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The method to establish the pointing model of the 65-meter radio telescope of Shanghai Astronomical Observatory (TM65 m) is described. The single-point data are collected by means of “cross scan”, then, they are fitted with a model including both the Gaussian and nonlinear terms. It is also simulated and analyzed how the antenna beam is broadened in the scanning process because of the angular size of a source. And the orbit prediction of sources is used to improve the modelling efficiency. Finally, an eight-parameter pointing model is built after fitting all the collected single-point errors. It is verified that the model works well in the X band and other low-frequency bands, the pointing accuracy at the X band attains 12.36 arcsec.

At first, the receiving system of the Tianma 65m radio telescope (TM65m in brief) and its noise characteristics at the L, S, C, and X four frequency bands are described. Then, a few measuring methods of system noise temperature are discussed, and the major factors affecting the noise temperature measurement are analyzed, including the errors caused by the non-linearity, feed network insertion loss, mismatch, and so on. With the Y-factor method the noise temperature of the noise source calibrated in the laboratory is verified, indicating that its accuracy attains ∼0.2K. Finally, the system noise temperatures actually measured at the four frequency bands and an analysis on the result are given.