Thank to all of you guys !
Actually all your advises was right.
Related to current problem we found that connectors of antenna was quite wet.We cleaned and dried it and now all is Ok.
But any way we have a lot of problems with TCAS and I think I`ll ask you again in the future.
I don`t know why I`m working for my company.
My workload is too heavy but salary is too small .
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STAS