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Build and run your own ADS-B receiver for 100 USD with a Raspberry Pi

This R.F. current meter was developed to assist in measuring line currents in balance feed lines as used in the All Band HF Antenna.

The South Alabama Radio Club is located in Covington County, Alabama in grid square EM61

How can the current "flowing" out of the top of a mobile loading coil be greater than the current "flowing" into the bottom of the coil?

Mobilinkd Bluetooth APRS TNC. With your radio, your Android phone and this TNC, you have everything you need to get started with APRS.

Designed to handle audio signal interfacing as well as transmit/receive switching Reviewed by Steve Ford, WB8IM

WinXXDataConverter is a Windows GUI application that will convert files between the various formats used by Win92, Win93, Win95, and Win96.

Gnerate morse code at various speeds and with lots of different types of content, everything from individual letters up to a full QSO.

Batterieries for ham radio handheld radios and more

Manual of the BD-35 Dual Band VHF UHF RF power amplifier by Mirage Amp

Radio Interferences, QRN, or noise, information by W8JI

Dedicated to serving for all rotator parts needs. Stock and provide rotor parts for antenna rotators from companies such as Alliance, C.A.T.S., CDE, Channel Master, and Hy-Gain, both young and old.

The Rochester VHF Group, the oldest VHF-Oriented club in the World

The CSV19 is an homemade antenna launcher project. In this article you can find pictures, drawing, and material list

The TransWorld Antennas TW4040 The Adventurer Monobander™ is a portable HF antenna designed for rapid deployment in field operations, including **SOTA** and **POTA** activations. This manual details the antenna's assembly, tuning procedures, and operational guidelines for optimal performance on the 40-meter band. It outlines the specific components, such as the telescoping whip and base unit, required for proper setup. Instructions cover mast erection, radial wire deployment, and impedance matching to achieve a low **VSWR** across the designated frequency segment. The document also provides guidance on antenna orientation and environmental considerations for portable use. It specifies the antenna's power handling capabilities and physical dimensions when fully deployed and collapsed for transport.

Filters for the commercial 2 way market, MATV, FM broadcast, laboratory, marine industry, amateur radio, scanner and short wave. Antenna for amateur radio bands

Antique radio collection from brazil, philips , philco, telefunken, blaupunkt, saba, mende, rca, ekco, pilot, general electric, bush and more

Operating a ham station often involves encountering radio frequency interference (RFI), RF feedback, or RF burns, which are frequently misattributed to poor equipment grounding. This resource meticulously dissects these assumptions, asserting that RF grounds on the operating desk often merely mask more significant system flaws. It identifies five primary causes for RF problems, including antenna system design flaws, proximity of the antenna to the operating position, DC power supply ground loops, equipment design defects, and poorly installed connectors or defective cables. The content emphasizes that issues like "hot cabinets" or changes in SWR when connecting a ground indicate substantial RF flowing over wiring or cabinets, a phenomenon known as common-mode current. The article provides detailed explanations of common-mode current generation, particularly from single-wire fed antennas like longwires, random wires, and OCF dipoles, which inherently present high levels of RF in the shack. It also illustrates how vertical antennas, lacking a perfect ground system, can excite feed lines with significant common-mode current. Through simulations, the author demonstrates how a dipole without a proper _balun_ can cause RF problems at the operating desk, showing current patterns and voltage distributions on feed line shields. The discussion extends to the proper application of _RF isolators_ and _ferrite beads_, clarifying their role in modifying common-mode impedance on cable shields and cautioning against their use as a band-aid for fundamental system defects. The resource advocates for correcting the actual source of RF problems, such as antenna system issues or poor connector mounting, rather than relying on internal shack grounding or isolators. It highlights that properly functioning two-conductor feed lines, like coaxial or open-wire lines, should result in minimal RF levels at the operating position, even without a desk RF ground. The author shares personal experience, noting that his stations since the late 1970s have operated without RF grounds at the desks, relying instead on proper antenna system design and feed line integrity.

qrpTracker is a satellite tracking program that works on the popular and easy-to-program Arduino platform qrpTracker is meant for amateur satellite enthusiasts and computing hobbyists

A multiband vertical antenna for HF bands with elevated ground radials slant down at 45 degrees and acting also as guy wires.

This version of the broadband hexbeam is based on the work of Hunt G3TXQ, HB9MCZ, and Shoemaker K4KIO. EZNEC model is based on a wider element spacing than the version published in QST by K4KIO

Comparison of all the oscilloscopes available for hobbyists, digital oscilloscopes that you can get for under $500, or oscilloscopes that you can build yourself.

Explains the fundamental principles of Software Defined Radio (SDR) and Digital Signal Processing (DSP) within the amateur radio context, serving as an initial entry point for hams interested in these technologies. It covers the architectural shift from traditional analog hardware to software-centric radio systems, detailing how digital signal processing algorithms are applied to modulate, demodulate, and filter radio signals. The resource compiles a list of external links to _white papers_ and project pages, offering further technical depth. This page provides a foundational understanding of SDR/DSP, enabling operators to grasp concepts like direct sampling and quadrature mixing. It references various projects and discussions, allowing users to explore practical implementations and theoretical underpinnings. The curated links direct users to resources that might cover specific SDR hardware platforms or software applications, facilitating deeper research into the subject.

Changing band selector to a Kenwood TL-922 power amplifier by IW1PUR in italian

The Radio Reference Database for United States

Personal (b)log by a SWL in north Italy

Kenwood schematics diagrams in high resolution format, includes Kenwood TS-830S , TS-820S and TS-520S

NewLogOSH is a logging application for amateur radio operators, featuring integrated support for various digital modes including FT4, FT8, RTTY, and PSK. The software incorporates DXCluster connectivity and radio interfacing capabilities, allowing for seamless operation with transceivers. Its database is built within the SQLite environment, providing a robust and portable data storage solution for logging QSOs and managing station information. The program's architecture focuses on practical functionality for daily amateur radio operations. Operators can utilize NewLogOSH for contest logging, general DXing, and managing their station's contact history. The inclusion of FT4 and FT8 modes reflects current trends in digital communication, while RTTY and PSK support caters to established digital protocols. The DXCluster integration provides real-time spot information, aiding in DX hunting and propagation analysis. Its SQLite backend ensures data integrity and ease of backup, making it a reliable tool for maintaining comprehensive station logs.

Heathkit SB220 refurbishing by PA5CA

Coil winding on 4 inch PVC tubing with home-made tooling.

A 600W 1.8 MHz to 54 MHz power linear amplifier made using rugged MRF300 transistors featuring output power between 580W and 750W depending on band, power supply: 48V, 18A typical, 20A max

M0CVO Antennas, amateur radio antennas for fixed station or portable operations, HF/6m all are catered for. The antennas produced by us are all manufactured by Nigel Booth, M0CVO

T2FD is a 600-900 ohms folded dipole, terminated with resistor. Feed impedance is coupled with 50/600 ohms voltage balun. It is a wide band antenna with rather low SWR over the full designed frequency range: antenna tuner is seldom needed.

Bohannon Battery Distributors, for All your Battery needs, since 1987

ICQ Podcast The home of the Premier Amateur Radio Podcast, podcasts, forum and Amateur Radio News and views.

Serving Columbia and Greene Counties of New York State

This site is dedicated to design and analysis of micro- and millimeter wave filters from 0.5 to above 100 GHz.

President Karami Radio Society. Amateur Radio Club Station OD5RAK, Tripoli - Lebanon

How to understand resistor colour codes

A homemade band pass filter for the 30 meter band based on the original VE7BPO design

A sharewave windows logging program for the ARRL 10 meter contest by N3FJP

An interesting article on how build an optimal sounding communications loudspeaker capable to optimize sound reproduction at the frequency range from 150 Hz to 3 kHz.

Solar panels manufacturer based in spain

Manufacturer of advanced electronic systems to measure such weather data as: wind speed, wind direction, wind chill, pressure, humidity, rainfall, and dew point.

A Chaotic Collection of Keys, Paddles, and Bugs

Site officiel du world lighthouse on the air award - official web site for wlota award

Modification to solve key clicks on FT 1000 MP

Solar Panels Grid Tie Systems, Kits, Fountains, Chargers and more

Guidelines for optimal speaker placement inside our ham radio shacks

A very active repeater system in NYC streaming live 24/7 on thier website & on shoutcast under the listing WB2HWW & also can be heard world wide on 10 meters 29.660 with links on Echolink & IRLP