On a metal vehicle the best place to mount an antenna is the middle of the roof.
However, for reasons which escape me, some people don't wish to drill a hole in the roof of their $120,000 vehicle!? :)
The next best place is somewhere with a decent amount of metal directly underneath it - this acts as a "ground plane" and will improve Tx and Rx. Bull bars, mirror brackets (trucks) are really poor places to put an antenna.
As you have gone to the expense of the Cel Fi thingie it's probably worth paying a professional to install an antenna as at cellular frequencies something like a poorly crimped connector can lose half your signal.
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"I beseech you in the bowels of Christ think it possible you may be mistaken"
Oliver Cromwell, 3rd August 1650 - in a letter to the General Assembly of the Kirk of Scotland
Thanks Mike. Will definitely get a professional install.
Hi Rob. This is my setup, and it works brilliantly. As you suggest, the aerial easily folds down if desired although I leave mine up full time. Gets tangled up in the occasional drive-through bottle shop but no big deal. Top of aerial is about 3500mm above ground, and I have a wire to another booster in the van. Cheers
Looks like the go. Though my roof height is already about 3.3 m. So needs to be folding!
Hi Rob. Folds down easily as just under the GME label is the hinge, with the release button just under that. Bit of a PITA releasing it way above head height, but in my case I simply stand on the running board of the car. Cheers