LED handlamp

Not exactly a recent project but decided to post it anyway.

It's essentially an array of 45 high-output LEDs, current limited with resistors and on/off by a simple switch.

As simple as it can get.

 

 On addition to this veroboard schematic is the battery composed of 8 AA/R6 batteries and the little switch.

Oh and .. It's effing bright.

Air-ram, PC cooling.

So this is another need-to-do-something-but-what project.
My GPU(GTX260) got problems with heating, even on 100% fan speed it'll still go way above 80c.
It's just not pleasant when gaming...
So what if I use the cold Swedish weather to cool down the ambient air in the case hence increase cooling power of my GPU fan?

A lot of cardboard, glue and ducttape later...

There's a 120mm/12V fan in the duct sucking air in from outdoors.
The duct gets divided in 2(up/down section) after the first fan and then hits the case fans which increases pressure further.
Originally I ran the ductfan from an AC-DC converter with an output of 13VDC, using around 400mA.
End results for this version was pretty decent, knocked my temperatures down by a lot but also made a lot of noise by operating at ~108% of rated voltage all the time..



I have since the first version improved it a little bit by adding some control to the fan, with the push of a button it'll run at higher RPM's for a set amount of time.

The fan now works between around 9V and 16V, which means in default mode it'll run at 75% of it's capacity and in boost mode it'll run for around 2 minutes at 133% of capacity.
Boost mode is probably bad for it's lifelength but seeing as this is a quick mock-up I don't care too much about it.