General Techniques MLat stopped working Network test functions

There is a self-test URL here: http://www.coaa.co.uk/gs-mu-test.php, and a self-help group for Mlat setup here: http://groups.yahoo.com/group/planeplotter-mlat/

General Techniques

It may help in diagnosing problems when trying to perform Mlat requests, to recognise the various possible symptoms of failure and their probable causes.

When you Ctrl-left click on a 'position-less' aircraft in the View..Aircraft screen, several things might happen.

The aircraft on which you clicked, will become the designated aircraft and will turn red on the View..Aircraft screen.

In the title bar, you may immediately see a message like one of the following:

• "No recent data for selected aircraft" - self explanatory.  Choose a different aircraft that is currently being tracked. 
• "Insufficient raw data sharers" - self explanatory.  Choose a different aircraft that is being received by several active Ground Stations (GS).  Are you sharing?  If not, there will be no GSs in your list. 
• "Sharing state incompatible with Mlat request" - self explanatory.  You are sharing in the upload-only mode and therefore cannot elicit the data from the sharing system.  Change the sharing mode (to two diagonal arrows) and try again.

If no such messages appear in the title bar, the program will try to initiate an Mlat request.

• A pop up box will appear saying "Sending request".  In a second or so it should change to a countdown "Time remaining".  If the "Sending request" message persists for any length of time, then there is a problem accessing the Internet.  Check the permissions for PlanePlotter in your firewall.
• At this point you might see a red alert box with the message "Multilat is not enabled".  In that case, you are not currently entitled to make an Mlat request.  You can either be validated as a Ground Station (providing raw data to other users) or you can request Master User status on a trial basis by visiting http://www.coaa.co.uk/mlat_request.php. 
• If you see no red alert message and the pop up box simply shows the "Time remaining" message, the Mlat request has been accepted and you can be confident that you do indeed have Master User status. 
• At the end of the minute during which incoming data is accumulated, you should see significant numbers in the various fields and, if there are sufficient hyper curves, the program will switch to the chart view and display the calculated position for your chosen target. 
• If you get only a small number of responses, you may have chosen an aircraft that is not well covered, or your firewall may be blocking the incoming packets because it interprets the data stream as a Denial of Service (DoS) attack.  Try other aircraft but if the number is always too few, adjust your firewall DoS settings. 
• If you persistently get zero results at the end of the minute, then the incoming raw data is not reaching Plane Plotter at all.  Check your router port forwarding settings to make sure that the correct format (UDP), the correct port (9742) and the correct IP address (the machine running Plane Plotter) have been entered.

This is from a post on the Plane Plotter Yahoo group by Bev (Plane Plotter author):

  http://groups.yahoo.com/group/planeplotter/message/21174

MLat stopped working

Q: I was running MLat for a period of time OK, but when I rebooted after a day or two I can start requests but I get nothing back.

A: Check that the IP address of your computer and the forwarding address specified in your router still match.  You may want to make the lease period much longer on your router (say 28 days, see your router for details), or move to using fixed computer IPs - a static IP address.  For some more information - see: http://portforward.com/networking/staticip.htm

Q: If you plug the SBS to a different USB port after removing the SBS-1 connection, Windows Vista might overwrite the DLL files patched by the Vodka patch.
A: Always use the same USB port once you are set up.  If required, re-install the patch, making careful note of where the DLLs are located.

Network test functions

From version 5.4.6 (upgrade here) Plane Plotter includes a series of Networking Test functions under the Help menu.  You will find these most helpful in checking out your system prior to applying for Ground Station or Master User status.