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.

Coilgun - v2b V: Coilgun vs 1.2mm Steel

Just some test shooting at a 1.2mm steel/iron plate, took 5 shots to get through.

 Metal sheet got more and more bent until the projectile finally managed to penetrate fully. Tip of projectile is quite damaged and more blunt than pointy now...

Coilgun - V2b IV

Since my last post here I've gotten the V2b to work, break and work again!

Results are very promising, easily shoots through 2x3mm plywood and I doubt the second stage is tuned anywhere near good.

So here's the setup.
From left to right: Cap charger(230VAC -> 325VDC), Capbank 1&2, Coilgun.
Also featured in the photo is a complete mess of wires.

 

Target holder:

Little video of the shots I've taken so far.

Coilgun - V2b III

Finally did something with this project
Capacitors should now be super-easy to hook up properly.
Charge and discharge wires properly set up and all.

Seperate positive poles and common ground.

I still need to:
-Hook up a battery for the trigger and lm311 circuit
-Get a better camera(Ugh, yes, I really do need one)
-Stuff.(I bet there's something really useful and critical behind this very useless line.)

Coilgun - V2b II

Another little update...

I've connected the capacitors, soldered coils to thyristor circuits and mounted everything on the 'prototype'.
-Grinded one projectile to match the barrel within ~0.3mm diameter
-Optogate is fitted, might still need to cover the holes and barrel a bit better so ambient light doesn't get through.
-**ck the control panel, I'll just put a trigger to fire the first stage and the rest is automatic.
-Everything besides 1st stage trigger and battery is soldered.
-Mounted protoboards with a little slab of glue(Hopefully removeable if need be)

Need to:
-Connect capacitors in a better way and make sure charge wires gets attached along with the charge equalizer.
-Hook up a battery for the trigger and lm311 circuit
-Get a better camera
-Stuff.

Coilgun - V2b

Just a tiny update on the 2stage/~400J coilgun.

I've found a suitable barrel, 6 meters of it to be precise, and the coils are now done as far as winding goes.

What's left to do is:
-Grind the bullets down to fit the barrel
-Make holes for and mount the optogate
-Solder all the circuits together
-Wire up what's left without electrocuting myself in the progress
-Make some kind of controlpanel for this

Nightlight

Microproject this time, still waiting for a good projectile tube for the coilgun..

Either way, I got annoyed with not being able to see my analog clock at night and instead of choosing a sensible solution I decided to have a LED light it up.
At the same time that I have this low-current LED as light I don't want it to waste battery power by being on 24/7 so it needed some kind of on/off circuit.

First few ideas were based around the clock itself, to have it as a timer and manually set when to light and not, I quickly deemed this as unnecessarily complex for such a small project.

This lead me to the next, final, idea: Light control.
I'm using a phototransistor to 'measure' the light and then decide if the LED should be lit or not. The circuit got a draw of ~3mA(As far as I can measure with my budget multimeters) when lit and in the µA range when not lit, this should give quite a good battery life even on AAA batteries.

The entire circuit consists of 5 resistors, 2 transistors and a phototransistor and has so far been tested on breadboard and in Proteus. I'll solder this together whenever the mood strikes me.

Here's a schematic 'til I get it soldered together.

Coilgun, 2 stage, ~400J aka V2b

Time for my first 'real' 2 stage coilgun I guess. First stage will be switched manually with a microswitch+SCR whilst the second stage will have an optical trigger.

2x3300µF caps with max 350V, planning to charge them to ~315.

So far it's just a pile of shit since I'm still looking for a suitable barrel, unlike my older coilguns I'm downsizing the projectile this time. Planning to have 9-11mm diameter projectiles.

Here's a little clip of the pictured optical triggering circuit and one of the SCR assemblies being used on another coilgun, that one has a inner diameter of 14mm and a 12mm diameter projectile weighing in at around 40 grams.

 You can also check this clip out on my youtube:  Click me!

Welcome back...

With a renewed interest for electronics and the funding to back it up I've decided to relaunch this blog. Hopefully it'll give some people a good read and a good way for me to write down what I do.

I'll start this out with a totally electronics-unrelated project. A cellphone holder for my bicycle so I can watch the GPS/Tracker stats while biking.

Made mostly out of 2mm plywood, holds the phone quite snuggly so it won't fall out, just for safety I'll most likely use a rubberband around it to secure the phone.


'til next time...