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Italian contesting logging program from windows by I8VKB

Yagi-logper is a linux GPL program to model a Yagi or Log-periodic antennas with horizontal cylindrical dipoles.

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

Calculate EH Antenna, 20m 40 80m. Fotos, Original eh antenna building.

The industry standard in all antenna products

Analog circuit simulator for Windows (not a SPICE). A great tool for students, amateurs, as well as for experienced engineers. Free Demo.

Designers and manufacturers of radio Frequency antennas. HF - 3000 MHz TET Emtron HF Yagis, Antennas for Wireless applications, Marine antennas, Land mobile, Mobile antennas.

Article about homebrewing a G5RV antenna by KC6CFF

K2 logging system by WB2QAP, logs ARCI sponsored contests and others with same point system

Hy-gain HAM-IV rotator control with Arduino by OK1BIL

This article will help to unravel some of the mysteries as well as giving useful operating tips to maximize your chances of working that rare station

An email list for the discussion of the Kenwood TS-120 transceiver.

N6RK receive 4 square antenna with transformer coupled antennas and true hibrid combiner

Radio communication equipment installation recommendations

A schematic antenna for a 40-80 Morgain dipole antenna with diagram and pictures, article partially in german

World Time and Mapping software including Azimuthal Maps.

How to build the Quickie Pneumatic Antenna Launcher

Links to US local emergency service local units

A dual band wire antenna project in Italian

Welcome to the farm, where the primary crop is big towers and antennas.

Free memory management software for the Yaesu FT-991 and FT-991A models. It runs only on Windows 7, 8, 8.1, 10 both 32 and 64 bits, it also permits basic remote control features and allow backup and restore settings and memories. Documentation in mainly in French.

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

Beautiful Colorado mountain cabin with ham radio access at the foot of Mt. Princeton

50 MHz meteor scatter offers a unique opportunity for amateur radio operators to make long-distance QSOs, even when the band appears dead. Meteor scatter involves reflecting radio waves off the ionized trails left by meteors burning up in the upper atmosphere, typically around 105 km high. These trails can facilitate contacts over distances up to approximately 2,300 km. The technique is particularly effective during meteor showers, which increase the number of meteors and thus the chances of successful QSOs. However, random meteors can also be used to achieve contacts, especially on the 50 MHz band, where the longer reflection time compared to 144 MHz makes it easier to work meteor scatter. Operators should be prepared to make QSOs in short bursts, often lasting only a few seconds. The IARU Region 1 meteor scatter procedure recommends using 2.5-minute periods for telegraphy and 1-minute periods for SSB, though shorter periods can be arranged. For 50 MHz SSB, 15-second timing is often used to maximize the chances of completing a contact. The procedure involves specific timing for transmissions based on direction and requires both operators to confirm receipt of callsigns and reports to complete a QSO. Understanding the geometry of meteor scatter, including the optimal radiation angles and the concept of 'hot spots,' is crucial. These hot spots are areas where reflections are most likely to occur, influenced by the Earth's rotation and the path of the meteors. Proper antenna setup, including elevation control and beam direction, can significantly enhance the chances of successful meteor scatter QSOs.

A lightweight inverted vee antenna that can be supported by a 10 metre long fiberglass squid pole. The antenna is designed to cover 10, 15, 20, 40 and 80 m bands.

Russian radioscanning site

Presents the Aceco product line, focusing on their range of frequency counters, RF testers, and specialized bug finders. It details the capabilities of the _FC-1000_ and _FC-2000_ series as user-friendly, affordable frequency counters operating up to 3 GHz. The resource also highlights the _FC-3002_ as a portable RF finder capable of automatically tuning _ICOM CI-V_ or AOR scanners to detected signals, emphasizing its utility in secure monitoring. Furthermore, it describes the _FC-5000_ series as a wideband FM receiver that rapidly locks onto and demodulates FM signals, outputting audio through a built-in speaker, making it suitable for counter-surveillance and radio communication testing. The page provides technical specifications and operational distinctions for each product series. The content is structured to differentiate between the core functions of frequency measurement, signal tracing, and FM signal demodulation across the various models. It clarifies that these devices are not traditional scanners but offer faster signal acquisition for specific applications. The information is presented in both English and German, with a note indicating ongoing translation efforts for the German sections. The resource serves as a product catalog and technical overview for Aceco devices, distributed by WiMo Antennen und Elektronik GmbH, providing essential details for potential buyers interested in RF measurement and surveillance tools.

ACOM 1000 modification uses electric band switching, such that both 6m and 4m operation can be maintained.

Internet comunity site in Spanish

W0RW article that guide you to using beacons to determine dead bands or upcoming propagation openings.

Processing a single RTTY signal from a transceiver's 3-kHz audio, GRITTY employs _Bayesian statistics_ for superior decoding accuracy compared to traditional trial-and-error methods. This approach not only decodes 5-bit Baudot codes but also calculates the probability of error for each bit, enabling features like color-highlighting unreliable characters and smart squelching based on error probability rather than signal amplitude. This allows decoding of very weak signals while suppressing strong, undecodable interference, resulting in minimal garbage text. The program intelligently analyzes decoded text, comparing similar callsigns bit by bit and merging probabilities using the Bayes formula. This often allows GRITTY to determine the correct callsign and place it on the call stack even when all received copies are corrupt. The same methodology is applied to correct errors in exchange numbers and CQ/DE keywords, and to fix incorrect shift states. GRITTY offers an open API interface, documented in its Help file, for integration with other programs, allowing them to receive decoded data and mouse click events.

How to check for propoer connector installation by using a common multimeter to verify conductivity and resistance.

CB radios and antennas are available online at WeAreCB.com. Everything from police scanners to ham radio antennas in one convenient location.

NetTime is a simple and free software to sync your computer clock via internet. Very useful tool for FT8 FT4 operating modes.

DIY a sector antenna for de Wifi 2,4GHz ISM band.

My Version of Wes Hayward W7ZOI / Terry White K7TAU Spectrum Analyzer

An interesting home made project of an L Network Antenna Tuner Project with pictures and schematics by K7SFN

Manufacturer of small portable telegraph keys, keyer paddles, and electronic keyer products.

This homebrew six-meter linear amplifier started off life as a "junker" Alpha 76PA h.f. amplfier. Power output is 800W

Engineering Solutions for Unique Problems. Manufacturer of high Voltage, high Current, high Power Power Supply

A Working analysis of the gamma match problem that gives useful practical results in a article dated April 1969.

How to cheaply track ships using AIS and a cheap $20 software radio.

Basic information on the folded dipole antenna

RADIOING eEngineer RFI EMI information

Notes on using the Kenwood TH-D7

A microphone preamplifier schematic for hand-helds by ON6MU

Contest, Antennas, Rotating Towers, Rotors, Guywires, CoaxHardlines, Specs and more

Quick reference guides for yaesu radios

San Diego Repeater Association. We maintain oper ham repeaters throughout San Diego and Imperial County, California.

A self-contained and portable SDR Transceiver using a Softrock front end and embedded Digital Signal Processing ... No PC required!