Well I am going to replace bulbs with LED that's already decided. I don't have the parts to just _do it_ though, I would need to figure = out what I need and order it. I checked white LEDs today, they are about $2-3 (USD) each. I figure using 3-4 would give enough light to be legal. I was thinking a supercap would be easier to use, I also read the = pulsing the light would be more efficient, in that case just a resistor = isn't going to do it.. About the dynamo, not sure really, it's one of those that "leans" on the = tire for rotation. I'm guessing that is friction, this hub thing, what is that? Any suggestions would be greatly appriciated, Patrik ----- Original Message -----=20 From: "Jinx" To: Sent: Tuesday, July 10, 2001 11:19 PM Subject: Re: [EE]: LED bicycle headlight > > Well currently I use a dynamo (this is a very old bike, 20-30 years > > or so) and it has filametn bulbs front and rear, what I would like = is > > a constanst light output no matter how fast I bike, which is not the > > case atm, and light when the bike isn't moving, in case you have > > to stop for traffic or something. One idea would be to have the > > light on for about a minute after the dynamo stops charging. >=20 > > I was browsing maxim earlier for those battery ICs, found a few, > > most were programmable by an SMB bus, I'd rather keep this > > as simple as possible >=20 > Patrik, the first decision you need to make is whether you stick > with filaments or change to LEDs. That will then help you decide > what back-up supply to use. If you stay with filaments, a supercap > won't do it (two bulbs could use 1500mA). Go to LEDs and you'll > find the current requirements drop dramatically to 20-30mA, which > could be supplied by a battery or supercap. I think this is really a > case of putting aside a Saturday and as Nike would say, just do > it ;-) BTW, are you using a hub or friction dynamo ? >=20 > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu >=20 >=20 -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu