Hi kg4wsv,
Thanks for the reply. According to the manufacturer's specs (USGlobalsat Inc.) power consumption of the GPS engine board (model EM-406a SiRF III) used in the Sparkfun GPS logger is 44mA. However, Sparkfun list it as 70mA (?). Sparkfun list the total power consumption on the GPS datalogger as 160mA, so I figured that the bulk of the difference was due to logger itself (I could be way off however).
You raise a really interesting idea with the notion of limiting the sentence output. We've discussed the idea here but our utter lack of electronics/programming knowledge meant it was a bit of a pipe dream. Many of the sentences are of little use to us and we really only need date, time, lat/long and HDOP values (possibly satellite number as well to help determine fix quality). Almost all of our projects require reasonably long deployment periods (from two weeks to many months), so fix logging intervals are usually set to between five minutes and one hour, with the unit being in sleep mode the rest of the time. Intermittent operation obviously boosts battery life/deployment (although we're finding some interesting results in terms of the benefits of longer intervals - - i.e. there doesn't seem to be many), but do you think reducing sentence output would have much of a positive impact? Would certainly make things easier when transferring data over at the end of deployment, regardless.
I am wondering how difficult it would be to interface the same GPS engine board above with an Arduino board to play around with sentence output etc? I realise this is all a bit ambitious for a newbie, but I am happy to jump in and try, particularly if there are other people interested.
Cheers