Well, seeing as how we're only 3 days away from the shortest day down here, my 10km each way bicycle commute is spending a lot of time in the dark.
Battery-powered lights and rechargeable batteries are cheap and effective, but 2 things about them get my goat: having to use 3 switches to turn the system on (headlight & front/rear LED flashers), and having to dismantle each light to recharge the batteries. Dynamo lights don't have those disadvantages, but they (or at least the inexpensive ones) don't work while you're stationary, say at a traffic light.
Anyhoo, to make along story short I've constucted a small box that contains 5 x AAA rechargeable batteries, and a simple charge control & LED flasher circuit.
The power input is supplied by a hub dynamo, which cost the outrageous sum of $10. I was able to dismantle a spare front wheel I had lying around, and by using a slightly different lacing pattern the spokes were the correct length. I've soldered a short length of cable with a DC power plug to the output terminals so that I can still remove the wheel to fix flats, or if the system needs a supplementary charge using a plugpack.
The control box bolts onto the mounting posts for the second water bottle, on the seat tube just above the pedals. Using AAA batteries provides 30 minutes worth of lighting without any further charging, and makes the whole unit quite unobtrusively small:
The box has a switch to let me select Off/Charge/Charge+Lights. It also has an LED to indicate when the batteries are fully charged.
Performance wise, I took it on its maiden voyage at 06:50 this morning. I'd given the batteries a half-charge the night before, and the lights died at the halfway point. After a bit of examination it turned out that one of the wires has come loose from the dynamo. I fixed that for the ride home, and after 30 minutes on the move the lights kept running for 5 minutes after the trip was over. With a bit of luck my battery recharging days are over (for bike lights, at least.)
BTH
