Well, the cards send power to the antenna - this allows the antenna to switch or more correctly to receive or send whatever signal is required to the cards. But without the cards - the antenna is essentially a dumb device, no worky. No power, no signal nada.
To measure it objectively - You would have to negate any transmitting source that may be in proximity, wifi, Bluetooth devices, mobile phones, portable phones, radio anything, monitors, tvs - any electrical device really
lol, bloody hard to do these days,
Edited by RobM - 7/4/13 at 1:28am