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No Nitrogen available : TREC Mode

This is what happens in OBS when used in TREC mode (specified by OBS$\backslash$SET CAL TREC) and when you do a CAL command without the argument COLD. In this mode, the receiver temperature is used to determine the gain (conversion from counts to temperature) of the receiver.

With this method, the parameters which have to be specified are thus

plus a number of (semi) constant parameters ($T_{cab}$, site altitude, etc...). The elevation (and hence $Air\_mass$) is read by the control program, as are the frequencies of the signal and image bands. All other parameters are derived by the calibration procedure.

The weather parameters may be supplied by the meteo station, specified by the OBS$\backslash$SET AMBIENT AUTO command. If this automatic station does not work, you have to supply by hand $P_{amb}, T_{amb}$ and $Humidity$. This is done by the OBS$\backslash$SET AMBIENT P_amb T_amb Humidity command. The $Humidity$ is not used for the calibration, but by the drive program for the refraction correction to the telescope pointing.


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Next: No Nitrogen available : Up: Calibration mode: COLD, AUTO, Previous: Calibration mode: COLD, AUTO,   Contents
Gildas manager 2018-06-21