well, old thread... GPS draws up to 100 mA or more (units like Map76csx consume 2AA connected in series in less than 16 hrs). The values of current shown in solar panel specs are apparently for maximum or average output on sunny day. It will be zero when there is no sun.john allsop wrote:If you can run a GPS from your car cigarette lighter socket, using the GPS accessory connector, why can,t you run your GPS directly from a water proofed flexable solar cell mounted on your deck,
Charging the batteries, - yes, this I can understand. But again, - not much need to do this for a GPS, at least on those trips that most of us do. GPS doesn't have to be "on" at all times. With intermittent use 16 hrs is plenty - enough for 2 weeks or so. (And this is for VERY power-hungry units with tons of memory and with compass function always "on"). Units with non-expandable memory have 20-30% longer battery life (10% according to Garmin, but it's more like 30% less with constant use of those memory cards), and those without compass - longer yet.
Weather/news/music radio... 12-16 hrs of battery life for relatively big SW receiver like Sony 7600gr or Degen/Kaito 1103, size of a pocket-book, loud and with all the broadcasting bands, plus SSB. There are many places where such a gizmo becomes necessary, as VHF weather channels are not available. Again, 16-20 hrs is enough for more than a week. (With listening through the earphones it should be enough for 2 weeks).
Monitoring Ch16 is perhaps the only reason to carry a solar panel on deck (which monitoring, as it's been noted, is mandatory so far only in the USA, and not enforced, AFAIK).