Apptech wrote:
>> My missus is having some problems seeing things on the 
>> road now that she
>> is riding her (motor) cycle home in the dark.
>> I was wondering how 2 of these things mounted beside the 
>> main light
>> would go in terms of enhancing the "near field" 
>> illumination something
>> in the order of 20-30 meters or so would be the upper 
>> limit of what I
>> was hoping for, this is in addition to her existing light.
>> Aimed fairly downwards so as not to get in the face of 
>> other drivers.
>>     
>
> Unlikely to be a cost effective solution. Biggest is 4 Watts 
> which is only maybe 20 Watts tungsten equivalent or 5-10W 
> halogen equivalent.
>   
My understanding was they had a 10W version, that was equivalent to 
around a 60-90W tungsten?
The other aspect is styling, she has a naked bike so something small is 
probably preferable, and i just happened to spot a location I could put 
2 of these.
> If it's legal where you are add some extra driving lights.
> If it's not legal move somewhere sensible :-).
>   
Given the number of bastards driving around the city with their 
headlights aimed at the sky I imagine she can get away with pretty much 
anything.
I was hoping these would do the job in terms of driving lights but in 
the smallest form factor possible, trying to keep it somewhat stock looking.
> Or perhaps try and play with the beam forming optics in her 
> present headlight.
>   
Not going to happen lol, this is her "daily/nightly driver" so 
modification of critical systems is not allowed, adding non-essential 
stuff is ok.
> In my motorcycling days I found that more light was usually 
> better. Much more light much better.
> Converting a 6V trail bike alternator system to 12V gave 
> enough Watts for a real headlight at the expense of less 
> light at low revs.
>   
I have tried to upgrade her headlight in the past to a 95/105W from its 
present 55/65W but i think the 95W rating on the replacement might well 
be "rice watts", I put a 95 in my car next to the 55w and i couldn't see 
that much of a difference.
I'll take a look at some of the mini driving light type halogens and see 
if she can be persuaded.

>
> ___________
>
> Use with an A123 torch is attractive.
> You'll need a boost converter with less than 4 cells.
> Ask if you get serious about that.
>   
Forward voltage is ~3-3.5 from what i can see of the data sheet.
A123 charged voltage is 3.6V, it wants some sort of buck/boost thing 
because your really pretty close as it stands.
> Note that a 2000 mAh cell has about 2 Watt hour capacity at 
> moderate load so at 4W load it will last << 1/2 an hour.
>   
under a 10W load (assuming you can hang on to the end of the thing).
A123 = 2.2Ah * 3.3V = ~7Wh
2A draw on an A123 isn't going to bother it that much.
So your looking at more like 45 minutes. Which is way more than I need.
I would put it in my current dinky little Al torch but the ID is like 1 
mm too small, oh well might be time to bust out some stainless and 
really go to town on it.

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