Search results

Resistor Finder is a program that allows the electronics designer or hobbyist to find a combination of 2 resistors that, when connected in parallel, will provide the best match to a desired resistance.

PSK Express is a replacement for YGPSK, it is multi-mode and will allow you to use PSK, RTTY or MFSK at various speeds. Requires .Net framework and run under windows, freeware.

Demonstrates how to construct an automatic band decoder, moving beyond manual selector switches for antenna and filter control. It addresses the challenge of varying band data outputs from different transceivers: Icom rigs provide voltage values, Yaesu rigs use Binary Coded Decimal (BCD), and Kenwood rigs lack direct band data output. The resource highlights a clever solution utilizing logging software like _CT (K1EA)_ and _DX4WIN_ to emulate Yaesu's BCD output via a PC's printer port, making the decoder compatible with any rig. The author details experiences building decoders based on designs by Bob _K6XX_ and Guy _ON4AOI_, noting K6XX's simple TTL chip design and ON4AOI's more comprehensive, opto-isolated unit capable of controlling ten outputs and bandpass filters like the _Dunestar_. It also references a _W9XT_ board design, which Steve Wilson, G3VMW, modified with BD140 transistors for source drivers, emphasizing safety. The author successfully cased an ON4AOI-based decoder in an old modem case, connecting it to an FT1000MP or a PC printer port to drive remote relays and a Dunestar Band Pass Filter.

A magnetic loop antenna working from 30 to 15 meters with 100W

The FCC Lookup System software uses the standard FCC data files in an advanced lookup system for matching a call sign to a user. The software creates index files to allow rapid searches without modifying the FCC data file. Available for both Windows and Linux.

All about Chilean contest, awards, links and general news and DX from Chile

Club, Club station and Contest site for Radio Amateurs from Lier Belgium

The bass amateur radio IRLP group node 6391. victoria australia. info IRLP stands for the Internet Radio Linking Project. The aim of this project is to link radio systems separated by long distance without the use of expensive leased lines, satellites, or controllers.

The future of two way radio is digital.

Hamlib is a library aid for software developers wishing to incorporate control of amateur radio hardware into their programs. Hamlib will allow ham radio software authors to concentrate on the user interface and the basic function of the program rather than radio control.

Approximately 1,500 unique DX spots are typically visible on the _ODXC Web Monitor_ at any given time, providing real-time intelligence for amateur radio operators seeking DX contacts. This service aggregates spotting data from the _RW3XA-8 Obninsk DX Cluster_ node, presenting it through a straightforward web interface. Users can monitor current activity across various HF bands, identifying stations calling CQ DX or reporting rare entities. The platform supports both traditional telnet access for those using dedicated cluster clients and a Java-based web interface, catering to different operational preferences. It serves as a practical tool for contesters and DXers to track propagation, identify active stations, and plan their operating strategies. The cluster data includes callsigns, frequencies, modes, and spotter information, crucial for effective DX hunting. Integration with other spotting networks like _RBN_ and _PSK Reporter_ enhances its utility.

A 2 element small footprint 40 meter phased, reversible, downsized quad array antenna.

Interesting article on how build your own field day antenna

Club in Stoke On Trent, England specialising in training for all classes of Amateur licence in the UK.

Log2000 provides a structured environment for amateur radio operators to manage their contact records. This software facilitates the logging of two-way radio contacts, a fundamental aspect of the hobby, by capturing essential QSO data such as callsigns, dates, times, bands, and modes. It also supports the generation and printing of QSL cards and labels, streamlining the process of confirming contacts for awards and personal record-keeping. The program was specifically developed for Windows 95/98, Windows NT, and Windows 2000 operating systems. Its feature set includes tools for searching logs, generating various reports, and managing award progress. While tailored for earlier Windows versions, Log2000 offers core logging functionalities that remain relevant for basic station management.

This calculator is designed to give resistor values for unbalanced T-pads, and for balanced H-pads.

The Elecraft K2 transceiver requires specific modifications for optimal soundcard digital mode operation, particularly for PSK31. The original article, circa 2001, details initial challenges with manual PTT and speech compression settings. A key modification involves adding headphone audio and a compression disable signal to the K2's microphone jack, utilizing pins 4 and 5. The **COMP0** signal, active low, is shorted to ground via a non-inverting open collector switch circuit, comprising two resistors and two transistors, mounted on the SSB board near U3. This circuit provides effective control of an analog signal line with good noise immunity. The switchbox itself repurposes a computer COM port switch, using only two of its original connectors and four of the nine poles. It integrates a microphone preamplifier, a PTT circuit built with 'flying leads' construction, and RCA jacks for soundcard connections. A trimpot adjusts the audio drive to the K2. The central DB9 connector links to the K2's mic connector via a shielded RS232 serial cable, ensuring proper grounding and signal routing. An external footswitch PTT jack is also included. Further enhancements include a **noise-canceling microphone** preamp based on a QST December 2000 article, adapted for Heil mic elements. This preamp, built with pseudo-Manhattan style construction, provides a gain of approximately 2 by changing emitter resistors (R9 and R16) from 680 ohms to 330 ohms. A 10-ohm series resistor and 47 µF capacitor on the +5V supply mitigate noise spikes.

A site dedicated for the AM Radio Amateur and vintage radio. Home of the AM Press/Exchange, The AM Forum (the largest BBS of it's kind),and The AM Classifieds, Photos, Audio, and technical information. Audio and Video chat rooms.

This page documents Amateur Radio data digipeated by the International Space Station

The grounded half loop describe in this article is basically a half wave length wire on 80 Meters. The 80M grounded half loop antenna, inspired by a 1984 QST article by SM0AQW, is a compact solution for limited spaces. Comprising a 127-foot wire fed against ground and supported by radials, it balances performance and practicality. Despite compromises in length and proximity to structures, the antenna delivers strong signal reports and effective multi-band tuning using an SGC 237 antenna coupler. Ideal for CW operation, it offers low SWR on 80-10M, though noise levels and safety considerations warrant attention. This versatile design excels in constrained environments.

A home made antenna tuner based on the W6JJZ basic concept that ,atches balanced loads without the use of lossy baluns, can provide band-pass filtering and harmonic attenuation.

Amateur Television activities in Pittsburgh,ATV operators and users, ATV links, ATV information

XLS file with technical specifications about ham radio transceivers

tkD7 is an expectk script for controlling the Kenwood TH-D7 HT on Linux or FreeBSD

Eham users reviews of the hustler 5 btv HF vertical antenna

Complete introduction to Shortwave radio, includes Qsl gallery, Propagation, Beacons, Contest, Begginers guide, in Spanish

BQ9P Interactive Logbook 1998 DXpedition to Pratas Island

Converting a PC Switching Power Supply to 13.5V by AA3SJ

Delta 160-meter receiving antenna used at FO0AAA

Article about small magnetic loop antennas with notes on realization of magnetic loops for several HF bands and the six meter band

Benefits in implementing a remote antenna switching system and a sample remote antenna switch project

Magnetic loop for 20 to 6 metres pedestrian mobile by VK3YE

The Internet's most up-to-date list of UK radio stations simultaneously broadcasting on the web.

Operating on the 11-meter band, the Alfa Tango Argentina website serves as a digital hub for CB radio DX enthusiasts, particularly those affiliated with the _Alfa Tango_ international group. The resource primarily functions as a community portal, facilitating connections among members and promoting activities related to long-distance CB communications. It presents basic information about the group's presence in Argentina and emphasizes the social aspect of radio communication, framing participants as "friends who have never met." The site's content reflects the operational focus on **DXing** within the CB radio sphere, a practice that mirrors amateur radio's pursuit of distant contacts. While specific operational data or technical guides are not detailed, the site's existence supports the organizational structure of the Alfa Tango group, which coordinates activities across various countries.

CQ Serenade was composed sometime between 1965 and 1970 by Maurice Durieux, VE2QS.

The Baja Net is one of the boaters favorite nets on the West Coast. It has a long history of handling traffic for mariners who are out of touch with friends and family. Several stations have phone patches enabling them to put you right on the line to talk to your loved ones.

This calculator is designed to give the horizontal length of a particular dipole including Tees, antenna, or one side of it, for the frequency chosen. Enter the desired frequency and select the desired calculation from the drop box

Information about our local Echolink Node #1224, on Long Island NY

APRS activity in Ohio

Info and specifications on my three beacons on 10 and 6 meter bands. You will find also informations on the propagation for these two band.

Eham.net review of ICOM IC-2720H

This page describes an cheap RF signal source, a portable micro beacon, using a low cost temperature controlled crystal oscillator

A monster magnetic loop antenna for 160 meters band. This Magnetic loop is optimized for 1840 Khz + 50 Khz. PDF Article published on La Radiospecola 10.22

Radio repeater

Web pages of TRAC istanbul city branch

Free Logbook conversion program that allows the conversion of some old DBF log files (DXLog, EasyLog, LogPlus, TopLog, TurboLog TotalHAM92) to the ADIF Format, 3.8Mb ZipFile

Fill out the form to design a bandpass filter as described in the January 1985 issue of Ham Radio Magazine. These filters are generally limited to frequencies above 200 MHZ because their size is slightly longer than 1/4 wavelength

Transmission Line equations for Windows. Written in Visual C++. This program provides the most comprehensive analysis of a transmission line by w9dmk

This project hereby presented is a complete HAM radio simplex 'smart' repeater, built around a Motorola GM-350/950, Arduino NANO board and a WINBOND audio recording integrated circuit

Open-Source Software Implementation of a DRM (Digital Radio Mondiale) Receiver. Dream runs on virtually any pc and requires a receiver front-end to work as a real radio.