Astro Tracking

When the radiometer system is equipped with an azimuth scanner, so that full sky scanning is possible, the instrument can run in astro-tracking mode by setting the scan mode to Astro Tracking. Furthermore, it is assumed that the azimuth direction has been adjusted (0.0 DEG corresponds to north) by using the Adjust Azimuth with 
In astro-tracking mode, the radiometer is tracking an astronomical object, like the sun, moon, planets or a fixed star (selectable from the Object combo-box), while measuring line-of-sight quantities as IWV, LWP, etc. The user should activate these products (IWV, LWP, Attenuation) in the MDF product list with identical integration time (typically one second).  If a fixed star is selected as object, the right ascension and declination (both in DEG) must be specified. For triggering of astro-tracking (start and stop), an additional trigger is available (beside the usual ones). When checking Trigger Start by Elevation, the trigger will be issued when the astronomical object has reached a minimum elevation angle as given in Lowest Elevation Angle to Start Scan. E.g. when the object is below the horizon, it makes no sense to track it and the measurement can be halted until the object passes a specified elevation angle. The same trigger mechanism is available for stopping the track (Trigger Stop by Elevation).