Multiple GPS for ultras (Read 815 times)

Even if the battery lasts 12 hours, the Forerunner doesn't have enough memory to store every bit of detail.  The truncation of data starts at around 4 hours, I believe.

I'm not sure how correct this is, but I know that all my HR, pace, and GPS data were fine for all my runs, irrespective of length. 

• battery life, my FR305 lasts for about 8 hours
  If you want to make life longer maybe try some USB loader which can load from batteries. Not a nice solution because you have to run/bike with the craddle, a couple of batteries, and the loader. But it is cheaper than buy a second 305 or a new 310.
• # of laps, i've read there is a 1000 laps bug which stops the FR305 from recording, so check first the number of laps on the watch;
• memory full, offcourse time when happens depends on the recording mode and the recorded data. For long distance use smart recording instead of 1 second recording and switch your foodpot/cadence unit off.
  At 1 second it can record for about 3,5 hours according to the manual. Infact it can record more, but the last hours of your activity will be present as it overwrites the older data.
  The exact time for your watch is easily found by set it on 1 second, have a gps fix, place it in your garden or so hit the startbutton and let it there for 4 or more hours and press stop, hold the lapbutton and upload the "activity". If you can see in detail by looking in the tcx file, you can figure out for how long it records detailled data. I once did a test, and for what i remember it is about 3h45min. It also gives you a hint about the number of datapoints after when the memory is full.
  So although smart recording is "smart" it also records datapoints at a certain number of seconds so if you can figure out the time factor you almost know in front when your watch has a full memory.
  If you run near/into a full memory, you can try to save the activity to a course after first press stop and reset. Never done this, but it should save at least the GPS info. Then start a new activity. As far as i know memory for courses and history are separated, but both are limited. I don't know the size as i never have to use it. The new activity will delete detailled data from the older activity. In this case that is the one you just saved as a course. So at the end you have one course and one activity which both can be uploaded to garmin training center. At least the course file has to be converted to tcx to upload it here. Also never done that part of the story so maybe Eric has made some fancy upload thing which also can upload courses.

And...

succes with the 100 miler

I believe that some of the newer Garmins have a better battery life. The 310XT is supposed to last for around 20 hours. I haven't tried it though.

yes, this was mentioned in the original post.  Mine lasts about 15ish hours.

Would a solar USB charger work?

http://www.google.com/products/catalog?hl=en&source=hp&q=solar+usb+charger&um=1&ie=UTF-8&cid=8658963470713032238&ei=HmxCS__fGtKXtgesjrGTCQ&sa=X&oi=product_catalog_result&ct=result&resnum=1&ved=0CBEQ8wIwAA#ps-sellers

 

My 405 started "low battery" around 6.5 hrs (abt as I finished).

Mine craps out at about 6.5 too.