direct talk

So, I was doing some reading and came upon some old threads that talked about Nextel Direct Talk (Not Direct Connect) where the phones have the ability to go off network and talk directly over the 900mhz ISM band frequencies. First off I had no idea that some of these iDen phones did that, but...

I have some motorola i355 phones that i use for the off-network direct talk feature. I know that motorola makes a factory extended antenna for this phone but im looking for some better antennas that i can get even more range on. I also know of the Yagi antenna and the Omni antenna but these are...