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A comprehensive list of what is on the frequencies between .5 MHz and 5,000 MHz

Live streaming audio of VHF marine radio channels 05A, 16, and 22A from NJ and NY City

Online computer-based training for the amateur radio written exams

How to build a beverage antenna. How to deploy a BOG antenna for your next SWL DX-ing activity. Give it a try and follow the orientation tips for this bi-directional antenna.

Canadas Amateur radio, citizen band , shortwave, scanners, marine radio distributor and manufacturer of ham radio accessories

One common challenge in antenna systems is mitigating common-mode current on the feedline, which can distort radiation patterns and introduce RF in the shack. This project details a 1:1 balun design that ingeniously avoids traditional ferrite beads, often a costly component, by substituting them with steel wool. The steel wool, when integrated into the balun's construction, effectively attenuates unwanted RF on the outer braid of the coaxial cable, ensuring that the antenna radiates efficiently and as intended. The construction involves winding coaxial cable through a PVC former, with the steel wool strategically placed to provide the necessary common-mode impedance. This method offers a practical and economical alternative for hams looking to build effective baluns without the expense or availability issues associated with ferrite cores. The design principles focus on creating a balanced feed to the antenna, crucial for optimal performance of dipoles and other balanced radiators. Experimentation with such designs can lead to improved field results, particularly for those operating with limited budgets or seeking innovative solutions for their antenna systems. The simplicity of using readily available materials like steel wool makes this a compelling build for many radio amateurs.

Design your own quadrifilar helix, the site even generates a drilling pattern in a PDF file. Several different construction methods are shown.

K0JD's home construction projects, featuring the R2/T2 modules by KK7B

The W8JK is a famous and effective DX antenna, first built by John Kraus, W8JK, in 1937. A Beam antenna with two parallel dipoles driven with opposite phase, with a close spacing of an eighth of a wavelength.

This is a hex beam designed for six meters. It has three elements with a turning radius of 54 inches. This antenna can be built from low cost materials available from the local hardware store. By WB3BEL

These are 200 Morse Code QSO`s which might typically be heard on the HF bands.

Stryker Amateur radios offer great performance and unique features. We pride ourselves with offering affordable radios that are built with quality and performance in mind.

Operating amateur radio satellites effectively requires precise knowledge of their orbital mechanics and pass times. Gpredict, a real-time satellite tracking and orbit prediction application, addresses this need by allowing operators to monitor numerous satellites simultaneously. It displays critical data such as position and pass details through various visualizations, including lists, tables, maps, and _polar plots_. Unlike many other satellite tracking programs, Gpredict introduces the concept of visualization modules. These modules enable users to group satellites and configure each group independently, offering unparalleled flexibility in how orbital data is presented. This modular approach supports tracking satellites from multiple observer locations concurrently, which is particularly useful for stations with diverse antenna setups or remote operations. Originally a GUI client for John Magliacane's _Predict_ program, Gpredict evolved to integrate its own tracking code for improved performance. The software is distributed under the GNU General Public License, ensuring it remains free and modifiable for the amateur radio community.

Sams Photofact downloads - Schematics and Service Manuals for Radios, Amplifiers, More

An introduction to PSK31, MT63, and Hellschreiber, John DeGood NU3E Trenton Computer Festival in PDF

Specialized, business and industrial radios

Licensing, cost, practical applications, emergency and personal uses and famous hams.

Listen to Clearwater, Florida police including Pinellas County Fire, EMS as well as Pinellas County Sheriffs Department

Dire Wolf is a software soundcard modem and APRS encoder/decoder. It can be used stand-alone to receive APRS messages, as a digipeater, APRStt gateway, or Internet Gateway (IGate). It can also be used as a virtual TNC for other applications such as APRSIS32, UI-View32, Xastir, APRS-TW, YAAC, UISS, Linux AX25, and many others.

Wholesale distributor of CB radios, parts, antennas, microphones, power supplies, crystals, echo boards, expanders, meters and CB accessories.

Satellite Tracking/Orbital Prediction Program an open-source, multi-user satellite tracking and orbital prediction program written under the Linux operating system by John A. Magliacane, KD2BD. PREDICT is free software

John talk about Yaesu VX-3 as an interesting upgrade from VX-2, other reviews cover Kenwood TH-D7 TH-6A Icom-91A Kenwood TM-D700A Yaesu FT-817 and Icom IC-7000

Helical antennas invented by John Kraus give a circular polarized wave. They are one of the easiest to design. Find a tube with a circumference equal to one wavelength, and wrap wire in a helix spaced a quarter wavelengt

Presents a detailed construction guide for a **Quadrifilar Helix Antenna** (QHA) optimized for 137 MHz, specifically for receiving weather satellite transmissions. The resource outlines the author's experience building previous QHA designs, highlighting challenges with tuning and nulls, and then focuses on a refined design by John Boyer, documented by Steve Blackmore, which proved easier to build and yielded superior reception. The guide provides precise element dimensions, including 1.5m of 32mm PVC pipe for the mast and 8mm soft copper tubing for the helix elements. It specifies lengths for horizontal tubes (190mm, 90mm) and helix elements (903mm, 1002mm), along with instructions for drilling, assembly, and forming a **balun** by wrapping RG58 coax around the mast. The text emphasizes critical steps like ensuring elements are square and twisting in the correct direction to avoid phase issues. It includes references to original QST articles by Buck Ruperto (W3KH) and the WxSat program for decoding satellite transmissions, contextualizing the antenna's purpose. The article concludes with a sample NOAA 12 image from September 1998, demonstrating the antenna's reception capabilities.

G3WZT John Matthews project of a 600 Watt solid state linear amplifier for the 6 meters band

G4PDQ's PacketCluster routines to make PacketCluster a little more interesting for the user and a little easier for the SysOp

Information on contesting with CW and QRP

York, PA, hamfest and computer show

An email list for the discussion of the Kenwood TS-120 transceiver.

Antique Radio Schematics and Service Manuals for Tube Radios

An old post by John Doty about effects of noise in longwire antenna.

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.

Details Guglielmo Marconi's foundational contributions to radio communication, highlighting his 1898 Patent **7777** which introduced tuning circuits for independent simultaneous communications. Chronicles the historic transatlantic reception of the Morse code letter 'S' on December 12, 1901, from Poldhu, Cornwall, to St. John's, Newfoundland, a distance of over _3,500 kilometers_. The exhibit showcases early Marconi 10-inch spark transmitters, identical to those used on the _Titanic_, alongside Canadian Marconi crystal detector models. It also features high-end commercial receivers like the IP501, weighing **87 pounds** and originally priced at $595.00, demonstrating the robust construction and technological advancements of the era.

Wood and plastic broadcast radios from the 1930s and 1940s, lovingly described and profusely illustrated.

Annual Cherryville Repeater Association Hamfest, North Hunterdon Regional H.S., Route 31 South, Clintion Twp USA

FT-1000MP series radios solid-state replacement for the CFL backlight. Eliminates the delay and brightness issues. Works on MKV, MKV Field, and 1000MP radios.

A Smith charting program. You can enter either discrete components or transmission lines, see the results on screen and/or generate Postscript output. Component values can be changed numerically or using scrollbars.

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.

A range of easy-to-build RFI filters by John Regnault, G4SWX

How Vacuum Tubes Really Work. Vacuum tubes rely on hot cathodes emitting electrons and a plate attracting them to create current. A grid in between controls the current flow, enabling amplification. This article explores the nitty-gritty of how it works, including how cathode type, temperature, and electrode spacing affect the process. It explains the physics behind electron emission, space charge, and amplification factor, offering a deeper understanding than the basic principles.

A user group established by John Wiseman G8BPQ/GM8BPQ and Ron Stordahl AE5E (ex N5IN) for BPQ32 - AX.25 NET/ROM compatible node software for Windows.

Antique Radios of all kinds plus an operating ham station

Homemade hamstuf, mostly homebrew antennas in Dutch

An interesting article on how to make copper cactus J-Pole antennas

A step by step approach for a ham radio vertical antenna mount using only a hole, gravel and a piece of plumbing pipe

The JSCARC, located at NASA's Johnson Space Center, Houston, Texas, supports the U.S. Space Program and the International Space Station.

This article is about the characteristics and use of various filters and ferrites for solving amateur radio electromagnetic compatibility problems involving breakthrough of amateur signals into domestic equipment such as television sets, video recorders stereo sytems etc.

EB5AGV / EC5AAU Boatanchor collection. Useful data on TV-testers, Collins, Drake, Hammarlund, Hallicrafters, National, Heathkit, EF Johnson.

This site is dedicated to the repair, restoration, preservation and sale of old collectable radios, both bakelite and wood.

Satellite infos and links by Larry Johnston