A display device for a telescope system is disposed between a first image plane and a second image plane of the telescope system. A communications service includes a caller ID configuration function. The system analyzes various parameters of the received signal by taking instantaneous measurements of data points in moving window and thereby determining whether the signal is of poor quality. An amount of correction movement \u03b4x for canceling the movement in the X-axis direction caused by the rotation \u0394\u03b8 of the pivot axis B is calculated. The first mounting structure includes an installation member, and a locking member slidably installed in the installation member. In this way, an enhanced TCP device that receives the RST packet can access the RST reason code in machine-readable form and, unlike prior art implementations in which ASCII text is carried in the TCP payload to provide a RST reason, without having to process the payload of the TCP packet.