I purchased a Gumstix Pre-Go PPP with SMA connector. On the product page, it states:
Logic levels are at 3.3V, and the board is powered by the 5V supply; however, by removing and replacing a jumper resistor, the board can be powered by a 3.3V source.
Which specific resistor is it that needs to be removed, and what are the specifications of the resistor that it needs to be replaced with, in order to power this GPS module with a 3.3 V source?