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

Quick reference guides for yaesu radios

Mediumwave, shortwave, and amateur bands QSL cards collection

Providing quality full color QSL cards for Ham Radio operators.

This article describes a project of asymmetrical hatted vertical dipole, a portable antenna that can be used for field day operations, sota, campings or even for fixed installations. This is a freestanding 20-10m antenna that is really easy to build, easy to tune and relatively easy to carry.

Telescopic antenna towers, fixed antenna towers, stacked and sigle section antenna towers, trailer towers, cargo trailers accessories

A homebrew dummy load is usually a combination of several parallel carbon resistors, in order to be able a final resistance of 50 Ohms.

FM dx logs, MW carrier offset monitoring, lists of RDS codes in use in the UK, London pirate bandscan and much more from a London QTH.

Audio and waterfall images of some sounds found on the RF spectrum

The Clearwater Amateur Radio Society is an active amateur radio club based in Pinellas County Florida.

Generates dial tones using the Soundcard. A neat tool for sending out short sequences of DTMF tones.

QRP Station in a Bag is a complete QRP station in an old laptop PC carrying case (photo). It is a true "Work in Progress" in that wd8rif is constantly changing the contents of the bag as learn what works and what doesn't.

Examines various facets of online casino gaming, focusing on security, game selection, and payment solutions. It details the extensive gaming libraries offered by online casinos, which often feature over **4,500 games** from more than _75 top software providers_, including slots, live dealer games, and table games. The resource also covers stringent security standards, such as 256-bit SSL encryption and dual licensing from authorities like the _Malta Gaming Authority_, ensuring player fund segregation and data protection. Furthermore, the content explores diverse financial solutions, including traditional methods like Visa/Mastercard and modern options like Skrill, Neteller, and cryptocurrencies such as Bitcoin, with withdrawal times ranging from **0-6 hours** for e-wallets. It highlights mobile gaming experiences optimized for various devices using HTML5 technology, offering over 4,000 mobile-optimized games. The resource also delves into VIP rewards programs, loyalty benefits, and customer support channels, emphasizing quick response times.

The 9A3MR contest QTH rental provides a fully equipped amateur radio station for DXpeditions or radio holidays on Murter Island, Croatia. The station features a Drake TR7 transceiver and a 16-meter tower with a rotator, suitable for various HF operations. Accommodations include a four-room apartment and a studio apartment, both within 200 meters of the beach, offering amenities like parking and a barbeque area. This QTH is located in Jezera, a fishing village with local stores and restaurants within a five-minute walk. While Murter Island itself does not qualify for IOTA due to a bridge connection, the Kornati Islands National Park (IOTA EU-170) is only 10 nautical miles away, with daily tourist tours available. The Krka National Park is also accessible by car, approximately 25 km distant, providing additional recreational opportunities.

PTT and soundcard interface schematic by ON6MU

A well documented article about construction and analysis of a horizontally polarized halo antenna for 6 meters band by Dr. Carol F. Milazzo, KP4MD

Ham Radio repair of all major brands and models, located in Carrollton, Texas, which is just north of Dallas, and have been serving the Amateur Radio community for over 20 years.

RTL-SDR is a very cheap software defined radio that uses a DVB-T TV tuner dongle based on the RTL2832U chipset. This is a blog about rtl-sdr, software defined radio and their developments and applications.

Although a magnetic loop antenna(aka small loop antenna) is very compact, its efficiency is close to a half-wavelength dipole if carefully built.

IC820H or other Icom Radios Soundcard interface for VHF EME use by DF9CY

The Smith Chart was originally created many years ago as an RF engineering aid by Phillip Smith of RCA.These pages includes extesnive documentation on smith carts.

QSL Cards from ALL 338 DXCC Entities, deleted countries QSL Cards, other interesting cards

Need to interface both a TNC and the computer soundcard? This is a ICOM 756PRO ACC1 audio/keying/FSK interface by WA0SXV

North Carolina ARRL Section Information

The club was founded in 1981 by 17 Charlotte-area hams interested in DXing & contests

Accurately determining an antenna's feedpoint impedance is crucial for optimal performance, especially when experimenting with new designs or making adjustments. While SWR meters provide basic information, a full complex impedance measurement reveals the resistive and reactive components, which are essential for proper matching. Modern antenna analyzers, like the _Palstar ZM30_ or MFJ259B, simplify this task, but measurements taken through a transmission line require careful interpretation due to impedance transformation. This resource details a calibration method to precisely account for the effects of the feedline. It explains how a transmission line can significantly alter the measured impedance, illustrating this phenomenon with a Smith Chart example where an 80m antenna's [22 + j6] Ohms feedpoint impedance transforms to [82 + j45] Ohms after a 10m line. The guide demonstrates using a transmission line calculator applet, such as the one by W9CF, to reverse this transformation. It outlines the process of calibrating a specific length of RG174 coax, showing how an initial 26ft estimate was refined to **25.85ft** to accurately predict a known 22 Ohm load, significantly improving accuracy over uncalibrated results.

Collection of telegraph keys homebrew antenna projects links to radio software

BCL group in central america, caribes, about utilities, pirates and clandestins. In spanish

SignalPoint, Caribbean Contesting Consortium. Curacao. CCC's contesting QTH is the former home of PJ9JT, John Thompson, W1BIH. This historic site has been the home of many contest wins since 1971.

The Resonant Feedline Dipole (RFD) HF antenna design utilizes a single piece of coaxial cable and a stranded wire section, forming a 1/4-wavelength radiator. This configuration, based on a 1997 ARRL Handbook design (page 20.17), functions by RF traveling on the inside of the coax shield and returning on the outside, creating the second half of the dipole. A choke wound into the feedline prevents RF current from flowing back down the feedline. Construction details include using RG-58a/u coax for a 75m version, with a 1/4-wavelength section of stranded wire soldered to the center conductor. The document provides choke dimensions for RG-213, RG-8, and RG-58 coax across 3.5 MHz to 28 MHz, specifying cable length and number of turns. Dipole dimensions are also tabulated for frequencies from 3.6 MHz to 28.4 MHz, listing overall length and individual leg lengths. Field tests included deployment near Bryson City at 5 feet off the ground and as a sloper during WCARS Field Day in Asheville, yielding successful local and regional contacts.

Establishing a robust, interconnected communication infrastructure across challenging terrain, the Island Trunk System (ITS) provides a network of open amateur radio repeaters for general and emergency communications throughout Vancouver Island, surrounding waters, and parts of the lower mainland on the West Coast of British Columbia, Canada. This system, largely off-grid, relies on solar power and batteries, necessitating careful operation, especially during night hours and low solar charging seasons, to preserve its energy resources. Maintaining the ITS involves significant effort from many hams, who appreciate adherence to regulations, including proper station identification. The system hosts a weekly social net every Monday evening at 8 PM, welcoming all participants, and also supports a Vancouver Island Region Emergency Radio Net each Wednesday at 19:15. Experimental projects like the Newcastle Ridge webcams, linked via 5.8 GHz broadband backhaul over 206 km to Nanaimo and Comox, demonstrate the innovative spirit within the ITS community. A new VHF repeater, operating on 146.880 MHz with a 141.3 Hz PL tone, was installed in Tofino, expanding system coverage.

One of several Colombian broadcasting networks heard on AM and FM and worldwide on 5076 kHz in the 60 meter band.

The _Egyptian Amateurs Radio Association (E-ARA)_ provides a directory of its members, detailing callsigns such as SU1AL and SU1ER, along with their full names and QSL routing instructions. Each entry typically includes a postal box or street address in cities like Giza, Cairo, and Port Said, facilitating direct QSL card exchange. Specific entries indicate QSL via home call for operators like SU1BH (A71BH) and SU1DZ (9K2DZ), while others, such as SU1MR and SU1SR, route QSLs through SU1ER. The list also contains details for operators with international home calls, including SU2RS, who QSLs via OE6EEG. This resource serves as a basic callbook for the Egyptian amateur radio community, offering essential contact information for local and international hams seeking to confirm contacts or establish communication.

This interface is intended to be used with all the popular digital modes like PSK31, RTTY, Olivia, etc., which modulate a continuous carrier.

Echolink, EQSO, Echostation, SSTV, WEFAX, PSK-31 other digital sound card modes

An off centre fed dipole, with 10 feet of vertical radiator. It needs no tuner on 40m, 20m and 10m by M0UKD

Amateur Radio Projects & Kits for homebrewers, includes DDS,sound card interface,programmers, hamcom, frequency counter, RF Power Meter, modems and more.

Radioberry Radio hat for raspberry pi. HF (0-30 MHz) The latest development of PA3GSB is a radio card plugged into a raspberry pi (2 or 3) , a so called rpi-hat, forming an amateur radio.

A guide on writing reports to broadcasting stations and obtaining QSL cards

CARF combines the wonderful world of amateur radio with Christian fellowship and service

One point eight MHz to 30 MHz is the operational bandwidth for this 4:1 Ruthroff voltage balun, designed to interface an unbalanced T-Match network with a balanced antenna system. The project details the construction using a _T200-2_ powdered iron toroid core, tightly wrapped in PVC electrical tape for insulation, and wound with 17 double bifilar turns of 1.25mm enamelled copper wire. This outboard balun offers flexibility, allowing hams to trial various baluns based on antenna system and impedance characteristics, rather than integrating it directly into the tuner. The resource includes a schematic of the balun, a wiring diagram showing winding connections, and a table suggesting alternative toroid cores like the T80-2 or T400-2 with corresponding winding counts. Component sourcing is straightforward, listing items such as the _Amidon_ T-200-2 core, SO-239 connector, and a sealed polycarbonate enclosure from Jaycar. Performance evaluation was conducted using an _AIM 4170C_ antenna analyser, demonstrating efficient 1:4 voltage transformation across the specified HF spectrum. Further efficiency tests involved measuring RF power loss at various frequencies, revealing minimal loss—less than 0.7 dB from 3.6 MHz to 30 MHz, and only 2.0 dB at 1.8 MHz. These measurements, performed under ideal 50-ohm conditions, confirm the balun's effectiveness as a low-loss interface for multi-band antenna systems. The page also links to several other balun and unun projects, including 1:1 current and voltage baluns, and 9:1 voltage ununs, providing a broader context for impedance matching solutions.

DOS Hellschreiber radio program by G3PPT

Generates Morse tones using the Soundcard. A neat tool for sending out short sequences of Morse tones.

The SDR-908 is a software defined radio designed specifically for portable use, without the bother of being tethered to a PC or soundcard for the modulation/demodulation processing performed in this kind of radio.

Amateur radio cartoons by Woody Epp W7EPP

Rock Hill SC Hamfest on Oct 6 at Knights Stadium Exit 88 off I-77 Giant paved fleamarket, VE testing 10 AM, Talk-in 147.03 -600 Open 6 AM

Presents a QRP AM/CW transmitter project specifically designed for the 10-meter band, utilizing a crystal oscillator and a collector-modulated AM oscillator. The design employs a 2N2219(A) transistor in a Colpitts configuration, generating 100 to 350 mW of RF output power depending on the 9-18 Volt supply voltage and modulation depth. Frequency stability is maintained by a 28 MHz crystal, with fine-tuning possible via a Ct1 trimmer capacitor for approximately 1 kHz adjustment. The resource details the RF oscillator stage, implemented with a 2N2219 NPN transistor, emphasizing frequency stability and low power dissipation. It also covers the amplitude modulation stage, managed by a 2N2905 PNP transistor, which impresses audio information onto the carrier. Selective components (C3, C4, C7, C5) enhance voice frequencies within a +/- 5 kHz bandwidth, and modulation depth is controlled by R2 and R3. The project includes a 3-element L-type narrow bandpass filter (Ct3, L3, C10) to suppress harmonics and ensure a clean output signal. The project provides a complete schematic diagram, a comprehensive parts list including specific capacitor, resistor, and inductor values, and construction notes for the coils (L1, L2, L3). It also offers practical advice on enclosure requirements, suggesting an all-metal case or a PVC box with graphite paint for RF shielding. Operational parameters such as current draw (27mA@9V to 45mA@16V) and input impedance (50 Ohms) are specified, alongside guidance on antenna matching and the importance of a valid amateur radio license for 10-meter band operation.

5W portable solar charger project that uses both your ham and carpentry homebrewing skills.

The ZS6BKW multiband antenna, an optimized variant of the classic G5RV, features a 102-foot (31.1 m) horizontal span and a 39.1-foot ladder line matching section. This design, derived by G0GSF (formerly ZS6BKW) in the early 1980s using computer programs and _Smith charts_, aims for improved SWR across multiple HF bands compared to its predecessor. Construction details specify Wireman 554 ladder line and #14 AWG THHN copper wire for the radiators, with precise instructions for determining the velocity factor (VF) of the ladder line using an antenna analyzer or dip meter, ensuring accurate physical length for the matching section. The radiator length is electrically 1.35 wavelengths for the 20-meter band, requiring careful trimming during tuning. Field measurements with an _AIM-4170C_ analyzer by KI4PMI and NC4FB demonstrated good SWR curves and bandwidth on 6, 10, 12, 17, 20, and 40 meters. The antenna was deemed unusable on 15 and 30 meters due to very high SWR, but an LDG AT-100PRO autotuner successfully brought 6 and 80 meters into tune. Contacts were made on 80, 40, 20, and 17 meters, including a **17-meter** contact to Spain. EZNEC models for 80-6 meters are provided, along with an AutoEZ model by AC6LA, which predicted good SWR for 80-10 meters. W5DXP's modifications for an all-band HF ZS6BKW are also referenced.

conversion of low band VHF AWA 25M-1 carphone onto 6 metres.