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Ham radio links and more

Audio setup at N2RIT built around the Yaesu FT-950 abd the Heil Sound PR-781 an ultraflex PRO EX3200

The Peekskill / Cortlandt Amateur Radio Association, Inc. (PCARA) is a Volunteer Non-Profit Community Service Organization Serving the Greater Peekskill / Cortlandt Area of Westchester and Putnam Counties in New York State. PCARA operates three voice repeaters in the Northern Westchester / Southern Putnam County region of New York State.

RSN International DX Group, free and relatively big club for all DX'ers!

A nice tutorial and the basics of the software defined radio, SDR, and links of software defined radios to JTRS, and general SDR receiver technology.

Demonstrates the design and functionality of _uLog_, a Windows-based logging application for amateur radio operators. The resource details its core purpose as an easy-to-use logbook, emphasizing its streamlined interface that provides only the basic fields necessary for efficient QSO entry. It positions _uLog_ as a practical alternative to more complex logging software, catering to operators who prefer simplicity and speed in their logging workflow without an abundance of advanced features. The application's utility is highlighted by its focus on fundamental logging tasks, distinguishing it from comprehensive contest loggers or DX cluster clients. While not explicitly comparing it to other specific software, the description implies its niche for everyday logging rather than specialized operating events. Its design philosophy prioritizes quick data input, making it suitable for casual operating or for those who desire a minimalist approach to maintaining their station log.

Introduction to WSPR beacons. Article describe WSPR2 and WSPR15 beaconing mode and include a frequency reference table for both WSPR modes

Ham radio Dxpedition

Yaesu FT-817 noise blanker improvement

Ham radio activities, from satellite operations, eme communications, dxing and contesting, qsling and direction findings, are just some of ham radio exciting activities

Amateur radio kits. Makers of the WinKeyer, their goal is to keep homebrewing and kit building alive.

DIY beacon for six meters band by K9MU

Dutch Packet Radio link site..

The Reverse Beacon Network (RBN) graph presents a dynamic visualization of amateur radio spots, specifically tracking CW, BPSK, and RTTY signals over the last 15 minutes. Users can filter these real-time spots by DX continent, spotter continent, and individual frequency bands, including **160m through 70cm**. The interface also offers a bandwidth reduction option, which is particularly useful for operators with limited internet connectivity. This resource provides a unique perspective on propagation conditions and station performance by aggregating data from various _Reverse Beacon Network_ nodes. It automatically refreshes every 10 seconds, ensuring that the displayed information is current and relevant for active DXers and contesters. The graph's Y-axis represents time, with each spot indicating activity within a one-minute interval. Beyond the primary RBN graph, the platform also features dedicated maps for both DXCluster and RBN data, including azimuthal projections. An additional FT8 graph is available, though noted as being under construction, indicating ongoing development to expand its utility for digital mode enthusiasts. The system was developed by HA8TKS, with the initial concept attributed to CT1BOH.

Getting started on RTTY contesting. A PDF by ED Muns, presented at CTU conterst university, about amateur radio RTTY Contesting

MS Excel document that allows you to plot SWR, resistance, reactance, impedance magnitude and angle and more from a variety of sources

The page provides detailed instructions on how to build a 60 meter End Fed Half Wave Antenna Tuner, with large pictures and diagrams. It is aimed at amateur radio operators looking to construct their own antennas for the 60 meter band.

Software defined radio products. Maker of AFEDRI SDR a direct sampling Software Defined Receiver by 4Z5LV

A Low Power Indoor Portable HF Antenna by N5ESE

Memory recorders, Power meters, testers and multimeters, noise testers, signal generators

Another general tutorial on BPL

The _Sci.Electronics FAQ: Repair: RFI/EMI Info_ document, authored by Daniel 9V1ZV, provides a detailed analysis of computer-generated RFI/EMI, focusing on its impact on radio reception. It identifies common RFI sources such as CPU clock rates (e.g., 4.77 MHz to 80 MHz), video card oscillators (e.g., 14.316 MHz), and even keyboard microprocessors, all of which generate square-wave harmonics across HF and L-VHF regions. The resource outlines a systematic procedure for pinpointing RFI origins, including disconnecting peripherals and using a portable AM/SW receiver with a ferrite rod antenna to localize strong interference sources. The document categorizes RFI mitigation into shielding, filtering, and design problems, offering practical solutions for each. It recommends applying conductive sprays like _EMI-LAC_ or _EMV-LACK_ to plastic casings of radios, monitors, and CPUs to create effective Faraday cages, emphasizing proper grounding and avoiding short circuits. For filtering, the guide suggests using line filters, ferrite beads, and toroids on power and data lines, and small value capacitors (e.g., 0.01 uF for serial/parallel, 100 pF for video) to shunt RFI to ground. It also discusses the use of bandpass, high-pass, low-pass, and notch filters on the receiver front-end or antenna feed to combat specific in-band noise.

An High voltage power supply design by F1FRV

Rules of CQ World Wide RTTY Contest. The CQ World Wide RTTY DX Contest take place last full week-end of September, inviting amateur radio operators globally to connect across various CQ zones and countries. Participants will operate on five designated bands: 3.5, 7, 14, 21, and 28 MHz, exchanging RST reports and zone numbers. Scoring is based on QSO points multiplied by zone, country, and QTH multipliers. The contest encourages innovation in operating strategies while adhering to established rules to ensure fair competition among entrants.

Initial set up of Broadband Hamnet on a Raspberry Pi.

Unfilter LF output from the TH215/415 kenwood portable radio

A homemade GPS for TM-D710 using a Telit Jupiter JN3 GPS unit

KD5FX, 20 through 6 meters, QRP to full legal power, lightweight, easy to carry

Cocos-Keeling Islands, Christmas Island Online Log

The ZL1BPU Rotator Controller has been designed as an add-on unit for the popular Kenpro KR-400 and Yaesu G-400 rotators. The controller consists of a small circuit board which fits inside the rotator control box

AD7DB discussion about HF wire antennas

Tape measurement yagi. The longest part is 530 mm, easy fit to your backpack. Very easy and fast deploy. Great for SOTA and portable operation. Can be used in horizontal or vertical polarization. Based on DK7ZB design

Operates fast-scan FM-television in the 1.3, 2.3 and 10.3 GHz bands

A 2x3-foot laminated world map product is detailed, offering customization for amateur radio operators. Each map features two distinct views: one centered on the operator's specific station location and another precisely centered on its _antipode_. Countries are clearly labeled, complemented by a tabular listing of all countries. The map integrates a standard latitude/longitude grid alongside concentric circles that delineate distance increments radiating outward from the operator's QTH. Personalization includes the operator's name, callsign, and location printed directly on the map. This custom mapping service provides a unique visual aid for DXing and propagation analysis, allowing operators to quickly ascertain beam headings and distances from their station. The dual-view presentation, particularly the antipodal centering, offers a practical reference for understanding long-path propagation and identifying potential DX opportunities. The inclusion of distance circles and personalized station data makes it a tailored tool for daily operating and contest planning, distinct from generic world maps.

A look behind the scenes, learn how the ARRL laboratory evaluates new products, and what all those numbers mean to you by WA1SVF

Marshall G. Emm, N1FN, meticulously examines iambic keying, dissecting its historical introduction in the late 1950s with transistorized electronic keyers and its purported advantages. The resource defines keying systems, electronic keyers, and various paddle types, including single-lever and dual-lever paddles, clarifying the distinction between iambic keyers and the iambic sending technique itself. It details the two main types of squeeze keying: true squeeze for alternating dot-dash strings and character insertion for specific elements within a character. N1FN critically evaluates the actual efficiency gains of iambic keying, referencing Chuck Adams, K7QO's, keystroke analysis. While a straight key to bug transition yields a 34.1% reduction and a bug to non-iambic keyer offers 16.1%, iambic keying provides only an 11% theoretical improvement. However, considering typical QSO text and Morse code's inherent optimization for common letters, the practical efficiency gain is estimated at a modest 4-6%. The article also highlights how iambic keying's reliance on precise timing gates can impose a speed limit, making it less effective above 40 WPM, where many operators revert to non-iambic methods or single-lever paddles.

A simple direct conversion receiver for 80m. The receiver covers 3.51 MHz - 3.60 MHz and 3.64MHz - 3.71 MHZ - CW and Phone portions by M0DGQ

Contesting Norway, forums on contesting from scandinavia.

A free PDF from NASA about cubesat. Basic Concepts and Processes for First-Time CubeSat Developers. A great introduction document dedicated to Cubseat developers.

RadioReference.com page dedicated to the Drake TR-7 HF transceiver

NFDXA On-Line Eritrea DXpedition Log

How to calculate range for a VHF antenna with a simple formula and how to increase VHF coverage.

With the purpose to let people know about the Castles built on the italian territory and the value which the historical architectural estates hold. Diploma Castelli Italiani by IQ1BP.

River City Amateur Radio Communications Society

Trio Datacom, Dolectek and Yaesu Vertex Standard cb and ham radio dealer in new zealand

Linux for shortwave and amateur radio monitoring. Supports popular SDR hardware and online streaming from KiwiSDR, WebSDR, and Spyserver sites. Articles about using Linux with your SDR devices.Skywave Linux, an innovative operating system, leverages cutting-edge technology for seamless access to radio signals globally. Ideal for regions with limited internet access, it effortlessly connects to a network of SDR servers, offering high-performance SDR operation without the need for extensive hardware. With pre-installed and configured SDR software, Skywave Linux simplifies signal discovery and operation for all users.

This is a QST Article published in January 1982 by W1FB D. Demaw and HH Beverage and is a complete review of the original article published in 1922, which updates and reivew the beverage antenna theory and developlment, explaining the antenna design of transformers and gives accurate reports on antenna general performance.

VQSpot is a simple utility program developed for sending DX-Spots automatically when QSO are logged into VQLog

The Central Texas DX & Contest Club (CTDXCC) is a group of Amateur Radio operators in the central Texas

dogparkSDR is a native Macintosh visual radio display and interactive control software for any Flex Radio Systems