I want to build a standalone wifi repeater -- powered by the sun. The problem is how much solar power and how big of a battery?net draw 4.5v @ 0.66A with loadnet draw 4.5v @ 0.60A no loadI'm assuming the best choice would be a 6v battery with a a couple diodes in series to induce ~.5v drop. Then, I need something to charge it -- I found 2v 6w solar chargers in the automotive section of Sears and 6v 2w solar chargers in the marine section of Dick's Sporting Goods.How many solar panels and what capacity batteries should I use? Is this the best method or should I use a voltage regulator and go with 2v batteries?I need this to be as cheap and simple as possible...
I do not know, but there is a house in Lafayette which was built with solar power. It was to have a solar system, so the contractor's first act was to put up a solar array on the property. It had battery backup, and was used to provide the electrical power during construction. during completion of the house the solar system was installed on the roof of the house.
You won't get very far with THAT lash-up. First of all.. WHY would you want to use diodes to drop the voltage.. they DRAW CURRENT and that is something you don't have to spare. That draw of (660 ma) comes out to just under 3 watts. You DO KNOW that you can get that 4.5 Volts by driving a NAIL into the THIRD CELL in a 6 Volt wet cell battery... right? and for what you are doing, you have more current available with a 6 volt battery than a 2 volt battery. Anyway, you could use two 6 Volt batteries and tap them at the 4.5 volt point then tie them in parallel, but you could still use the 6 volt solar panel to charge them. Trying to use an inverter is just an exercise in futility.. With TWO of the LARGEST DEEP CYCLE BATTERIES you can buy at AutoZone running in Parallel and being charged by solar panels.. if you hook a 75 watt inverter to them, they will go flat in about 4 hours of use during the night. This is not rocket science. Back when cars were changing over from 6 volts to 2 volts, I powered up more than one 6 volt car radio off a 2 volt battery... when you grow up as poor as I did.. you get inventive. I later used the same trick on the 24 volt electrical systems the Jeeps were using, to power up clandestine repeaters in places where no repeaters should have been. About 25 years ago I was living in the Denver area and built up a 0 watt 2 meter repeater on a split channel and took it up to Mt. Evans during the summer and hid it in a pile of rocks. I used tone control, so we were the only ones using it and, as I said, It was a split channel.. so it wasn't on a regular repeater channel. That thing was still running when I moved from the Denver area about 3 years later and for all I know, It's still up there on Mt. Evans (find the Brittlecone Pines and look towards that small peak about a mile to the west)
