Antenna-a/b settings for XR2 cards at Mikrotik OS 3.10

hi everybody,

I need to know what will be the perfect antenna settings for XR2 card in Mikrotik Router OS running on RB333 and OS version is 3.10 ?

Is it Antenna-a or Antenna-b ?

Please help

Regards,
Litu
Sylhet
Bangladesh

Default settings should be perfect.
You need to use default ant-a.

Thank you very much.