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DX Cluster web interface offer a light interface with automatic spots refresh

This video shows one way to use a scope and function generator to measure the length of a piece of coax transmission line as well as estimate its impedance

Heathkit Amateur Radio Repair, parts, and manuals. Amateur radio equipment sales and service.

Understanding Common Mode and Differential Mode Currents on Transmission Lines by K9YC

Presents a Brazilian online portal dedicated to **amateur radio**, **CB radio**, and shortwave listening (SWL) communities. The platform facilitates free classified advertisements for radio equipment, including HF, VHF, and UHF transceivers, antennas, and accessories. It also aggregates a substantial collection of technical articles from Brazilian amateur radio operators (e.g., PY2DJW, PY1LJ, PY1LL/4LC), covering topics such as CW training with RufzXP, balun importance, and radio wave characteristics. Furthermore, the resource provides extensive links to Brazilian ham radio sites, clubs, international organizations, and official ANATEL (Brazilian National Telecommunications Agency) documents regarding licensing, equipment homologation, and regulations. The portal features sections for user evaluations of transactions, a "Top Ten" list of most visited pages, and a calendar of past and upcoming ham radio events across Brazil, including "Feirinhas" (local swap meets) and "Encontros de Radioamadores" (hamfests). It also includes a directory of ham radio related businesses and services in Brazil, such as antenna manufacturers (Diex), QSL card printers (Arte Final), and repair technicians (PY2MOK). The site also offers propagation maps, DX cluster links (e.g., DX-SUMMIT), and satellite tracking tools, making it a central hub for Brazilian radio amateurs seeking to buy, sell, learn, or connect with the community.

A Massachusetts Non-Profit 501-C(3) corporation of amateur radio operators chartered in 1978 covering the Connecticut River Valley in Western Massachusetts and Northern Connecticut.

Negative feedback is often referred to as shunt feedback in conjunction with emitter degeneration.

NG3K DXCC Entity tables by prefix by ng3k

KARSFEST, held at the Will County Fairgrounds. Sponsored by the Kankakee Area Radio Society. Large and well attended hamfest and computer show!

Transmission Line equations for Windows. Written in Visual C++. This program provides the most comprehensive analysis of a transmission line by w9dmk

Premier company that offers advanced products and services to protect today's structures from lightning

An efficient monoband end-fed half wave for 10m, 20m or any other HF band

Free windows world map application display current time, sunrise and sunset, greyline map, dx stations, requires windows 7 or higher. The program includes three resized Natural Earth maps which have been resized to 4k or slightly less. By Simon Brown G4ELI better known as the inventor of Ham Radio Deluxe.

An homebrew project for a 3 element coil-loaded Yagi beam antenna for 40 Meter band

The 80m TX described here is the well known ON7YD ATX-80 and timer, combined and re-engineered to fit a readily available enclosure by G3ZOI

Voltage baluns and choke (or current) baluns.

The purpose of this article is to describe in detail the Morse code keys made by the Brown Brothers Machine Company (BBMC), to aid the serious key collector in identifying each model made by this fine company.

With this tool it is possible to create QSO maps overlay on Google maps there each QSO get a line from the home location to each DX location. An EDI logbook file is used as input. The creation will only use complete locator in the 6 characters format.

Design and build an 6 m dipole antenna from aluminum, tubing, that resembles the active element of a yagi beam antenna.

Located in the centre of the UK with good grade aluminium,

Some sound samples of received signals mainly on VHF-band

Examines the Icom IC-2100H 2-meter mobile transceiver, detailing its operational characteristics and user experience. The review highlights the clear, easy-to-read display with internal labels, the button-filled microphone's functionality, and the rig's physical construction, including its weighty heat-sink and lack of a cooling fan. It also discusses memory programming, the unique amber-to-green backlight color options, and the radio's performance against _intermodulation_ in urban environments, noting it performs "pretty darn good" compared to other rigs. The analysis delves into a significant low-voltage cutoff problem, where the microphone ceases to function below approximately **12.6 VDC**, rendering the radio receive-only or causing it to stick in transmit. The author describes testing the voltage cutoff, observing it fluctuate from _12.38 VDC_ to 12.69 VDC. An update from Icom involved a "factory update" to the CPU's control code, which is strongly recommended for early-serial number units to prevent operational failure in low-power emergency scenarios.

Modifications for motorola and ericsson radio repeater

A 5 elements homemade DK7ZB yagi antenna for 4 meters band based on a 50MHz TONNA

Fast Scan Amateur Television in Southern California, Nevada, Arizona, New Mexico, Indiana and soon in Illinois.

Amateur Radio HF Cubical Quad and Delta Loop antennas manufacturer based in Spain

Activating a county for ham radio can be dangerous to your health!

Spanish web site

The essentials of the parabolic reflector or dish antenna and its theory and design for high performance applications such as satellite transmission and reception as well as microwave links.

Mountain Thunder CB Radio Group is a group of CB SSB operators that started in the Pacific Northwest, Washington State.

5-element antenna, with which G0JJL has worked lots of EU crossband, and won the RSGB Christmas Cumulatives 70MHz section twice in a row.

The European PSK Club, or EPC for short, is an informal club of amateur radio operators dedicated to maintaining high levels of amateur radio communications on PSK modes. Its purpose is to promote activity and good operating practice on the PSK modes on all amateur bands

Amateur radio good operating practices by KG9OM

HAM-IV antenna rotor repari and restore

The largest gathering of shortwave listeners (about 200) in North America, near Philadelphia in March.

The Yaesu FT-1000MP Mark-V, introduced at Dayton 2000 Hamvention, features a higher RF power of **200 W PEP** and a Class-A amplification SSB mode at 75 W. Key enhancements include an _Interlocked Digital/Analog Bandwidth Tracking system (IDBT)_, a Variable Front-End Filter (VRF) preselector, and improved ergonomics, notably a multi-function shuttle jog dial. This model, a successor to the 1996 FT-1000 and FT-1000MP, was designed to compete with high-end transceivers, despite its retail price of $4200 initially. The transceiver's physical dimensions are 406 x 135 x 348 mm (16 x 5.3 x 13.7 inches) with a weight of 14 kg (31 lbs), making it substantial. Its rear panel offers over 20 connections, including power, external DSP speaker, BAND DATA I/O, ALC, and multiple interface jacks for DVS-2, Packet, and RTTY. The unit also provides two keyer inputs, a DB9M serial interface for CAT, and two PL female antenna connectors, plus additional receive antenna jacks. Despite its advanced internal architecture, including two independent receivers with their own IF filters and AGC loops, the display technology, utilizing fluorescent discharge rather than LCD, contributes to an older aesthetic. The control panel is extensive, featuring 92 knobs and buttons, alongside numerous LED indicators for various modes and functions.

Yaesu FT 847 CAT cable

Radio Amateurs of Ankara, Turkey. English, Turkish, homepages of HAM's.

Antenna designs that K5TR have collected from various sources.

Digital amateur tv and mobile transmitting around Friedrichshafen and Lake Konstanz to be seen in Hall A. Heinz DC6MR is presenting the news, novelties and technical aspects of DATV.

Demonstrates the adaptation and construction of a 7-element DK7ZB Yagi antenna for the 4-meter band (70 MHz), utilizing components from a defunct 2-meter CUE DEE Yagi. The resource details the modifications made to the original DK7ZB design to fit the shorter CUE DEE boom length, specifically adjusting element lengths for 6mm rod elements while reusing existing mounting holes for the reflector and last director. It provides precise element lengths for the reflector, dipole (12mm aluminum tube), and five directors, along with a note on cutting elements for transport. The article includes a 4NEC2 simulation file for performance analysis and an SWR plot, confirming the antenna's electrical characteristics. It also specifies the calculation for the quarter-wavelength matching cable using SAT752F coaxial cable, resulting in a 909mm length. Practical application is shown with the finished antenna in operation at JO20XC, listing several activated Maidenhead squares such as JO56PA and JP40KS, validating its effectiveness for portable 70 MHz operations.

A Home made QRP tuner for 10-40 meters

Manufacturer of custom belt buckles,coffee mugs,t-shirts,sweat shirts,maine gifts,name tags,call tags and awards for police, fire, sheriff, ham radio and amateur radio clubs

W5AC is the Texas A&M University Amateur or "Ham" Radio Club. This club, founded in 1912, is one of the oldest university radio clubs in existence.

Analyzing a decade of contest operations and QSLing from March 1993 to March 2003, K5ZD presents data on QSO totals by band and mode, QSL error rates, and DXCC progress. The article details the author's methodology of only answering incoming QSLs, which allowed for a study of call copying error rates, found to be between 0.8% and 1.7%. These error rates correlate with typical contest log checking reports (UBN/LCR). The data also tracks the percentage of QSOs confirmed by QSL cards annually, averaging 12.1% over the ten-year period, with a steady rate of 14-15% in earlier years. Specific statistics include a total of 215,653 QSOs logged, with 26,184 QSLs received. The article identifies the top 33 countries for incoming QSLs, accounting for over 87% of the total, with Japan, Germany, Spain, and Belgium being prominent. It also touches upon the potential of ARRL's Logbook of the World (LoTW) for instant confirmations, while noting potential error rate implications. The author's station, initially a barefoot setup with a Hygain multi-band vertical, evolved into a fully operational contest station by October 1993, utilizing DX4WIN for logging.

This PDF document details the construction of a **70 MHz** Big Wheel antenna, a horizontally polarized omnidirectional array. The design utilizes three full-wave loops, each approximately **2160 mm** in diameter, arranged in a triangular configuration. The resource provides mechanical dimensions for the antenna elements and a comprehensive bill of materials, specifying component quantities and types, such as M8 stainless steel bolts, 15x15x1.5 mm square aluminum tubing for spacers, and 8 mm aluminum rod for the arcs. The central hub is constructed from two 160x160x8 mm aluminum plates, with four 40 mm long polyamide insulators supporting the radiating elements. The feed system incorporates a 50 mm diameter aluminum pipe for mounting and a matching stub constructed from a 120x20x2 mm aluminum sheet, connected via M8x10 mm bolts. The resource includes a diagram illustrating the mechanical dimensions and assembly points, including the N-connector fixing point and the center conductor attachment. The project was published on May 25, 2011, by Peter OE5MPL and Rudi OE5VRL. DXZone Focus: PDF | 70 MHz Big Wheel | Mechanical Dimensions | **2160 mm** loop diameter

About the Icelandic Alfa Tango members,DX,Iceland and all what has to do with the hobby.

ATV 432 MHz AM transmitter schematic

Club activities, news and newsletter Ham Chatter Online features a member each month. Field Day pictures, etc. Home of VOA transmitter sites. Club calls, W4AMC & W1VOA Greenville, NC

This tutorial will show you how to connect a Morse key to the Raspberry Pi GPIO pins, and how to write code to play tones when you hold the key down. You will also decode the Morse that you're keying so that it comes up on the screen.