When it comes to mobile units keep in mind that nearly all mobile units need a 50ohm feed line between the unit and the antenna. Connecting an antenna directly to the mobile unit is never advisable due to the power output. As spd mentioned earlier, you are dealing with RF and EMF. This is and produces radiation. There are RF exposure limits and it is very important to adhere to those limits. Not doing so can result in immediate damage such as an RF burn, or cell damage which is not noticeable immediate but turns into cancer later down the road. Best to read up on those limits so you know what they are and can prevent future health issues.