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Personal blog dedicated to the world of ham radio. Ivan Palcic, Novalja, island Pag, Croatia

A diverse club of amateur radio operators from around Kentucky's Bullitt and Jefferson county areas.

Presents the full owner's manual for the _Drake R-4C_ communications receiver, specifically a late version edition. This resource outlines the comprehensive operational instructions, covering everything from initial setup and tuning to advanced features and controls. Hams can reference detailed diagrams and explanations for proper signal reception across various amateur bands. The manual includes critical information for alignment procedures, ensuring the receiver performs to its optimal specifications. It details the steps required for calibrating the internal circuitry, which is essential for maintaining sensitivity and selectivity over time. My experience with vintage Drake gear confirms the value of these original documents for accurate adjustments. Furthermore, the document provides insights into troubleshooting common issues and performing routine maintenance. It serves as an authoritative guide for anyone operating or servicing this classic piece of amateur radio equipment, helping to preserve its functionality for years of DXing and ragchewing.

Design, develop, test and manufacture a wide range of Amplifier products including highly linear class A Broad Band, Cell Band, Pulse, AM & FM broadcast and Military VHF

Microprocessor based interface designed receives a signal from a Morse key, processes it, and re-transmits it to the radio. A microprocessor in the circuit is pre-programmed with a proprietary algorithm which makes a number of measurements and adjustments to the less percise human generated code.

Constructing an End-Fed Half-Wave (EFHW) antenna offers a practical solution for HF operators seeking a multiband wire antenna without the need for extensive radial systems. This design typically employs a high-impedance transformer at the feed point, matching the antenna's inherent high impedance to a 50-ohm coaxial feedline. The article specifically details a 2012 approach, focusing on a transformer with a 49:1 turns ratio, which is a common configuration for EFHW antennas. The resource outlines the construction of a wire element cut for a half-wavelength on the lowest desired band, with specific coil arrangements enabling operation on harmonically related bands such as 40m, 20m, and 10m. It discusses the physical dimensions and winding details for the matching transformer, often utilizing a ferrite toroid core to achieve the necessary impedance transformation. The content provides insights into the operational principles and practical considerations for deploying such an antenna, including methods for tuning and optimizing performance across multiple amateur radio bands. While acknowledging that the presented information from 2012 may be superseded by newer insights, it serves as a foundational reference for understanding EFHW antenna theory and construction.

Official CQ World Wide DX Contest Rules.

An introduction to develpment of morse keys in radiotelegraphy history

Offer a Direct Digital VFO Kits (variable-frequency oscillator) using the Analog Devices AD9951 by WA1FFL

Home of the Arctic Amateur Radio Club

**Low SWR Podcast** was a dedicated platform for amateur radio enthusiasts, produced by Rich, **K0EB**, and his son Brady, **AC0XR**. The podcast covered a range of topics relevant to the ham radio community, including technical discussions, DXing, and radio news. Episodes were crafted to engage both seasoned operators and those new to the hobby, providing insights into the evolving landscape of amateur radio. Despite its cessation in 2014, the podcast remains a testament to the dynamic nature of ham radio, reflecting the changing interests and priorities of its creators. The podcast's archive offers a valuable snapshot of amateur radio discourse during its active years. While no new episodes have been produced since 2014, the existing content continues to serve as a resource for understanding past trends and discussions within the community. The podcast's focus on technical content and real-world applications made it a useful tool for operators seeking to enhance their knowledge and skills. Although inactive, the Low SWR Podcast's legacy persists, highlighting the enduring appeal and educational value of amateur radio media.

UT7UT ukrainian radio station

My view on the world of AMATEUR RADIO- "Rambling on" so to speak

Sixty-meter repeaters typically use a 1 MHz frequency separation between input and output, while 2-meter repeaters commonly employ a **600 kHz** split and 70-centimeter repeaters use a **5 MHz** offset. This article details the fundamental technical principles of amateur voice repeaters, explaining how they extend VHF/UHF communication range by receiving on one frequency and simultaneously retransmitting on another. It covers essential components such as receivers, transmitters, filters, and antennas, often situated on elevated locations for optimal coverage. The resource delves into the critical challenge of _desensing_—where the repeater's strong transmit signal overpowers its own receiver—and the engineering solutions employed, including antenna separation and the use of high-Q cavity filters. It also explores various control and timing systems, from basic squelch activation to more sophisticated microcontroller-based boards that manage functions like voice identification, time-out timers, and fault protection. Different access methods are discussed, including open access, toneburst, CTCSS subtone, and DTMF, each offering distinct advantages for managing repeater usage and mitigating interference. Furthermore, the article examines repeater linking, both conventional RF methods and modern internet-based solutions, highlighting how linking expands coverage and promotes activity across multiple repeaters or bands. It introduces less common repeater types such as 'parrot' repeaters, which use a single frequency and digital voice recording, and linear translators, capable of relaying multiple signals and modes simultaneously across different bands, often found in amateur satellites.

The prototype for this amplifier was originally designed for 70cm and was used on the 2004 3B9C Dx-pedition to Rodriguez Island for satellite and EME. It had a noise figure of 0.49dB with an associated gain of 20dB.

Information on staying healthy while flying

High power, UHF, L-band, S-band, C-band, microwave frequency amplifier and oscillator devices, pulsed, CW, fixed-tuned, or tunable devices in the range of 600 MHz to 2000 MHz

An universal antenna tuner interface, the Kenwood Remote LDG Tuner Interface by af6sa

MegaWave Corporation's goal is to provide services and products of the highest quality to its many customers in the areas of antenna design and development, and radiowave propagation.

Rainbowkits.com is a manufacturer of electronic kits for the hobbyist as well as for education.

RF Wattmeters - RF Power Measurement - Bird Wattmeters Telewave - Coaxial Dynamics Wattmeters - Daiwa Wattmeters

You can shorten a vertical antenna by using a loading coil. This online calculator tells you how the amout of inductance your loading coil will need to have.

Custom Designed Photo QSL Cards, Full Color stunning designs, High Quality Printing at competitive Prices. US based QSL designer and printer specialized in custom-designed ham QSL cards.

The wire antenna described in this page provides much stronger signal strength while staying within the concept of a dummy load antenna.

This project takes after the VGA-to-Scope converter by using composite video rather than VGA signals to create a display on an oscilloscope.

Since November of 1998, The Freewheelers Net has been on the air on 3.916 MHz

How fix Astron 70 model number VS-70M amp meter not working

Hall County ARES - The Hall County Amateur Radio Emergency Service has been organized to aid the public of Hall County and surrounding communities.

Review of the Heil PR-781 with a Yaesu FT-950 includes youtube movies and a nice product review

Review of the ICOM IC-7100 by M0ZZM owner of a IC 7400 and IC 7000

HM-36 Modification to make it work with an IC-7200 and the IC-7600

The Kentucky Contest Group (KCG) website, maintained by N4GN, serves as a hub for amateur radio operators interested in **radiosport** contesting within Kentucky and southern Indiana. It details the group's dedication to promoting contesting, offers links to KCG officers, membership rosters, and upcoming meetings, and provides access to an active KCG e-mail reflector and Facebook Group for member communication. The site also features a comprehensive list of N4GN's recommended ham radio web picks, covering various categories like contesting resources, DXing, VHF/UHF/Microwave, and propagation information. The KCG's map center coordinates were updated on May 16, 2015, shifting approximately 16.5 miles SSW to 37° 21' N, 85° 39' W. Despite acknowledging current inactivity and an outdated web presence, the group remains operational, exploring options for reorganization, including a potential merger with the Tennessee Contest Group (TCG), which was ultimately rejected. The site emphasizes that membership applications are considered from anyone with a genuine interest in contesting.

QRPGuys is an organization of hams that offers budget and unique ham radio kits.

Monitoring extremely weak signals in the QRSS (Very Slow Morse) mode requires specialized receiving and processing capabilities to extract information below the typical noise floor. This project provides a software solution, _QrssPiG_, designed to run on a Raspberry Pi, enabling it to function as a dedicated QRSS grabber. It interfaces with various Software Defined Radio (SDR) devices, including the popular _rtl-sdr_ dongles and _HackRF_ units, to acquire raw I/Q data streams. The software then performs the necessary signal processing to visualize and decode these faint, long-duration CW transmissions, often operating with milliwatts of power. The system leverages the computational power of the Raspberry Pi for real-time signal analysis, allowing hams to participate in QRSS experiments and monitor distant beacons. It supports different SDR hardware, offering flexibility in setup and deployment for home stations or remote monitoring sites. The project includes detailed instructions for installation and configuration, making it accessible for those familiar with Linux environments. This grabber is particularly useful for tracking propagation on the LF and HF bands where QRSS activity is common, providing a visual representation of signal presence over extended periods.

UK based CB Radio, Ham Radio, PMR Radio web forum

Effect of radials on the efficiency of antennas.

With the new name TRANSRADIO, the former TELEFUNKEN SenderSysteme AG enters into the new digital age of Broadcasting – DRM.

My blog is general info regarding HAM radio hobby and collection of my QSL cards

Receivers and transmitters by Collins , Drake , Hallicrafters , Hammarlund , National Receivers

The EU Sprint Gang hereby invites you to participate in the four European Sprint Contests.

Diamond W8010 Multiband Dipole Modifications

Build a digital AC voltmeter to measure the output range from 0 to 150VAC with reasonable accuracy

Dundalk Amateur Radio Society. Ireland Calsigns EI7DAR EI0W

World leading specialist in manufacturing, providing design services for small scale wind turbine systems and parts (<30kW)

It is very compact, low noise and directive with an impressive 20 to 25 dB front to back

Drake TR-7 A.M. Transmit Filter Modification

This Guide helps you to build the 1:2 BalUn 600 Watts DIY kit step by step. If a delta-loop or quad-loop antenna is powered with a coax cable from the transceiver it is necessary to use a 1:2 BalUn. This 1:2 BalUn uses a symmetrical 1:2 impedance transformer.

DXLook is a free, web-based propagation platform that delivers comprehensive, real-time insight into HF and VHF conditions directly from any modern browser. It aggregates live spots from PSK Reporter, WSPRnet, RBN, and DX Cluster, complemented by NOAA space-weather metrics such as SFI, K/A indices, and geomagnetic alerts. Integrated VOACAP predictions allow practical "theory versus reality" comparisons, while the interactive world map with filters, gray line, and grid overlays enhances situational awareness. With no installation or maintenance required, DXLook provides a convenient, accurate, and accessible solution for everyday operating and propagation analysis.

Local APRS info & Tracking