ZL2AFP Gridmap for MEPT_JT

Introduction

ZL2AFP Gridmap is a very simple application which runs in conjunction with WSPR by Joe Taylor K1JT. WSPR sends and receives propagation probes, and logs the result in a file. The transmitted data consists of the callsign, location (LOCATOR) and transmitted power, and the log also includes reception information for the stations received.

ZL2AFP Gridmap uses the information in the WSPR log to plot the location of the stations received on a simple world map marked with grid squares. It will work with your own log file (by default), with archived logs, or with files recorded by others.

The grid map graphic was provided by JF5EMF. The icon we use was borrowed from WSPR by K1JT.

Stripper is an independent applet (not required by Gridmap), written by Murray ZL1BPU. It allows you to strip out references to your own station (including transmit log lines), so you can more easily perform analysis on the log files, for example with a spreadsheet. It also automatically changes the name of the resulting stripped log file, for archive purposes.

Download

Gridmap Archive (202kb)

Installation

Simply unzip the archive into the folder in which WSPR operates. It needs to be here in order to automatically find the current ALL_MEPT.TXT file. Then create a shortcut to the executable Gridmap.exe.

The little archiving accessory Stripper (STRIPPER.EXE) has a setup file STRIPPER.SET which contains two lines. In the first, you place your callsign (defines the lines to be stripped from the log), and in the second you can place an alternative path (drive, folder) in which to find ALL_MEPT.TXT and to place the archives. If you leave this second line blank, Stripper will work in the current folder.

Both programs are compatible with at least Windows™ 95, 98 and XP. With Windows Vista, you're on your own!

Operation

With or without WSPR running, simply execute Gridmap from the Windows shortcut. It will show you a map of the world, and after a while (after the start of the odd minute) will read the log and display the positions of all the stations in the log. These are shown as small red circles. If WSPR is running, any new spots will appear as they are received.

Once WSPR has been running for some time, the log file becomes rather large, and Gridmap may slow down. It will also of course be plotting the same stations over and over. Once the log file gets beyond 50k or so in size (say once/week), it would be a good idea to stop WSPR briefly, archive the log, delete it and start WSPR over again.

Stripper has been designed to simplify the archiving process. When you have stopped WSPR, go to the operating folder, and run STRIPPER.EXE. It will create a new archive of ALL_MEPT.TXT with an eight-digit date/time filename, such as '08041322.TXT'.

In creating the archive file, Stripper leaves out all reference to your own station, so deleting the transmitting log entries, and it also deletes blank lines, including those where the station was detected but not decoded. The ALL_MEPT.TXT log file is not affected. Once Stripper has run, delete ALL_MEPT.TXT and restart WSPR.

Using Gridmap

Once it is running and has plotted the stations, you can move the mouse around the map and read off the grid locators on the program banner. If you very accurately place the mouse cursor in the centre of a red circle, the program will find the station (or one of the stations) in the log which caused the location to be marked, and will display the callsign on the banner as well. It only displays the first station to be found for that locator. You need to be very accurate with mouse position, as each locator area is only 3x2 pixels, and the little red circles are about 200km or 400km diameter!

The program only reads the log at the start of the odd minute, in order not to collide with the use of the file by WSPR. Thus the map is refreshed only every two minutes, and there may be some delay (up to two minutes) in plotting the stations as the program starts. If no stations are plotted after several minutes, you either have no spots in the log, or the program cannot find the log file.

The map is a fixed size, and there is no zoom feature.

Menu

If you right-click on the map, a simple menu is presented.

Help

Brings up the help information (this file).

About

Pops up a small screen showing program information and credits.

Gridmap always/not on top

Controls the behaviour of the program window relative to others.

Toggle circle size

Switches the little red locator identifying circle between large (400km diameter) and small (200km diameter). The default size is small.

Filename to open

Gridmap.exe works by default with ALL_MEPT.TXT in the current folder. This menu item brings up a file open dialog which allows you to open ANY log file (in WSPR format) to be used for display. Thus you can run the program from another folder, read logs recorded by friends, or use archive files created by Stripper.

Quit Program

Does the same as clicking the little 'X' in the top right corner of the banner. I'm sure you'll understand this one!

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Copyright © C. Wassilieff and M. Greenman 2008. All rights reserved.