I have an older Montana and I cannot use my regular cable connection to a Sat antenna and receiver. My line also provides the rooftop cable and it has an amplifier in line.
The way to tell is hook up your receiver and then check for 12Volts on the outside line to the SAT antenna. If you have the 12V from the receiver it will probably work.
On mine I installed another port on the outside by the entertainment center for a tripod Sat antenna.
But I got tired of that and purchased a crankup roof Sat Antenna and installed new cabling to both TV's.
Not sure what you can do with the new ones but if you can't deliver the 12V to the external SAT antenna, it won't work.