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A SSTV interfsace (soundcard) to minimize RF feed back and a soundcard limiter to prevent over driving the soundcard

Home made 40 meter transceiver project. The receiver is a Progressive Receiver with a few modifications. The Transmitter is a modified MFJ Cub circuit. Includes schematic and circuit diagrams for Receive Input Filter, 3-Pole 500 Hz Cohn Filter and 7 MHz Double Tuned Bandpass Filter

Sint Maarten by K1GI (PJ7I) 7L4DXT (PJ7XK) - 18 to 24 Nov 2012

A home mande spectrum analyzer project with several pictures and disposition of components boards based on a project by S57C

This page describes a printed circuit board that you may use to build a QRP keyer.

Icom IC-R9500 Professional Receiver with 5 roofing filters, 48 kHz DSP

Elkhorn Valley Amateur Radio Club Norfolk

The "Beginner’s Guide to Small-station EME" by Paul Bock, K4MSG, offers an insightful look into Earth-Moon-Earth communication, a fascinating aspect of VHF and above amateur radio. This presentation demystifies moonbounce, explaining how two-way radio contacts are made by reflecting signals off the Moon. K4MSG highlights the historical context of EME, noting the substantial investment and technical challenges that once characterized these operations, often requiring setups like the W5UN "Mighty Big Array" (MBA). Historically, path loss exceeding 250 dB, spatial polarization offset, Faraday rotation, and galactic noise made EME a formidable pursuit, with CW being the mode of choice for signals that had to be audibly detectable. Equipment limitations in noise figure and coax performance further compounded the difficulty for early moonbouncers. However, the landscape of amateur EME dramatically shifted around 2003 with the introduction of the JT65 software. This innovation, specifically designed for EME, allowed for signal decoding well below the noise floor, making small-station EME a practical reality for more hams using common transceivers and less complex antenna systems.

A collection of QSL cards from and old operator, Art J. Cook, VE4KZ, who lived in Calgary Alberta, that contained some from the far north of Canada.

This page includes an interesting and comprehensive review of the ICOM IC-7300 SDR HF / 50 MHz transceiver. The author focuses on many aspects of this transceiver with impressions based on his experience

DL7AFS, Babs and DJ7ZG 5-19 November 2012

QSLinfo.de is a QSL manager and address database for radio amateurs, maintained by Lothar, DL1SBF for more than 25 years already.

Review of the ICOM IC-R9500 Wide Band DSP Receiver

Departamento de Radio Escutismo do Nucleo Moinhos de Vento Portugal

What is a QSL Card and what should be the content of each QSL card, collecting cards, electronic QSL LoTW eQSL, QSL Bureau, and QSL managers.

Free PDF book to start learning morse code and to improve your proficiency, freely available in four languages english, german french and italian.

A guest review of the FLEX-6400M DSP HF Trasnceiver considering just the receiver part of this radio.

Official download page of TQSL software provided by ARRL as LoTW signing tool to upload QSO confirmations valid for ARRL Awards. TQSL download page provide links for Windows MacOS and Linux platforms.

International Police Association Radio Club, OO6P

Transmission lines have many uses other than simply transferring RF power from one point to another. Impedance matching, baluns and filters are probable the most common of these.

A QSL Cards collection divided into North American Shortwave Pirate Radio QSLs abd European Shortwave Pirate Radio QSLs

A single coil Z-Match. This QRP version by G3WQW, using a T130-2 toroidal inductor and polyvaricon variable capacitors was published in Sprat 84.

Here are some hints and tips for construction of a good preamp for satellite work.

Documents the design and construction of a **four-band Moxon beam** antenna, covering 20, 15, 10, and 6 meters. Author W7JMP shares his journey from initial research and computer modeling using 4NEC2 to the final on-air testing and optimization. The project aimed for gain over a dipole on 20 meters, with a budget under $500, including the antenna rotor. The design incorporates fiberglass spreaders and a single feedpoint, avoiding complex relay switching. The article details the selection of materials, assembly techniques, and the critical tuning process. W7JMP describes fabricating the hub, mounting spreaders, and attaching elements made from stripped THTN wire. A notable innovation is the use of a half-wave tuning stub with a loading coil for in-situ adjustment of the 20-meter reflector, optimized via remote S-meter readings using a webcam and smartphone. This method allowed for fine-tuning the **front-to-back ratio** without lowering the antenna. Initial testing revealed a dipole-like pattern, which was significantly improved after tuning, resulting in reported 2 to 4 S-unit front-to-back ratios and enhanced signal strength for DX contacts on multiple bands, including sporadic E on 10 and 6 meters.

Personal web site by N9SKN about portable QRP operations with pictures of several portable setups and antenna solutions.

The high-frequency inductance of single-turn loops of various shapes made of round wire can be estimated accurately with a simplified formula

Review of the 150 kHz to 30 MHz Ten-Tec receiver

Documents the A35EU DXpedition to Tonga, specifically targeting the _IOTA OC-049_ Tongatapu group during 2018. The resource outlines the operational bands from 10 to 160 meters and the primary modes utilized, including _CW_, _SSB_, RTTY, and FT8. It provides essential information for DXers interested in confirming contacts with this rare entity, detailing the logistical aspects of the operation and the specific island group activated. This page serves as an archive for the A35EU operation, offering QSL update information and confirming that all log queries were processed and a fresh log uploaded to _Clublog_. Such details are crucial for operators seeking to verify their contacts and apply for awards like DXCC or IOTA, providing a definitive record of the expedition's activity and post-operation administrative status.

For low voltage applications, like cathode bypass capacitors, most vintage types have an axial configuration, which is less common today but still available. Electrolytic power supply caps likely constitute the single worst liability in old audio, radio and test equipment. Rap about Electrolytics, Reforming, Chassis-Mount Replacements, Under-Chassis Installation, Rebuilding Capacitors

Collection of modifications for the Retevis RT3, a monoband handheld transceiver for DMR (digital voice) and analog FM. It is almost identical to the Tytera MD-380.

KB3IFH Full Color quality QSL & Eyeball cards. Free custom design & imaging scanning, based in Hampstead, MD USA

Purchase full color QSL cards at single color pricing. Quality and value in fully customized, full color, photo QSLs with discounted re orders!

The Shrunken Quad antenna is a unique design that offers full-sized performance on the 10m and 15m bands while incorporating linear loading via a trap for operation on the 20m band. This design allows for effective communication in the HF spectrum, making it suitable for both casual operators and serious DXers. The quad configuration provides excellent gain and directivity, which is beneficial for contesting and long-distance contacts. Constructing the Shrunken Quad involves careful attention to dimensions and materials to ensure optimal performance. The antenna's compact nature makes it an excellent choice for limited space situations, allowing operators to enjoy the benefits of a quad without the need for extensive real estate. This project is ideal for amateur radio enthusiasts looking to enhance their station's capabilities with a versatile and efficient antenna system.

TNXQSO.com offers a streamlined **log search** utility, specifically designed to consolidate QSL information for **DXpeditions** and special event stations. This online service aggregates data from prominent logging platforms such as Club Log, Logbook of The World (LoTW), and HRDLog, presenting a unified interface for radio amateurs to verify their contacts. The platform aims to simplify the process of confirming QSOs by providing direct links to the respective logging services, allowing users to quickly ascertain if their contact has been uploaded and confirmed. Users can input a callsign and band to retrieve immediate results, indicating whether a QSO is present in the linked logs. The service also supports DXpedition teams by offering tools for managing their own logs and QSL routes, without requiring an account for general log searching. This functionality proves particularly useful for DXers seeking rapid confirmation of rare contacts or for those managing their QSLing efforts across multiple platforms after a significant operating event.

An attic wire antenna with several modifications during the time. Began as a simple coax fed doublet antenna, and upgraded to a multi-band hf fan dipole, till the G5RV all deployed in an attic.

Discussion about laterally bent-end dipoles. Bent by percentage of length and fine-tuned by angling the bent ends.

Discussion about the Standard Horizontal, Center-fed dipole and effects of elevation of the antenna on antenna radiation pattern.

Provide your radio with a very string signal, then adjust the HIGH LEVEL pot to the threshold of illuminating the last LED (all LEDs on).

This page provides construction details for a 4-element 10-meter Yagi antenna with 28 Ohm impedance. It includes information on the elements, positions, diagrams, and data related to frequency, gain, front-to-rear ratio, radiation resistance, SWR, and loss. The content is aimed at hams or radio operators interested in building and optimizing Yagi antennas for the 10-meter band.

Affordable full color QSL card printing. Premium quality offset printing with gloss, spot UV, and foil coatings.

This is a plan for an optimized element UHF Yagi Antenna for UHF Bands featuring a 9dBd forward gain, a 13 dB front-back ratio, and a bandwith of 10 MHz on the 430-440MHz range.

How to use a little known J-antenna characteristic to reduce a conventional 14 foot antenna to 7 feet. Perfect 50 Ohm match, same gain, no radials.

The Pocket Portable J-Pole Antenna, a neat little project that will prove useful for portable operation or improving your HT in the fringe areas.

The exchange of QSL cards by radio amateurs is a practice that is almost as old as radio itself. History of IARU QSL Bureau, evolution of the system

KM Rover is a rover logger software for BIG 4 VHF UHF contests and generic, Spring and Fall Sprints, GPS interface, beam heading CW PTT DVK functions. Works on Windows

This page show a list of repeaters in north america transmitting from 28 MHz to 29 MHz. The most of them are in the 29.620 to 29.700 frequency range. Some repeaters may be active and on the air while others may not

The Smith Chart, named after its inventor Phillip H. Smith, is a graphic tool used to solve transmission line problems in the field of ham radio operations. By using the Smith Chart, ham radio operators can determine the feed point impedance of an antenna, design impedance-matching networks, and optimize power transfer between a source and its load. The chart consists of resistance and reactance circles, providing a visual representation of complex mathematical relationships related to transmission line operations. Understanding and utilizing the Smith Chart is essential for hams looking to enhance the performance of their RF circuitry.

Inverted L antenna, even if not completely freestanding, it only requires one line to be lauched into a tree to support the end of the horizontal wire. This project is done with a 31-foot Jackite pole for a support and uses six 15-foot radials and one 33-foot radial.

Online QSL archive counting 13400 QSL scanned and indexed online with a searchable database

G6HKS Yagi Kits & Parts provides material kits for building high-performance PowAbeam Antennas, ideal for VHF/UHF enthusiasts interested in DXing. The kits feature advanced Yagi designs, including the unique ParAclip system, ensuring exceptional all-weather stability and minimizing detuning effects. With resources, tips, and support, the site aims to make antenna construction straightforward for amateur radio operators. The focus is on delivering top-tier performance at competitive prices, empowering users to build and enjoy their own high-quality antennas.