by KK6EK

DXA displays near-real-time information from an amateur radio DXpedition. It was developed as an aid to DXers wishing to work the DXpedition, and as a tool of general interest. It makes use of a source computer, a satellite data link, and a website with dynamic content. The system enables the remote site to update the information on the website, which is then able to serve dynamic content to clients using an ordinary web browser. No software is required to use DXA; it works in any web browser.

If you are a radio amateur interested in working the DXpedition, you will find the information on DXA very helpful. The DXA window automatically updates itself approximately once per minute. Provision is made for you to log into DXA using your callsign. While this is not required, it enables you to obtain current information about your status in the DXpedition radio log.

DXA was written by Robert W. Schmieder, KK6EK, with the advice and consultation of many DXers. Its initial use was for the 2005 Kure Atoll DXpedition K7C, and the instructions below were written for the K7C DXpedition. Currently (Nov. 2011) it is being re-written to be useful for any DXpedition; it will be used next on the 2012 Clipperton Island DXpedition TX5Q. You may use DXA freely and openly, but you may not download the site or use its contents without permission from the copyright owner. Please see the DISCLAIMER comments below. We would welcome your comments about DXA; please send them to


The first step you should do is LOG IN. Use your own callsign but do not use a suffix such as /K7. Logging in enables you to see your personal records in the DXpedition log. Each time you launch a new browser, you must log in again.
This is your personal bandmode table. It shows which bandmodes have been logged by the DXpedition for the entered callsign (here W1AW). After you make a QSO, watch this table. Within a few minutes, a green square should light up, indicating that you are safely in the log. If is does, you can be sure of getting a QSL confirmation of this QSO. If it does not, you should consider making another QSO with the DXpedition.

The display area. In this area, various content can be displayed by using the navigation bar:

MAINVIEW reloads the entire DXA window, and resets the displays to their default and current values.

Callsigns are displayed on the azimuthal-equidistant map of the world. Some callsigns may be obscured. The callsigns on the map correspond to those in the LAST MINUTE list (see below). The position of the callsign is approximate.
The PROP'G'N area. See this by clicking on the link:

Propagation ellipses are superimposed on the MAINVIEW map. These ellipses show the predicted strongest signals from K7C. The signal strength is color-coded:


Clicking on the bands indicated in the line at top will bring up the ellipses for that band. These ellipses are calculated to within the hour.

NOTE: This plot does not imply that the callsigns shown were logged on the band shown.

We thank Dean Straw N6BV for these calculations.

The LAST MINUTE list shows the callsigns added to the DXpedition log in the last minute. This display will be updated a few minutes after the QSO is logged by the DXpedition.

The LAST HOUR list shows the callsigns added to the DXpedition log in the last hour (including the last minute at the top of the list).

Depending on the version of DXA, these columns mightbe labeled LAST 10, LAST 100, PREV 100, etc.

Special messages from the DXpedition.
These will be sent at irregular times. You are encouraged to watch for messages that are directed at you personally. If you see such a message, it might contain an instruction to respond. However,


Various CONTENT can be displayed by clicking on the respective navigation link.

IMAGES from the DXpedition will be uploaded in batches at unpredictable times.
AUDIO clips. New clips may be added during the DXpedition. You are invited to contribute your audio clips. They must be less than 30 s duration and of mp3 format only. Send to e-mail DXA.
The DXpedition site, showing DIRECTIONS to the major radio amateur populations of the world. Mouse over to get close-up; click to get position of the site in the world.
The SUNLIGHT on the world as an Azimuthal-Equidistant map (keyed to the hour), with Kure Atoll K7C at the center.
The WORLD as seen from space (keyed to the hour), with the DXpedition at the center.
Callsigns and locations of the RELAYStations. You can click on each callsign and send an e-mail to that station. You are encouraged to send comments and contributions such as audio clips. They must be 30 s or less, mp3 format only. Send to any station, or to e-mail DXA.

Your local time
UTC time
The bandmodes currently active at the DXpedition. The time elapsed since the start of the operation. The time remaining until the end of the operation. The total number of QSOs logged.

DXA displays current information about the DXpedition radio log and operations. However, DXA IS NOT THE LOG! In particular, DXA may fail to display valid log data or may display erroneous data. No QSLing will be done based on data supplied to, or displayed on, DXA. DXA is meant only to be an aid to the DXer, and a source of information and interest, and does not constitute the official record of the DXpedition. If you have any comments about DXA, please send them to e-mail DXA.
The concept of DXA was discussed early in 2003 with many well-known DXers, including NP4IW, N7CQQ, ON4UN, ON6TT, ON5NT, ON4WW, PA3DUU, PA5EA, LA9HE, HB9AHL, HB9AFI, HB9BHW, HB9BCK, OE9AHJ, and DJ9ZB. Most of the K7C team, including NI6T, AD6E, NØAX, W6KK, VE7CT, K6SGH, K6SRZ, N6HC, N7CQQ, WA1S, DJ9ZB, and DJ5IW have contributed ideas and criticism. For the initial deployment on K7C, we thank N6BV for contributing the propagation prediction data used on this site, Doug Jensen for critical technical help just before launch, and K6SGH for extensive technical assistance and proofing, and for keeping DXA running during the difficult operations on K7C. DXA version 2 is being developed by KK6EK, W6OP, N7XG, and AD6E.

Copyright © 2011 Robert W. Schmieder All rights reserved. Last update: Tuesday, March 08, 2011