[subhumanderelict]

Originally Posted by bakntyme

WARNING: boring technical info below
If you want to try the external antenna anyway, antennas are tuned by adjusting the length of the antenna; it should be an integral multiple of half of the desired wavelength. The wavelength is the speed of radio waves, which is the speed of light, divided by the frequency; so a frequency of 1900 MHz would have a wavelength of approximately 0.15789 meters, or approximately 6.216 inches. Therefore, an antenna of a length that is a multiple of 3.108 inches would provide the best signal.

See Wavelength and Frequency, Univ. of Oregon

You're right; this would be worth a shot too. For high frequencies, it's mostly dependant on the dimensions of the antenna. I just hope the OP doesn't mind if this thing doesn't work after this, in case something goes wrong.