MrWizard wrote:
do you mean if the 'cable' is thinner than a pencil ? that 'cable' can cost you what ever gain the antenna has
yup, be careful of cable loss. RG 58 a common 50 ohm cable has a loss/100ft of 21db @ 1GHz, almost double at 2GHz. and that is the frequency range your using with a cell phone.
RG6 a decent 75ohm cable easily available is 6db/100ft @1GHz.
LMR a low loss 50 ohm cable is about 4db/100ft @ 1GHz. LMR400 is about 1/2" in diameter, close to semi rigid, and basically for permanent installation. you aren't going to roll it up and store it. And it's spendy.
Now granted, few of us are going to have a 100ft run, but 30-50ft isn't unexpected. with RG58 you'd have 7-10db, a noticeable loss.
cable loss could easily exceed antenna gain. Get the antenna up high, and only as far away from booster as needed to avoid feedback. In my case I use a omni (or if needed yagi) antenna on a pole, with the antenna about 6ft above the top of the trailer. I have the antenna about 10ft horizontal and 5ft vertical from the booster inside antenna with no feedback. cable run from the booster output to the antenna is only about 15ft.