by switching on the debug on the INDI driver for the AstroTechTracker I have confirmed that this is not an issue!

basically my phd2 configuration set an option "Use Pulse Cmd" off and that suits the rather old version of the firmware I have for the AstroTechTracker. However when I start my rig with a different application for example the Cartes du Ciel ccdciel software that switched this option on. By looking at the driver debug I worked out that the two applications (phd2 and ccdciel) were attempting to use different guide mechanisms so I can now reconfigure both application to use the same mechanism and the original problem is solved.

phd2 saves the INDI properties with single quote and the other applications save the INDI properties with double quotes but both styles of configuration file work.

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