R52Hn with only one antenna

I want to use R52Hn card with only one antenna. Do i need 50ohm terminator, or can i leave 2nd MMCX free? Will card be ok?

Better to use always instead of leave the connector “open”

why ?

Its mandatory to leave all activated radios conected to a antena or with the 50ohm res.

but if i only use one chain?

I think its better for a good signal. Perhaps not necessary if you use 1 chain.. But its a very cheap thing dude!