna, constructed from telescoping aluminum tubing (36, 32, 22, 17 mm diameters), yielded SWR measurements below 1.5 across multiple bands. Initial trials on 14.150 MHz showed an SWR of 1.6, while 7.075 MHz was problematic. Subsequent adjustments, including a 13 cm extension to the radiating element, improved performance, enabling operation on 6, 15, and 40 meters without a balun, and adding 12 meters with a balun. The design prioritizes portability, allowing transport in a standard vehicle and single-person deployment. Four 10.07-meter radials are connected at the base to enhance ground plane effectiveness. The article details the mechanical assembly, including custom adapters for tube transitions and a PVC sanitary tube sleeve for base insulation, ensuring robust field deployment. Final SWR measurements, documented with an _MFJ-259_ antenna analyzer, confirm operational ranges: 6.800-7.500 MHz (SWR < 1.5), 20.800-22.500 MHz (SWR < 1.5), and 48.800-51.500 MHz (SWR < 1.5) without a balun. With a balun, the antenna achieved SWR < 1.5 on 13.750-15.000 MHz and 24.890-28.350 MHz, demonstrating its versatility for portable _DXpeditions_.

About dummy loads, what are they and how to build one

Calculate design for a quadrifilar helicoidal antenna

Remotely controlled antenna switch that can switch between 5 antennas

This free program by SP7DQR is designed to print QSL Cards using Mail Merge Tool in MS Word from ADIF file.

Online log for 5V7TT Togo dxpedition 2010. Offer QSL request service.

The page provides a utility to record QSOs for amateur radio operators, allowing them to send the recorded signal back to the other station. It addresses challenges with VOX capability in radios and offers solutions for different radio models.

MSDOS astronomical clock and celestial tracking program with navigation features

Slot antennas explained

Online helix antenna designer, calculate size of helix antennas online

Enables users to convert plain text into _Morse Code_ and, conversely, decode Morse sequences back into readable text. This web-based utility provides a straightforward interface for rapid translation, proving useful for both learning and practical application. It processes input efficiently, displaying the corresponding Morse or text output instantly. Operators can leverage this tool for generating practice copy or for deciphering received CW signals, making it a handy resource for those honing their code skills. The translator handles various character inputs, converting them into standard International Morse Code elements. This simple utility supports quick lookups and real-time conversions, facilitating a better understanding of CW structure and timing. It operates entirely online, requiring no software installation.

Discussion on how properly drive and tune athe Ameritron AL-811 power amplifier

A solid state linear based on EB104 Motorola Engineering Bulletin by Helge Granberg. It uses 4 MRF150 FETs in push-pull parallel to acheive 600 Watts from about 6 Watts drive

Tuning the Solarcon Antron A-99 antenna for 20 meters band

This description is taken from the Pete's W2PM posting into Topband reflector.

A project of a vertical and wires that generate a multiband antenna for 28 14 10 and 7 Mhz in french

Info about Yaesu VX-8R by APRS Wiki

Topic regarding a new 1KW HF power amplifier with 2x GI7B

Sporadic-E clouds location and estimated MUF real time map by DXMAPS

E4X Palestine On-line Log 2010 dxpedition

List of modifications for the kenwood TS-50

A Quagi antenna project with pictures and dimensions for a UHF Quagi antenna

Demonstrates the construction and measurement of a single-turn HF receiving loop antenna, built from common materials like electrical conduit and lamp cord. The resource details the physical dimensions, including a 4-meter circumference, and calculates the theoretical inductance at approximately _6.4 uH_. It outlines a method for determining resonant frequencies across the 4-17 MHz range using a _C Jig_ and a _VR-500 receiver_, coupling the loop with a ferrite ring. The article also discusses the impact of receiver coupling on the loop's Q factor, noting a degradation in sharpness due to the transformer's reflected impedance. Analyzes the observed resonant frequency patterns, highlighting an unexpected rise in the loop's effective inductance at higher frequencies, particularly above 13 MHz. While some increase is attributed to distributed capacitance, the rate of rise suggests further investigation. The experimental setup provides practical insights into the challenges of maintaining high Q in simple receiving loops and offers a comparative reference for other homebrew antenna projects, such as those by _VK2TPM_.

Grig is a simple Ham Radio control (CAT) program based on the Ham Radio Control Libraries (Hamlib). It is intended to be highly generic presenting the user to the same graphical user interface regardless of which radio is being controlled.

An home-brewed morse code CW filter with a central frequency of 800hz and a variable bandwidth from 230hz to 26hz by F5RDH in french.

Modifications and messages about the Yaesu FT-450

Basic information on the folded dipole antenna

Choosing a vertical antenna. Buying guide to amateur radio HF vertical antennas by Bencher inc

How could we share the Beverage antennas on more than one station using this homemade remote antenna switch, a project by TK5EP

A simple RF power amplifier initially designed for 40 meter band can work on 10 15 20 40 80 meters

World data center for the sunspot index

The UK amateur radio licensing scheme features three distinct tiers: Foundation, Intermediate, and Full, each granting specific operating privileges. For instance, the **Foundation Licence** permits a maximum of 10 watts output power on most allocated bands, with restricted band access. The Intermediate Licence allows up to 50 watts, while the **Full Licence** grants access to the maximum UK legal power limits and all available amateur radio band allocations. UK call sign prefixes and formats provide insights into the licensee's class and the approximate issuance date. For example, M3, M6, and M7 prefixes with three letters denote Foundation Licences issued from 2002, 2008, and 2018 respectively. Intermediate Licences, often starting with "2E0" or "2E1" followed by three letters, were issued from 1991 onwards. Full Licences encompass a broader range of prefixes like G2, G3, G4, G0, and M0, with varying letter counts indicating different historical license classes and issuance periods, such as G3 plus three letters issued between 1946 and 1971. Special prefixes like GB are reserved for repeaters, beacons, data mailboxes, and special event stations, with specific numerical sequences (e.g., GB3 for repeaters, GB7 for data repeaters/mailboxes) indicating their function. Optional prefixes such as GC, GD, GI, GM, and GW denote specific UK countries (e.g., Wales, Isle of Man, Northern Ireland, Scotland, England) and can also signify club stations.

Nowdays lots of people are putting up antennas to either beam in different directions at the same time or just to stack them and get a lower angle of radiation. Use this stackmatch to match you array.

This is an 80 metre dipole that fits in a small spac

A homemade VHF/UHF vertical antenna made essentially with RG58 coax cable, with a 9 turns choke balun to prevent the shield acting as a RF Radiator.

VHF & Up Software management, Station Log and maps, in English

If your doing any home brewing gear for ham radio its a great idea to have a dummy load. This will to your radio be the perfect antenna...it will never radiate but your radio sees a perfect 50 Ohm impedance.

On-line Log search for 5U5R DX Pedition to Niger 2017

Raspberry Pi WebSDR Receiver Project running SoftRock Lite ii Receiver (40m) and Raspberry Pi Model B