WSQCall

Introduction and Setup Information

Version 1.00 17/11/2017

Introduction

WSQ is a Weak Signal QSO mode for LF/MF. It uses Incremental Frequency Keying (IFK), making it moderately drift-proof and easy to tune. The specific technology, IFK+, was developed to eliminate inter-symbol interference, and significantly reduce the effects of carrier interference. WSQCall is the implementation of this technology with improved performance and the addition of selective calling.

The symbol rate of WSQ is very slow (by default about two seconds per tone), but each individual tone transmitted carries a surprising amount of information, resulting in a typing speed of better than 5WPM. No, it's not quite as sensitive as WSPR, but it does offer slick operation, a low error rate, and true QSO capability with no timing restrictions.

WSQ uses 33 tones, spaced 1.46484375 Hz apart, resulting in a signal bandwidth of 50 Hz, including the keying sidebands (bandwidth assessed according to ITU-R SM.1138). The modulation is constant amplitude, phase coherent MFSK, using IFK coding with 32 frequency differences. This means that each symbol carries enough information for all lower case letters to be expressed in just one symbol, which greatly enhances the speed. (Morse code requires on average about 10 symbols per letter). The ITU Designation of this mode is 50H4F1B.

This version of WSQ (WSQCall version 1) is also backward compatible with the older WSQ2 mode, which uses 1.953125 Hz spacing and a bandwidth of 66 Hz (ITU Designation 66H4F1B). Use of the older version is to be discouraged, as there are many important advantages to the new version.

WSQCall borrows quite a bit of functionality from FSQCall, including selective calling, automated responses, and the ability to log all stations received. It also has brand new features such as three fully adjustable notches, to deal with those irritating interfering carriers so common on LF and MF. WSQCall operates in 'chat mode', with an operation style familiar to those conversant with cellular phone or internet chat.

Installation


The PTT/CAT settings dialogue.

Software Compatibility

The Windows™ software is written in ANSI C, and is compatible with Win2000, WinXP and Win7. It may work with Vista on some computers. The program requires at least a 1GHz processor, SVGA display and a 16-bit sound card. One serial port (or USB equivalent) is required for PTT control. Memory requirements are minimal, and the program size is little more than 100kB. The program should run quite well on a low-spec 'netbook' type computer, and the program screen size will also fit on the netbook screen. Be warned that some cheaper notebook computers may have sound card speed accuracy compatability issues.

The program consists of just one file, and no changes are made to the computer's registry or anywhere else. To remove the program, simply delete the files made during installation. A setup file is generated when you first run the program.

Developers interested in writing software for this mode should contact ZL2AFP (zl2afp "at" xtra.co.nz) for source code and other details.


Copyright © Murray Greenman and Con Wassilieff 2013-2017. All rights reserved.