YBX-1收发信机取消过载过压保护的探讨

通过对取消线路线滤（以下简称线滤）插件中压敏电阻等元件前后，高频保护缺陷的统计比较和线滤电路原理分析，发现取消压敏电阻后，线滤电容击穿缺陷显著增加，原因是雷击引起的高频干扰高频通串入收发信机，幅值高的干扰信号直接经过变压器加在滤波电容上，造成电容击穿。另外，近外故障或开关刀闸操作，也会在高频电缆中产生浪涌电压，进入收发信机，造成滤波电容击穿。根据分析指出目前应考虑恢复装设压敏电阻，同时提高应通过全面提高装置抗干扰设计等级和元件质量，稳妥地执行YBX-1收发信机取消线滤过载过压保护措施。

Study on revoking overload and overvoltage protection of YBX-1

By statistic comparison of HF protection defects and principle analysis, it shows that the capacitor breakup defects increase obviously after removing the pressure sensitive resistance from the linear filter. It is because the HF interference caused by the lightning rushes into YBX?1 via HF channel and the strong interference signal goes directly on filter capacitor through transformer. Furthermore, the nearby switch operation or fault may also cause inrush voltage in HF cable resulting in the same defects. It is pointed out that the pressure sensitive resistance should be restored at present time and the revoking of YBX?1's overload and overvoltage protection should be carefully carried out by improving the anti interference design and component quality.