On Wed, 10 May 2017 11:05:04 -0500, DougC
wrote:
So I'm shopping around for ANY kind of headlights that take 4 x AA
batteries, and there is none. The best I can find is one that takes 3 x
AAA, but that doesn't put out anywhere near what the previous lights did.
There's a reason why you'll only find 2 or 3 AA batteries. While
LED's require roughly 3.5 to 4.0 volts to operate. Something like
this:
http://us.tdk-lambda.com/lp/images/2011-10-chart.png
This varies with LED type, color temp, bin, etc. You can barely do
that with 2 alkaline AA cells at a nominal 1.5v each. It's easy to do
with 3 AA cells. Actually, it can be done with 2 cells using a boost
inverter to increase the battery voltage, but few do it. I think (not
sure) that my Planet Bike 1 watt Blaze headlight does that. It runs
on 2 AA alkaline batteries.
https://www.amazon.com/Planet-Bike-Blaze-1-Watt-Headlight/dp/B0015R1NBW
It's no longer in production.
It's rated at 76 lumens. Roughly, todays LED's produce 75-80 lumens
per watt of power consumption when warm. So, a 1 watt LED will
produce about 75 lumens. Newer LED's are more efficient, but this is
sufficient for a rough estimate of output.
Incidentally, 3 AAA alkaline batteries have the same capacity as 2 AA
alkaline batteries:
https://en.wikipedia.org/wiki/AAA_battery
https://en.wikipedia.org/wiki/AA_battery
A AAA battery has about 1000 ma-hrs of capacity while a AA does about
2500 ma-hrs:
AAA 3 cells * 1000 ma-hr * 1.5v = 4.5 watt-hrs
AA 2 cells * 2500 ma-hr * 1.5v = 4.5 watt-hrs
I don't need a whole lot of light,
How many lumens would you estimate that you need?
http://www.planetbike.com/page/learn/lightfinder
Plus--on the LWB recumbent, the lights have to be mounted upside-down.
And the old Cateye lights were "waterproof", while almost all of these
new ones are just "water resistant", and I'd bet, not nearly so if
mounted upside down in the rain...
Look for IP ratings, not marketing buzzwords.
https://en.wikipedia.org/wiki/IP_Code
Hint: You don't want waterproof. If it were, any standing water on
the not so perfect seal would get sucked into the flashlight if the
temperature drops and the air inside the light produces a partial
vacuum.
So far the best candidate is the little 3-AAA flashlights with handlebar
mounts. They're round beams but have a spot-flood focusing lens at
least. Plus they all have high/low/flash modes now.
If you're not picky about beam pattern, you could probably get away
with an LED flashlight and a handlebar mount. Something like this:
https://www.walmart.com/ip/Schwinn-1W-Head-Light/19593671
For a battery, it takes either a single 24650 LiIon cell, a single
18650 LiIon cell with an adapter sleeve, or 3 AAA alkaline batteries
in an included holder.
Given your requirements, I'm not sure what to recommend. However, I
would strongly suggest that you reconsider your aversion to LiIon
batteries. For lighting of any type, they're far superior to
alkaline.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558