I have a Huawei B316 modem in my motorhome that I use with either Wireless Nation data or Spark prepay depending which card and APN I have in use at the time. I have picked up a Laird antenna - 4G/3G Multiband Phantom® Antenna 698-960 MHz/1700-2700 MHz which I have connected to one of the external aerial ports. Would there be any advantage in fitting a second external antenna and if so would I need to put the two antennas at 90 degrees to one another?  Any advice much appreciated. I have been using the aerial internally at this stage but once I finalise what I am doing I will mount it externally on the edge of the roof.

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