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A list of links to semiconductor manufacturers, including direct links to their datasheets index page

issued by the members of YO2KJI

A Shielded Low Frequency Loop Antenna, allows Simultaneous Transmission and Reception at the Same Site.

Scanning the Top of Utah – Reband Update, Trunk Scanning – Channels & Talk Groups , Conventional Scanning - Frequencies, Scanning Aids

SMCC Amateur Radio Club - K9ONA

This page is about the Ionosphere, how it was discovered, what it is, and what you can do with it.

A web site dedicated to HamNet in New Zealand

Reference site of the HAMVOIP AllstarLink AllstarLink provides hams with a means of connecting radios, repeaters or simplex links, over the internet. It is built upon the asterisk open source PBX and runs on Linux

Amateur Radio Amateur Radio Manuals & Books Computer Books & Programs Computer Hardware Rare & Hard to Find Books amateur radio,electronics ,electronis parts,tubes, amplifiers,towners, beam antennas and more

YOTA Youngsters On the Air Facebook public group

The vOICe Learning Edition can be used in combination with a regular oscilloscope, allowing blind users to hear any oscilloscope trace.

The purpose of this blog is to help new hams and promote amateur radio

W3FPR fixed level AF output fot the Elecraft K2

The BikeLoop antenna project details the construction of a double magnetic loop antenna optimized for VLF frequencies, specifically around 136 kHz. This innovative design incorporates two orthogonal loops, which significantly enhance reception capabilities. Key construction hints include utilizing lightweight bicycle rims for the antenna structure, making it easy to transport and set up in various locations. The document provides valuable mathematical and electrical insights into the antenna's performance, alongside practical reception tests conducted in the Italian Alps, showcasing its effectiveness in capturing various VLF signals, including Sferics and FSK transmissions. Proper setup is crucial for optimal performance. The project emphasizes the importance of grounding and avoiding interference from nearby electrical sources. The reception tests revealed the antenna's ability to capture a range of signals, demonstrating its practical application for enthusiasts interested in VLF reception and antenna experimentation. Overall, the BikeLoop serves as an excellent starting point for those looking to explore the world of VLF frequencies and enhance their antenna-building skills.

A review of the 30 meter MonoGap Antenna. This review covers from the unboxing go the Gap product, the assembly of the elements, the test and tuning phase and a performance report during the years

A Simple Serial and Sound-Card Interface for the Yaesu FT-857D using an FT232R USB-to-serial bridge chip.

The DIY 137 MHz WX SAT V-dipole antenna project details the construction of a specialized antenna for receiving weather satellite transmissions. It provides specific dimensions for the dipole elements, designed for optimal reception around the 137 MHz band, which is commonly used by NOAA and Meteor weather satellites. The resource outlines the materials required, such as aluminum tubing for elements and PVC for the support structure, along with the necessary coaxial cable and connectors. The article presents a clear, step-by-step assembly process, including how to form the V-shape and connect the feedline. It emphasizes practical considerations for mounting and weatherproofing the antenna for outdoor deployment. The design focuses on simplicity and effectiveness for amateur radio operators interested in satellite imagery. Key aspects include the precise angle of the V-dipole and the lengths of the radiating elements, which are critical for achieving the desired circular polarization response for satellite signals. The resource includes photographic documentation of the construction phases and the final mounted antenna.

A quarter wave vertical omni-directional antenna for 7 MHz. Formulas for dimensions in feet and meters are provided. Ideal radial angle is between 35° and 45°. Velocity factor (Vf) varies based on coax type.

Heinrich Hertz was the first to send and receive radio waves.

A review of the Alpha 87-A power amplifier by WD0M

Real-time solar activity page at SpaceWeatherLive.com display sunspot regions, indicating sunspot numbers of with manitude class, Solar Flares and a list of daily events on the sun.

The South Essex Amateur Radio Society was formed in 1983 in UK

Product information, resources, enhancements and links of the popular ICOM IC-756PRO III

DK7IH QRP transceiver for 14 MHz. This small and compact home made transceiver with a max power output of 5W, the VFO module is based on the clock oscillator chip Si5351A by Silicon Labs ATmega168 and OLED 1306

Fast Scan Amateur Television in Alabama, Arizona, Northern California Southern California, Georga, Illinois, Indiana, Kentucky, New Mexico, Nevada, Texas, Washington, Delaware, Maryland, New Jersey, and Pennsylvania

A cavity backed antenna is a practical slot antenna tipically used in microwave applications

Jamboree On The Air web site from denmark

The Gwinnett Amateur Radio Society (GARS) is an ARRL special service club serving Gwinnett and the surrounding counties in Northeast Metro Atlanta. We are a diverse club with interests spanning all interests in amateur radio.

Clarifies the intricate process of calibrating the _Elecraft K2_ dial, addressing common user challenges and lively discussions on the Elecraft reflector. Wilhelm, W3FPR, dissects the K2's PLL synthesizer design, chosen for its low phase noise, kit-friendly duplication, and cost-effective components. The resource emphasizes the critical role of the 4000.000 kHz reference oscillator's accuracy during CAL PLL, CAL FIL, and CAL FCTR functions, noting its dependence on temperature and crystal stability for optimal performance. Explaining the K2's frequency display, the document reveals it relies on microprocessor-driven look-up tables generated by CAL PLL for VFO values and CAL FIL for BFO values. In SSB and RTTY, these combine, while CW and CWr modes also factor in the sidetone pitch. The author details inherent limitations, such as the 10 Hz increment resolution of the dial and varying PLL step sizes—from 3 Hz on 160 meters to 10 Hz on 10 meters. BFO increments range from 20 to 35 Hz, collectively limiting practical dial accuracy to within **20 Hz** with diligent effort, or **30 Hz** for a slightly less demanding task. The guide outlines a four-step calibration procedure: setting the reference oscillator, running CAL PLL, running CAL FIL, and setting all BFOs. It highlights the _N6KR Method_ as a particularly easy and accurate approach, requiring only the K2 and a known frequency source like WWV for zero-beating, eliminating the need for external test equipment.

The White Rose Amateur Radio Society website provides information on amateur radio activities in Leeds and West Yorkshire, including details on meetings and membership. Contact details for the membership secretary are also available.

Amateur radio repeaters, often designated by an "R" number like _R6_ or _R5_, serve as crucial infrastructure for extending VHF/UHF communications range. This resource from Essex Ham explains the fundamental concept of a repeater, detailing how it receives on one frequency and simultaneously retransmits on another, typically with a 600 kHz offset for 2-meter repeaters. Understanding the input and output frequencies, along with the required CTCSS tone, is essential for successful access, ensuring your signal is processed and relayed across a wider service area. The article clarifies the importance of using the correct _CTCSS_ (Continuous Tone-Coded Squelch System) tone, often referred to as a sub-audible tone, to activate a specific repeater. It also touches upon the concept of _simplex_ operation versus repeater use, highlighting the benefits of repeaters for mobile and handheld transceivers. Proper operating procedures, such as listening before transmitting and keeping transmissions concise, are emphasized to maintain good amateur practice on shared repeater assets.

If you want to have a closer look at the weather, you can download software and visually display data.

Wireless Society of Southern Maine Projects, instructions and photos for many ham radio projects and experiments, including antenna construction and modelling, kit building, station setup, restoration and more

I wanted to mount an amateur radio antenna on my truck that was more permanent than the magnetic mount on I already had, but I had a few specific design requirements for the project.

Home of GB3FH, 50.770MHz CTCSS 77.0Hz

Construction tips of a basic wire antenna, the half wave dipole. Inverted V dipoles and effects of inverted v on radiation pattern.

The Carolina Amateur Radio Club is a service-oriented club and has been in existence for more than 30 years

How Oscilloscope works and how oscilloscopes are done, with main components like Vertical Amplifiers and Horizontal Scanning or Sweep Circuits

Formed in 1998 with the aim of encouraging Amateur Television (ATV) activity in the North London/Lea Valley area, and specifically to establish an Amateur Television repeater in North London.

Current Solar Wind Conditions

Free to download PDF book about operating The VHF/UHF bands written in the early to mid-1990s by a team of experienced VHF/UHF DXers and equipment developers, in an effort to pass on their knowledge and stimulate further developments.

The South Milwaukee Amateur Radio Club is an ARRL general-purpose affiliated club with Hams from all interest groups

A review of the GAP Challenger DX Antenna that is not a traditional 1/4 wave vertical, but is a vertical dipole, this gives it several advantages over a standard 1/4 wave vertical, mainly the reduced number of radials, with excellent performances.

This article presents an innovative homebrew antenna design utilizing surplus ladder line as a receiving antenna for HF and MF bands. The Ladder Line Antenna (LLA) transforms standard 450-ohm ladder line into a directional, bidirectional, or omnidirectional antenna system through different termination methods. The design, which requires minimal space and height, achieves 6-10dB front-to-back ratio on 40-160m bands using a 33-foot length. This DIY wire antenna project offers an efficient, low-profile solution for amateur radio operators, featuring broadband operation without ground radials and easy installation below fence height.

Getting Started on the Magic Band is a very exaustive article about operating the six meters band. It covers several aspects of operations, techniques, tips and guidelines on getting started on the six meters band.

A multiple page article about assembling the antenna system, this section includes informations on constructing of the concrete tower base, starting from setting up correctly the foundations in relation to the antenna height.

The Ford Amateur Radio League, the Tin Lizzy Club

A video demonstrating one of the great features on the IC-7851, the ability to have two scopes on the display at the same time.

HARIG is the radio club for people in and around the Harwich area in NE Essex on the east coast of the United Kingdom.

Tim Kirby G4VXE gets a first look at the much-heralded FTdx101 from Yaesu.