Splitting antenna

I am using my FreeBSD box as my main ingress to my RV trailer.  We move 
around and sometimes use Ethernet, sometimes PPP directly on DSL and 
sometimes we connect to a local wifi hotspot.  To get the best connection I 
have mounted an external, multi-band antenna on the trailer and connect it 
to one of the antenna connections on the wifi card.

My question is, can I split the antenna connection and use both antenna 
connectors on the wifi card (or three if I have that kind of card) or will 
that mess up the connection.  I know that each connection is for a different 
band.  Different camp grounds use different bands and sometimes I need to 
switch the antenna to get a better Internet connection.  It would be nice if 
I could just have both of then connected to the external antenna.

Cheers.

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D'Arcy J.M. Cain <darcy@druid.net>         |  Democracy is three wolves
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