single satellite radio antenna to a dual antenna adaptor?

[todd1010]

Where were you guys purchasing the single to dual antenna adaptor to use the newer satellite boxes with older dual antenna leads?

[eddier]

I just ran the sat signal to the unit and my reception is fine...not sure if it is either

1) ignoring the terr signal or
2) joining the signals at the receiver level like some of the old units used it.

for more info, i have avic-z3 w/ XM and i used my OEM XM sharkfin antenna wires found in the trunk.

[todd1010]

having a dual antenna and then using a single antenna tuner box, will it decrease my reception?