Farmers Market

We took a family trip to the Berkeley Farmers Market, where I again spent way too much money on food. The highlights were sugary baby carrots, ultra sweet japanese sweet potatoes, beautiful Swiss chard, perfect yukon gold potatoes, wild boar sausages, strawberries, purple asparagus, delicious oranges, and eggs from carefree and unionized chickens. Oh yeah, and really good himalayan food for lunch!



Later on, we headed up to the little farm in Tilden to show little ZZN the animals

megalamp, the return

Using the lessons I learned from Megalamp I, I designed and built MaxiLume Turbo Type R this weekend. The design is pretty similar to the original instructables design, but with a few key differences.

1)Log pot (http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=P3H8502-ND), Panasonic EVU-F2MFL3D53
2)Cree XR-E, Q5 bin from DealExtreme. These took *forever* to arrive. Next time, I will try ordering from Cutter in Oz.
3)Flashlight clicky switch from DealExtreme
4)Running LEDs at 1000mA instead of 500mA, since the spec says they can handle that kind of current
5)Only 3 LEDs used, wired in series, not series parallel
6)Buckpuck, pot and switch are all cleverly mounted on the headlamp harness.
7)Used fancy Arctic Silver thermal epoxy, and I actually bought a heat sink (which still ended up being a bit small)


The instructables design outputs an anemic ~200 lumens without the squishy 2.5X blue correction factor at 8 watts. MaxiLume Turbo Type R however outputs a testosterone laden ~660 lumens at 11 watts, (~500 lumens at 8 watts), so better than 2x the efficiency... and you can run it super hot if you want too!

I'm using the same 10 cell battery pack with Tenergy cells, so 12 Volts, 2600 mA. The three Crees drop the voltage 11.1 volts at 1000 mA, so 12 V is just about perfect for a buck driver. Using LED pro, I should get these ball park run times:

Current (mA)    Battery life (hours)     Lumens
1000                             2.3                    660 
800                               3.0                   540
600                               4.1                   450
400                               6.5                   330

lenses (l2 optics) at left, 1000mA buckpuck at the upper left, fancy epoxy lower left, old Petzl headlamp harness at right, heatsink (http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=345-1062-ND wakefield 628-65AB) middle top.

mounted LEDs


more or less finished: wide angle sub lenses on


Let there be light! Now all I need is one of those "Let there be light" T-shirts with Maxwell's equations, and I could give up all hope of escaping nerddom


Heres a closup of the head piece.


And here we are in a dark room. I have found that one of each of the three sub lenses make a nice compromise of wideness and spot. Note that there is no trickery here. ISO 200, f 4.5, 1/30 second exposure.... BRIGHT!