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在整个SCPC地球站设备中,与其它部分相比,上、下变频器出故障的概率相对比较高.由于上、下变频器工作频率高,结构复杂紧凑,工艺要求高,给设备的维修带来了一定的困难.同时上、下变频器的维修往往需要一些专门的仪器,而这些专门仪器在一些地球站还不具备.基于这一点,本讲所涉及的维修,只能是初步的.有些故障可以通过调试或者简单修理现场解决,有些则可以用现场替换的方法解决,还有一些只能是判断出故障所在的模块后送到专门的维修中心或工厂修理.为了提高变频设备的可靠性,上、下变频器由主用和备用设备组成,并配有自动倒换装置.必要时,也可以工作在“强制手动”状态.上、下变频器是SCPC数字卫星地球站设备的重要组成部分,它主要完成下面两个功能:(1)将70MHz±18MHz中频已调信号经过两次上变频,变换成上行的射频信号,以便信号能在卫星信道上传输.通过改变上变频器中的发送频率合成器的频率,就可使发射频率选择在系统所指定的卫星转发器上.
In the entire SCPC earth station equipment, compared with other parts, up and down the probability of failure of the inverter is relatively high.As the upper and lower frequency converter high frequency, complex structure, high technology requirements, to the equipment maintenance zone Come to a certain difficulty.At the same time, up and down converter repair often need some specialized instruments, and these special instruments in some earth stations do not have .Based on this, this talk about the maintenance, can only be preliminary. Some faults can be debugged or simply repaired on-site to solve some of them can be replaced with on-site solution, and some can only determine the module where the fault is sent to a dedicated repair center or factory repair.In order to improve the reliability of inverter equipment The upper and lower frequency inverters are composed of main and backup devices and are equipped with automatic switching devices and can also work in “forced manual” mode if necessary.Up and downconverters are an important component of the SCPC digital satellite earth station equipment Part, it mainly completes the following two functions: (1) The 70MHz ± 18MHz intermediate frequency modulated signal is upconverted twice, converted into uplink RF signal, so that the signal can be in the satellite letter Transmission by changing the frequency of the inverter in the transmission frequency synthesizer, the transmit frequency can be selected so that the system specified on the satellite transponder.