the icom ic-7200 is a very nice transceiver. but sometimes this transceiver is very fragile if you operate it very closely from another station as for a contest session for example.
this co-sitting problem can destroy one or two pin diodes situated on the rf board which is situated just beside the antenna connector. this is causing a very big attenuation of the rx signal and sometimes erratic output rf power control. the diodes items reference are d164 and d165, pin diodes 1sv308.
my suggestion is to replace them by any equivalent but "stronger" component. i have personally used 2 pin diodes from pmr transceiver recuperation.
be careful, the 1sv308 is the smallest smd component you can found , less than 1 millimeter !.
i do suggest using a very small pcb including a complete replacement of d164, d165, r163, c171, r164 with high quality discrete components.
i do that on my ic-7200 and the result is better characteristics in rx sensitivity and automatic power control (apc)in case of high swr.
google翻译如下
的ic -7200 -pin二极管故障导致接收灵敏度非常大的损失
国际博物馆协会的ic -7200是一个非常不错的收发器。但有时这种收发器是非常脆弱的，如果你从另一个操作，例如作为一站比赛会非常密切的合作。
这种合作坐在问题可以摧毁一个或两个引脚上的射频电路板它只是旁边的天线连接器位于位于二极管。这是造成了非常大的接收信号的衰减，有时不稳定的射频输出功率控制。二极管项目参考之用d164和d165，pin二极管1sv308。
我的建议是，以取代任何同等的，但“强大”的组成部分他们。我个人所使用的垂直磁记录收发休养2引脚二极管。
小心，1sv308是最小的smd元件，你可以发现小于1毫米，！。
我建议使用一个非常小的pcb包括d164，d165，r163，c171，完全替代分立元件，高品质的r164。
我在我的ic -7200，结果在接收灵敏度和自动功率控制在高驻波比案（apc）的更好的特性。
