I'm getting ready for a backpacking trip that will have me out of civilization for a few days. I'd like to be able to keep in touch with home via cellphone and also have a radio in-case there's no service in my little-bit-o-wilderness.
Batteries run down and spare batteries are heavy. I'm carrying everything on my back and every little bit of weight adds up.
I'm thinking about building a solar trickle charger for my batteries. I'd need around 6 volts for everything. Cell charger puts out 6 (I just checked it) and radios have 4-1.5 V batteries.
Can I just set up a bank of photocells to the appropriate plug and plug in my cellphone. I'd add a diode so the cell can't discharge through the cells if I'm in the shade. Is it that simple?
If so, I might sew half a dozen solar cells on the top of my pack and just let things charge all day while I'm hiking so the batteries never run down.
I guess I'm making this more complicated than it probably is because I'm not sure what the cell phone's electronics do if they have a varying input voltage as I walk in shade, clouds move etc. I also don't know if I need a specific threshold current before charging can take place.
[This message has been edited by maintenanceguy (edited 04-30-2004).]