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A long picture gallery of a homebrew hexbeam antenna project

Ham Radio Vertical HF multiband antennas manufacturers based in Spain

SCRRBA is a volunteer organization providing coordination of a number of heavily utilized amateur radio frequency bands in Southern California.

Amateur radio antennas manufacturer, produce multiband and monoband high performance yagi antennas and vertical antennas based in Poland

KV5R review of the Icom 706MkIIG

A quarter wave antenna with dimensions for uhf and vhf bands

Introduction to Shortwave Antennas. Understanding Shortwave Radio Listening and Antenna Design and Construction

A collection of drawings of most popular wire antennas for hf ham radio bands

A page descibing the principles of OCF antennas also known as windom antennas by DJ0IP

Magyar Radioamator Szovetseg

This method of construction can be used on most UHF through \"low\" microwave Yagis, and is especially useful for the 33, 23 and 13 cm bands

SCCARA was formed as a general interest amateur radio club in 1921 and became a non-profit corporation in 1947.

Taking the Raspberry Pi 2 for a Test Drive with GNU Radio. Installing GNU Radio and receiving aircraft radar with a USB TV tuner

Comparing the ICOM IC-7600 and the Yaesu FTDX-3000

13,8 v / 1 A power supplies using the UA78 series by ON6MU

9600 Baud modification on the Kenwood TM441 by ON6MU

Projects you can build, an amplified shaped sine-wave oscillator

Introduction to Raspberry Pi and possible usages in amateur radio, PDF presentation.

Constructing a high-power 70cm solid-state amplifier presents unique challenges, particularly when aiming for 500 watts output using modern LDMOS devices. This resource details the author's experience building a 70cm amplifier based on a _Freescale MRFE6VP5600H_ transistor, initially from an RFHAM kit. It meticulously outlines the necessary modifications to achieve advertised performance, including optimizing input and output matching, correcting bias circuitry, and ensuring proper output balun connections for stability. The author shares specific adjustments, such as trimming the prototyping board for better transistor fit, drilling additional mounting holes for improved heat sinking, and replacing original matching capacitors with a single _20pf MIN02 metal mica_ for superior output. A critical fix involved jumpering gate decoupling pads to balance the push-pull transistor halves, which increased output to 580W and improved IMD. The resource also highlights a crucial correction to the output balun connection, initially reversed in the _Dubus_ article schematic, which resolved intermittent stability issues. Test results are provided, showing input power, output power, and drain current at 50V, demonstrating the amplifier's performance after modifications. This practical account offers valuable insights for hams undertaking similar high-power UHF amplifier projects, especially those working with LDMOS devices and kit-based constructions.

PTT and souncard interface for the kenwood TM255 and TM455

Is a group who enjoy gathering together to practice the hobby of Amateur Radio.

SARA is a volunteer club dedicated to furthering the advancements of Amateur Radio

A simple free running oscillator oscillating at the receiver\'s IF (intermediate frequency) beats with the incoming signals in either CW or SSB and the resultant audio frequency goes to the AF amplifier.

A moxon antenna for 2 meters band featuring 6 dBi and a F/B of 30 dBi

Random Length Wire Antennas by WOIPL

Presents Eagle Stainless Tube & Fabrication as a certified distributor specializing in various tubing products essential for antenna construction and other amateur radio projects. It details their offerings, which include aluminum tubes in fractional, metric, and heavy wall specifications, alongside stainless steel bar stock in round, square, and flat profiles. The resource highlights the availability of a diameter sizing chart and direct contact options for specialists, indicating a focus on providing specific material dimensions and expert support for custom fabrication needs. The company emphasizes its role as a supplier of raw materials, crucial for hams engaged in DIY antenna builds or structural components for their shacks. Their inventory supports the precise mechanical requirements often encountered in radio frequency engineering, where material strength, weight, and corrosion resistance are critical design factors for outdoor installations. The site primarily serves as a product catalog and contact point for sourcing specialized metal tubing and bar stock, providing technical specifications and material grades relevant to robust amateur radio infrastructure.

There are many designs for building preamps each with their own advantages and disvantages. In this PDF Article author reviews several different types.

A vehicle mounted portable antenna mast.

Serbia montenegro

Approximately 2.8% annual decline in Australian amateur radio licenses was observed over the five years leading up to 2002, a trend that prompted further analysis of the country's amateur population. This resource examines licensing statistics and demographic shifts within the Australian amateur radio community between 1998 and 2007, utilizing available data to identify patterns in license issuance and renewal. The study focuses on **population trends** and the underlying factors contributing to changes in the number of active **amateur radio operators**. It provides insights into the health and growth trajectory of the hobby in Australia during this specific period. Understanding these demographic shifts is crucial for clubs, regulatory bodies, and equipment manufacturers to adapt strategies and foster engagement.

Optimizing weak signal reception on the HF bands, particularly in the presence of strong local QRM, often necessitates specialized receiving antenna systems. This resource details the _HI-Z Antennas_ product line, focusing on phased vertical arrays designed for superior noise rejection and directivity. It covers components such as the 4-Square and 8-Element array controllers, which allow for rapid switching of receive patterns, and dedicated low-noise preamplifiers to improve system sensitivity. The site also presents various bandpass filters, crucial for mitigating out-of-band interference and enhancing the dynamic range of the receiver. The HI-Z systems are engineered to provide significant front-to-back and side rejection, often yielding **20-30 dB** of attenuation to unwanted signals, which is critical for DXing and contesting. Users can achieve a notable reduction in local noise, allowing for the discernment of signals that would otherwise be buried. The array controllers facilitate quick pattern changes, enabling operators to null out interference or peak weak signals from distant stations, effectively extending the reach of their receive capabilities by improving the signal-to-noise ratio.

A dual band delta loop antenna resonating on 30 and 40 meters band using a single wire for the top slopers on both 30 and 40 meters and does not need any balun

A high quality broadcast transmitter big enough for a medium town

Excellent article and guide to choose the best RF power amplifier that fit your needs by ON4SKY

CAARA, an ARRL affiliated club, operates the 2 meter W1GLO repeater on 145.130 MHz

Antenna element holders, antenna parts, aluminium tubing, fiberglass tubing, connectors and antenna mounts and hardware by Eidolon AS

The Pikes Peak FM Association is a nonprofit, amateur radio VHF/UHF group which operates and maintains VHF and UHF communications facilities serving the Colorado Springs and Pikes Peak region.

Basic guidelines for proper placement of an amateur radio mobile antenna

Amateur, scanner, wi-fi and land mobile antennas and accessories online store

Established around 1968, the Wichita Amateur Radio Society (W.A.R.S.) N5WF provides a central hub for amateur radio operators in the Wichita Falls, Texas area. The society actively supports local ham radio interests, fostering community engagement and technical development among its members. W.A.R.S. is known for its commitment to public service communications and promoting the amateur radio hobby through various activities and educational initiatives. The society's activities often include field operations, technical presentations, and participation in emergency communications drills, which align with its mission to support the amateur radio community. Members frequently engage in _DXing_ and _contesting_, sharing their experiences and knowledge to help others improve their operating skills. The club also maintains local repeaters, providing essential infrastructure for regional communications.

a forum for extra class operators to discuss cw, and extra class operation without the usual friction debates.

A sweep generator that produces a sawtooth waveform which sweeps the oscilloscope beam from left to right via its X input, and simultaneously the VCO frequency.

A moxon antenna project by KD6WD

This document is a must read for anyone considering building a good low cost HF multi-band antenna system. The author combine in this document four important ingredients to produce simple but effective antenna system, like antennas of non resonant length, line attenuation, the transmatch and the balun

Operating as a local amateur radio club, the Wireless Association of South Hills (WASH) provides a community hub for hams in the Pittsburgh, PA area, identified by the N3SH callsign. The club engages in a range of activities including the Annual Field Day, the PA QSO Party, and a 2 Meter Contest, fostering participation in various aspects of the hobby. WASH also supports local ARES/RACES efforts, highlighting the critical role of amateur radio in emergency communications during disasters, and facilitates ARRL/VEC exam sessions for new licensees. Beyond contests and emergency preparedness, WASH hosts club picnics and an annual hamfest, promoting social interaction among members. The club maintains VHF/UHF repeaters, which are essential for local communication and extending range for members. Regular activities include a Monday evening WASH NET at 8:00 PM, providing a consistent on-air gathering point. The club's focus on both recreational and public service aspects of amateur radio, from making new friends to providing vital disaster communications, underscores its comprehensive approach to the hobby.

This page describes how to set up RaspBerry Pi Linux system with already configured AX.25 softwares on SD or micro SD cards

The current, the voltage, the impedance, the bandwidth, the polarization, and how the earth influences the famous radiation pattern.

A virtual museum of Collins Radios

About DRM, the DRM standard, emission types, upfrading your old HF RX to DRM