Thursday, September 9, 2010

LM317 UPS power modules


I was surfing eBay this morning and ran across a lot of cheap Chinese LM317s- seems lots of people wanted to sell me 50 of them for around 15$ - I was thinking about what I could do with that many - realized that since we recently converted to Century Link for my phone - and i have lots of wireless -phones i could make a UPS - but then i also realized that all of the base stations had a little DC plug that gave them their power. As well as the ADSL modem, and the wireless router.  Who needs a 100dollar ups inverter when everything can be battery powered.

Looking next to me, I see the old lawn tractor battery i keep on a float charger. I could make little power modules with the 317's and hook all of the phones/router/modem  and then power them off the one battery - It has scads of power and would allow lots of hours of uninterrupted Internet surfing and phone when the power goes off in the spring like it does around here. - or at least until the laptops batteries go flat. Then we could all call mom - unless she has Vonage - she would like that....


The parts should cost under a dollar (less the plugs and wires) - Lets see... blank pcb - a sharpie, some etchant and ....