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Excellent guide to using ferrite cores for interference suppression. Understanding and Solving RF Interference and Noise Problems by Jim Brown K9YC Audio Systems Group, Inc. PDF File

Using delta match with HF antennas design

PDF resources containing information on low cost ssb,am,cw circuits, which are useful for beginners.

A guide for users of Ubuntu amateur radio software General support of Amateur Radio using Ubuntu /Linux.

Lets you automatically record your favorite radio programs from Web Radio broadcasts, and then listen to them later on your PC, MP3 player or Pocket PC.

Gi7b is tube designed for microwaves but working good as HF amplifier. Idea is to build cheap, reliable HF amplifier covering 160 meters band.

A DDS VFO using the Arduino Uno platform

Installing these filters is a big improvement in the quality of the rig of the Yaesu FT-897D

Using the FT-857 Microphone Jack for Serial Control (CAT)

Improvements to Using the Heath SB-200 Linear on Six Meters by Ron Klimas, WZ1V

Post with opinions on the Yaesu FT-897

Essential tower tool invented through necessity.

The sun can power your Ham station and a whole lot more. Using solar power panel with a 12 volt battery can permit you to operate autonomously even for several hours without interruption.

Putting up wire antennas is always a fun proposition. Sometimes it is fun for the participants and often fun for on-lookers. There are at least as many methods as there are folks putting up antennas.

How to adjust your SWR on your radio and why.

Improper grounding or earthing system can cause several unwanted RF interferences (RFI) to television sets, broadcast receivers, hi-fi sets and telephone sets. In this Article the author explain how to setup a proper radio shack grounding using coaxial cable and ceramic disc capacitor

The **United States Islands (USI) Awards Program** is an amateur radio operating activity centered on activating and chasing islands located within the fifty states of the United States, its territories, and protectorates. These islands encompass coastal shores, lakes, rivers, ponds, and streams, offering a diverse range of operating environments. The program provides numerous achievement awards for both island activators and island chasers, encouraging portable operations and mini-DXpeditions. Participants engage in year-round activities, including the **One-Day-Getaway (1DG)**, a casual portable operation held on the second Saturday of May, and the U.S. Islands QSO Party (IQP), a 15-hour contest occurring on the last full weekend of August. USI encourages hams to discover and operate from islands in their local areas, providing an alternative to traditional Field Day operations for outdoor radio enjoyment. The program supports various operating styles, including portable, walk-on, paddle-to, motor-to, mobile, and drive-on activations. Recent activities include AC1RH activating MA064R Eagle Island daily, aiming for over 100 activations using 600 watts, and KD9ZAB and KD5YZY qualifying MO021R Tower Rock, which is also a POTA US-10147 location. The USI program maintains a clear distinction from the Islands On The Air (IOTA) awards program.

Yaesu FT-2000 Panadapter, using the Softrock 9 Lite, SDR receiver kit

2 Meter Slim Jim Antenna Using 300 Ohm Twinlead

The instructions listed here show you how to set up a Raspberry Pi for use as an RTL-SDR dongle server

A conversion of a 80m dipole into a 160m vertical antenna

Manufacturer of pultruded fiberglass shapes,

4CX1500B RF amplifier schematic, working 1.8 MHz to 29.7 MHz

Notes on using RG-174 Coaxial Cable at Medium and Lower HF Frequencies by John Bryant and Bill Bowers

How to homemade a multi-band HF dipole using 100 meter of speaker wire, 2 strandsm including a homebrew 1:1 choke balun

Michigan area radio enthusiasts, inc. is a non-profit club of swls, dxers, scanner buffs and general radio nuts, serving radio hobbyists with schedules, discussion groups

Notes on using the QST propagation charts to determine propagation conditions

Interface APRS to a weather station

An interesting article about planning and testing beverage antennas for 80 and 160 meters in a rural location

With spectrum analysis of beacon signals, it's possible to see features relating to various propagation phenomonen.

Cutting out the noise using a simple coax filter to improve the poor front end filtering

Clean Up Your Signals with Band-Pass Filters

There are several reasons that can cause coax line radiation, most of them are related to wrong or missing use of a balun, but none can be imputed to load mismatch.

NVIS antennas, also known as Near Incident Vertical Skywave antennas have a high angle of radiation. Something on the order of 60 degrees, to straight up to 90 degrees. A portable, easy to setup and cheap nvis antenna project.

With the bluecat interface it is possibile to connect a Yaesu FT 817 857 897 to a computer or a android smartphone without any cable or interface, using a bluetooth wireless connection

Short description of the olivia mfsk mode and explanation of how to use olivia mode and proper radio setup including recommended olivia frequencies

Connecting rhythm and language with Morse Code by Phil and David Tulga

Adapting a Wouxun/Kenwood USB cable as a Yaesu FT-817 FT-857 FT-897 CAT connection

A 600W 1.8 MHz to 54 MHz power linear amplifier made using rugged MRF300 transistors featuring output power between 580W and 750W depending on band, power supply: 48V, 18A typical, 20A max

Resources for custom battery chargers and power supplies from powerstream

The article, "Using 75 Ohm CATV Coaxial Cable," details methods for employing readily available 75-ohm CATV hardline in standard 50-ohm amateur radio setups. It addresses the inherent impedance mismatch and practical considerations, such as connector compatibility, for hams seeking cost-effective, low-loss feedline solutions. The resource specifically contrasts common 50-ohm cables like RG-8, RG213, and _LMR-400_ with 75-ohm hardline, highlighting the latter's lower loss characteristics, particularly at VHF and UHF frequencies. It explores two primary approaches to manage the impedance difference: direct connection with an acceptable SWR compromise and precise impedance transformation. The direct connection method acknowledges that a perfect 1:1 SWR is not always critical, especially when using low-loss coax. For impedance transformation, the article explains the use of half-wavelength sections of coax to reflect the antenna's 50-ohm impedance back to the transmitter, noting its single-frequency effectiveness. It also briefly mentions transformer designs using toroid cores and a technique involving two 1/12 wavelength sections of feedline for broader bandwidth. The content further clarifies the concept of _velocity factor_ for calculating electrical versus physical cable lengths, providing a generic formula for precise length determination. It notes that while half-wave matching is practical for 10 meters and above, it can result in excessively long runs for lower bands like 160 meters, potentially adding **250 feet** of cable. The article also mentions achieving a usable bandwidth of 28.000 MHz up to at least **28.8 MHz** on 10 meters with specific transformation techniques.

G0KYA MMANA-GAL presentation and samples

Linear amplifiers cold adjustments with network analyser (VNA)

How to program Baofeng handheld transceiver with satellite frequencies, and how to get alerts when satellites are visible by using a smartphone app. A beginners guide to work satellites with a common VHF handheld radio.

1:49 UNUN using two stacked FT240-43 cores for end fed halfwave antenna. To match the end fed half wave antenna to the coaxial feeder, it is necessary to have a matching network or transmission line transformer.

A tutorial on using RF frequency counter, how a digital frequency counter works, includes frequency counter specifications and best practices in setting counter accuracy and resolution

Southeast Georgia island hoppers

A very popular method of making a short dipoles resonate at a given frequency. This type of antenna is suitable for single band, narrow bandwidth use.

Article on Phase-cancellation of noise on 2m band

A nice presentation for beginners by Radio Club of Tacoma