| 摘要 |
PURPOSE:To always enjoy satellite broadcasting under the optimum condition, by comparing a receiving level detecting value with a value stored in a memory and generating an alarm informing the necessity of antenna direction adjustment when the difference between the two values exceeds a fixed value. CONSTITUTION:When the maximum value VMAX of receiving signal level obtained during antenna adjustment is larger than the peak value VBST till then, the peak value VBST stored in an ROM 34 is replaced with the maximum value VMAX. When it is discriminated that broadcasting is on the air, the maximum value of the receiving level till then is read out from the ROM 34 and the tuning is fixed to the channel of the broadcasting. Then the receiving signal level is detected from the channel and calibrated by using an offset value. The difference between the calibrated value VLVL and maximum value VST is detected and, when the difference is larger than a prescribed value, it is discriminated that the antenna direction is out of position and an error message is displayed on the screen of a monitor receiver 38. At the same time, alarming sounds are produced. |
