Some of these PMR sets have detachable antennas or external antenna output. By using an external antenna the range would be greatly improved. I've seen such with small magnet-based ones for use with cellular phones. I'm not sure there is some available for the PMR range (400Mhz or so), but I would bet a coin or two that the 900 versions would improve greatly compared to using the radio inside the car.
However, I do not know if external antennas is legal in this application in your country.
Regards, Tore |