QTH-Locator-Applet Description

Definition.
Local interactiv Geographic Map.
Calculator Form.
Show result in external Maps.
Usage.

Definition

Radioamateurs use the grid-locator or QTH to describe a geographic location on the earth.

On the right pane you can see the QTH-Locator-Applet for Radioamateurs.

Features:

Entering and displaying a grid-locator using an interactive geographic map.
Calculation of distance and (antenna-)direction between two QTHs using a form.
Showing these Results in external maps on the web.

Local interactive Geographic Map

On the right side you can see the interactive local map.

While you are moving the mouse over the local map you will see the current mouse position as qth-locator and the distance to your location in the browser's statusline.

By mouse-clicking into the local map you set the "Other Location" field in the form.

If you drag the mouse, the drag-start will become the "Your Location" field and the drag-end (where you release the mouse button) sets "Other Location" of the form.

There are several different local geographic maps available.

Calculator Form

converting a QTH-locator to north latitude/east longitude and vice verse.
If you type a locator into the field "Locator" and press <enter> the fields "North" and "East" are calculated.

If you type a number into either field "North" or "East" and press <enter> the field "Locator" is calculated.

converting the old european QTH-locator to the current format.
If you type an old european locator into the field "Locator" and press <enter> the value will be converted to the new format.
(e.g. "EN74C" will be converted to "JO43IB")

to calculate the distance and the (antenna-)direction between two locations on the earth.
Just enter values for "Your Location" and for "Other Location" and press <enter>. Distance and direction will be displayed in the message area.

showing the locator in the interactive local geographic map
Every time you enter a location into the form, the location is shown in the map, too. "Your Location" appears in blue, "Other Location" in red.

Show result in external Maps

The controlpanel (between internal map and form) has an array of smart pushbuttons. These are hyperlinks to other external web-sites with interactiv geogrphic maps that will zoom in and show "Your Location" or "Other Location"

Each time you change the value of "Your Location" or "Other Location" the caption of the pushbuttons and their hyperlinks are changed, too.

Usage

I used SUNs JDK-1.0 to develop the QTH-Locator-Applet.

The applet was tested, with Microsoft Internet Explorer 3.0 , Netscape Navigator 2.02 32 Bit and SUNs AppletViewer 1.0.2 under windows 95.

I have no other browsers/operating systems to test the applet. :-(

You can coment on the applet, report errors, ... via email. If you like other internet-users to see your message use the reply form instead.