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This program descrambles band inverted encrypted transmissions, usually found on VHF/UHF. It uses a NCO (numerical controlled oscillator) to re-produce the originally inverted audio band.

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.

Ham Radio applications with the Arduino micro-controller presentation

An horizontal full wave wire loop antenna for the 80 meters band by W4HM

The ITU and CQ Zones Map is a printable two-page PDF provided by Icom, displaying the world divided into ITU and CQ Zones. The purpose is to assist radio amateurs in identifying and understanding these zones for communication purposes.

WA2UGT X-beam antenna for 17 meters band

Presents G0GSF Brian's ZS6BKW antenna, a refined iteration of the classic G5RV, offering improved performance across multiple HF bands. The design emphasizes specific radiator and ladder line lengths to achieve lower SWR on 40m, 20m, 17m, 12m, and 10m, making it a practical choice for operators seeking a single wire antenna solution. The document includes critical dimensions for the flat-top and the 450-ohm ladder line section, which are key to its multiband resonance characteristics. Unlike the original G5RV, the ZS6BKW aims for direct 50-ohm feedpoint impedance on several bands, reducing the need for an external antenna tuner. My field experience with similar optimized dipoles confirms that precise construction, particularly the ladder line length, is paramount for realizing the intended SWR benefits. This design offers a compelling alternative for hams with limited space or those preferring a less complex antenna system.

Based on a W4TWW project and modified by KN4LF

A Quad Fractal Antenna for 20 meters band by F3DD

This article describes a simple, inexpensive, dipole antenna that will rival the performance of a ten-meter beam.

adsbScope is a freeware Windows application designed for processing _ADS-B_ (Automatic Dependent Surveillance-Broadcast) frames received from a compatible decoder. It identifies aircraft, calculates their real-time positions, and presents flight parameters in both alphanumeric tables and a graphical display. The software interfaces via a virtual COM port, receiving raw frames to provide detailed situational awareness, including a global coordinate grid, continental coastlines, over 4,000 **airport** locations, and major cities. Users can overlay OpenStreetMap tiles and view world state boundaries, with each tracked aircraft rendered with labels showing altitude, speed, heading, squawk code, and flight identifiers. When paired with the adsbPIC-decoder, adsbScope enables advanced hardware control, allowing users to toggle data filters for specific frames like DF17/18/19, adjust analog signal thresholds for reception fine-tuning, and manage system resets or bootloader activation directly from the PC. This functionality provides a customizable toolkit for hobbyist radar listeners, offering a robust alternative to commercial tools for processing aircraft data. The software displays up to **1090 MHz** transponder data and can track aircraft up to 250 nautical miles.

NuMorse 2.20.0.0 for Win 7/Win 8/XP/Vista/Win 10 A complete rewrite of the original NuMorse used by thousands of radio amateurs to gain and upgrade their licenses. NuMorse offers an intermediate feature set that is somewhere between the lean and mean NuCode program and the vast array of features supported by NuMorse Professional. But NuMorse is no cut-down program. It has several unique features not found in other Nu-Ware products as well as a compact and intuitive set of controls that you will be able to learn quickly.Product is no more developed and out of support.

Freeware Hellschreiber decoding program for windows by Nino Porcino

Phased array Ground Planes antennas for 144 Mhz

Phased arrays of short vertical antennas. A technical notes from Butternut antennas on phased vertical arrays

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

Download ex1726 a 32-bit DOS radio control program for the ICOM M700PRO, M710 and M710-R NMEA computer interface.

The original G5RV antenna system consists of a center-fed horizontal 102' wire plus a 34' length of open-wire 525-Ohm feeder. Louis Varney, the antenna system's developer, intended two other features. Learn more at Cebik website

Radio Incident Command Kit project is described in this article loaded with many pictures and go-kit composition.

Mose Trainer by G4FON is a free windows morse code training program developed using the Koch method. Sends words simulating real morse code transmission, with QSB and QRM, allow change speed tone and many other settings. Download the kochmorsetrainer_install file and start learning Morse Code.

A 40-meter reversible _Moxon rectangle_ antenna project details its construction and performance, featuring 51-foot long sides and 7.7-foot turned-in sections. The design incorporates a 16.5-foot boom, with elements spaced 1.1 feet apart, constructed from #14 covered wire. It utilizes two double-pole relays for switching between NE and SW directions, achieving F/B ratios up to 40 dB on CW and 30 dB on SSB, with distinct reflector stub settings for each mode. This antenna replaced a full-size 2-element Yagi, demonstrating comparable forward gain while offering superior F/B ratios and directional flexibility. _EZNEC_ modeling indicates only 0.2 dB less forward gain than the Yagi. The system uses no baluns, relying on half-wave feedlines and switched stubs for impedance matching. The antenna is tree-supported at 45 feet, with its effective radiation height modeled at 80 feet due to local terrain, enhancing its performance over a nearby lake.

Making a 4:1 balun with a nescafe coffee jar lid and a toroid

A free to download and print, log sheet in A4 paper format for amateur radio stations

This very large moxon antenna resonate on 80 40 and 10 meters, has been used for CQWW 2006 by a YU team project

A shortened multiband antenna, about 23m long, for 80m - 10m bands with a low SWR (<1.3) on 80m and 40m, and < 3 till 10m. Bandwith on 80m is 300kHz

CWCom is a free morse code chat progam for Windows operating systems you can download free. Has been tested with windows 10. You can use CWCom to transmit and receive morse code and text messages over a LAN or even across the internet. CWCom can translate and decode morse code to text and encode text into morse code or flashing light, so you don't have to know morse code to use it.

The varieties of twinlead J-Poles and some performance standards, L. B. Cebik, W4RNL

46ft multi-band antenna for small gardens. Works well on 80m. An excellent DX performer and is an ideal replacement for your half size G5RV

The total length of the inverted L is 240 feet, which is 7/16th of a wave length long. It has a 92 foot horizontal linear load section 1 foot above ground that terminates into a home-brewed parallel network tuner by KN4LF

Designing quagi and yagi antennas on 2 Meters, some preliminary notes by Cebik, W4RNL

A Primer for the new Packet Radio operator

Comprehesive page on TS-940 TS-940 reference maintained by ZL4AI Jeff

Portable Vertical Antenna for 75m and 40m featuring Low radiation angle for DX, easy to install and to match 50 ohms

Great first time J-pole project. Covers most of the basics. This small and thin design also makes it good for several stealth applications.

Inline RF Power & VSWR Meter. A DIY meter 0 to 30 Watt with Average and Peak. Circuit Description, Arduino Nano software code and part list to DIY your own Digital SWR Meter

A web site offering a QRZ.com integrated mapping service. Allows creating a google map of your QSOs adding a list of QSOs manually or importing an ADIF log file. Registration and a QRZ.com account is required.

This free PDF file contains two Worldwide grid square maps. The first map displays the fields (first two letters of a maidenhead locator) while the second includes also squares (third and fourth digit) and it can be useful to determine what is your ham radio grid square. PDF file can be enlarged and scaled to A3 and higher dimensions.

This PDF document, authored by KT4QW in October 2004, details the construction and modeling of a dual-band, horizontally polarized hanging rectangular loop antenna for **10 and 17 meters**. The design, adapted from *The ARRL Handbook*, utilizes _NEC4WIN95_ software for scaling and optimization, targeting a 50 ohm feedpoint impedance. The resource includes a bill of materials, step-by-step construction instructions, and a discussion of the antenna's radiation characteristics. It presents NEC-generated elevation and azimuth patterns, comparing the loop's performance to a half-wave horizontal dipole at the same height and frequency. The 17-meter element is centered at 18.140 MHz for low SWR across the phone band, while the 10-meter element is centered at 28.500 MHz. Construction involves 14-gauge stranded copper wire and Schedule 40 PVC spreaders, with the total wire length calculated by the formula: Length in feet = 1005/MHz. The feedpoint impedance can be adjusted by modifying the rectangular aspect ratio. The document specifies hoisting the antenna to at least a half-wave above ground for testing. It notes that a balun was tested and found to have no measurable effect on SWR or radiation characteristics. A 2-meter scale model is presented to illustrate the physical design, and a "rotator" string is incorporated for directional adjustment up to 90 degrees.

70cms Simple Moxon 2 elements antenna

A coaxial cable tuneable magnetic loop antenna for 7MHz. This experimental antenna does not require a tuning capacitor

The document discusses a two-element parasitic Delta-Loop array for the 40 meters band, aimed at radio amateurs interested in antenna projects. It provides detailed plans and instructions for building a homemade Delta-Loop antenna.

Freeware software that synchronize your PC's clock. Dimension 4 monitor your Internet connection and automatically adjust your PC's clock when you're online at an interval you specify. Windows version only.

These inexpensive, easily built filters can be the buffer you need between the signals you want to hear and send and those you don't!

If you can't get on the air from home, the Internet may provide the answer. By Brad Wyatt, K6WR. Pdf File.

A potpourri of 160-Meter vertical antennas and modeling issues, inverted-L, 3-element parasitic array, 1/4-wavelength monopole

KN4LF article about a 1/4 wave fan inverted L antenna for 80 and 160 meters band

A free to download and print, paper log sheet for shortwave listerners in PDF format.

Using moxon rectangles for WARC-Band antennas

N0KHQ Moxon rectangle for 17 meters, constructed from RG-58 coaxial cable

Why the G5RV is a good antenna on 75m and 40m