Re: [John Muir Trail] Re: solar chargers for GPS
- I cannot recommend the Brunton Solarroll 9
I paid half of what they sell it for, but still consider it a bust.
Unless you sit around for hours in the peak sunshine hours of the day,
it will not charge anything. Recharged batteries only last a fraction of
the hours a lithium AA lasts in my GPS, so much so that for the weight
of 4 rechargeable batteries, plus the charger, and the SolarRoll with
12V adapter, I can bring enough AA lithiums to power my GPS for weeks.
My Garmin 60csx runs about 18 hours with regular alkaline AA, 12 hours
on a rechargeable AA and 50 hours on a lithium AA that weighs less than
half of the two other types, so essentially 100 hours for the same
weight. You could charge any device that has a cigarette lighter adapter
with it, but you really don't want to carry all that junk with you.
But more importantly - don't bring the GPS at all if you think you will
need it to find the trail. A set of small maps will be all you'll need.
I bring the GPS to record tracks and to motivate my kids with all kinds
of distance and elevation milestones. Navigation is unimportant (even
though we do have the 24k topo maps in it - way too detailed to use
beyond 0.5 mile view. gotta bring paper maps anyway.
We went this year for three weeks on the trail with a GPS (Garmin Oregon 550) that needed daily a set of AA batteries. In our training hikes we first used a Solio, but that didn't work out for us, because we first needed to charge the Solio and then we needed to charge the AA batteries from the Solio via an adapter and little charger. It took too much time and was a hassle with all the different parts.
We then got the PowerFilm USB+AA charger. That worked perfectly for us. It charges directly into two AA batteries and allows also to charge devices via USB. When charging via USB it is important to understand that the rechargable AA batteries need to be in the charger and need to have a partial charge. So you won't be able to save the weight of the batteries (1.75 oz) and just bring the charger (4.9 oz), if you are charging via USB.
Good luck with your hike next year.
--- In firstname.lastname@example.org, "DAVID" <rachelanddave@...> wrote:
> I'm planning on doing the JMT next summer in 10 days. I'm a GPS junkie and usually carry my Garmin Forerunner 310xt with me (basically a GPS watch for a runner, not the super-GPS handhelds that most backpackers seem to use). It only holds about 20 hours charge so I figure I'll need to recharge it 4-5 times. I've seen some solar chargers on the market but I was wondering if anybody has any suggestions/experience regarding recharging while on the trail. Any other options beyond solar? Much appreciated.