he means avoid antennas marked rp-sma (its a different connector)
I think he means something like these:
http://www.amazon.com/dp/B00KAOT4LM/ref=wl_mb_recs_5_title
(you would have one on the transmitter, and one on the receiver/screen leaving the other as a standard ariel)
The transmitter will come with a default ariel, but the circular polarised ones give better video range.