vrijdag 27 december 2013

Ordered PCBs

Normally, one of my friends etches the PCBs I design, but there are limits on how small you can make traces on those (and i'm pretty sure he got sick of drilling hundreds of holes every time). So about a month ago I re-designed some of the PCBs to have them made in China, and they finally arrived today!


I chose the "10pcs 10x10cm" option at iteadstudio, and I really wanted to take full advantage of the 100 square centimeters per board, so I tried to make everything as small as possible, while still using through hole components. The first thing I really wanted to have were some boards for the atmega328 microcontrollers. The one I designed to be etches by my friend were okay, but had were some flaws / things that could be improved: 

The crystal didn't really fit, the voltage regulator heatsink blocked the reset button, I never actually used the reset button, it didn't have enough 5v en 0v pins available, it didn't have leds for the Tx and Rx pins, and it used some jumpers, since it was single sided.


It took a lot of time to get the new design small while still having all the extra's on it, but I managed to squeeze it all down to the point where I didn't have a single bit of unused space on the pcb. 

To get it this small, I dumped the reset button all together, replaced the 5mm LEDs for small rectangular LEDs, put as much as possible underneath the chip itself, and used a 3mm "Polar" LED for the Rx/Tx. This it an LED with two oppositely connected diodes in it, and I wired it so when Tx is high, and Rx is low, it lights red, and when Tx is low and Rx is high, it lights green. Two leds for the price of one!


Another chip I use a lot is the 74hc595 shift register, and while the original etchable design I made for them was fine, I liked to have a professionally made version aswell. (I did add some capacitors and screw holes in the new design, but didn't change anything else.)

Apart from the shift registers there are some transistor arrays on the PCB. I use these when driving led strips, like in the "light boxes" and the modded IKEA light, but you can also solder resistors in place of the transistor arrays for driving simple LEDs. Another nice feature of these prints is that by placing the headers, you can choose between grouping the outputs as 8 | 8 | 8 or 9 | 6 | 9. The lather is usefull when using RGB LEDs, because then you can simply use eight 3-pin connectors. 


At the edge of the 10x10cm PCB I had some space left, which I used to make some "led strip connector PCBs", just a small strip where you can solder pieces of led strip on to connect them together. This makes a nice 2.3W RGB LED.

After soldering one board of each kind I strapped them all together; they do their job like chinese factory workers!


The metal plate is from another IKEA light I'm modding, but it's still a work in progress...

donderdag 19 december 2013

3D Models

While I was working in a laminate flooring store, I made 3d-models to help them plan the expansion of one of their stores.


woensdag 18 december 2013

Amp

I finished my amplifier! I'm pretty sure this is the only recent thing I've built that doesn't have any leds.


maandag 9 december 2013

Thermometer

The winter is upon us again, so I made a thermometer, with, you might have guessed it, leds! Since I only need 4 pins for this project, (3 leds pins and 1 sensor pin), I used a small Attiny13 microcontroller. It was a bit tricky fitting all the code in there though, since there is only 1kbyte memory on those things, but I managed to get it working.

When it's 20C, the led is green. This slowly changes over to red at 25C, and blue at 15C


donderdag 28 november 2013

Led Cubes!

As someone loving leds, I obviously couldn't nót think about making led cubes. A friend of mine built a 4x4x4 cube a while ago, which I helped programming. (We have this deal that if he needs something programmed, I will do it for him as long as he keeps supplying me with pizzas.) After that, since I already had the code, I built a small one too. (pic 1)

I wanted more than just the small single-colored cube, so I started building an RGB cube. (pic 2). Soldering the thing was terrible though. Each led has 4 pins, only spaced 0.6mm (0.02in) apart, so it was really hard not to accidentally solder some together. It did finish soldering it, but I haven't made the PCB's for it yet.

My friend took the other route, and started building an 8x8x8 cube. (see video). It took him ages to complete, (which makes sense, since there are 1024 leads that need to be soldered), but it was more than worth it. Luckily the same type of hardware could be used, but the old code I used for the small cubes wasn't fast enough for the big one, so I had to rewrite the entire code from scratch. This took quite a while, (and a lot of pizzas), but I'm very pleased with the way the code turned out. I do still have to program some extra modes.





zondag 24 november 2013

Amplifier

My old amplifier broke down a long time ago, and the one I've been borrowing since died on me too. So I built one!

It uses two power op amps, which I have a course dedicated to at school. So making this wasn't that difficult. The box is made from old laminate flooring, and I used an old processor heat sink to cool everything. Instead of making a PCB however, I soldered all the components directly to the op amps. It works, but turned into a big mess, so I don't think I will do it like this again. The only things I need to really finish it are some RCA-connectors, and a nice big volume knob. Although it doesn't really look the part, it sounds way better than expected. 







Bandportraits

I promised to post some of my photos here aswell, so here is some of my band photography.









Beerlight

I once posted a picture of a beer crate on facebook. Since I tend to put lights in everything I can find, a friend asked whether it was a lampshade or not. As a reply I sent: "Do you want it to be?"

He said yes.

Music video

A friend asked me whether I'd like to shoot a music video for his band. I did! Here is the result.


dinsdag 15 oktober 2013

Lamp

Another sound reactive light I made. It's based on the same hardware I used in the 'light boxes' a few posts down, but has 8 'pixels' instead of 5.





dinsdag 17 september 2013

Longboard 2.0

I upgraded my previous led longboard! It now uses an atmega328 microcontroller instead of a ready made led controller, so I don't have the remote anymore. I do now, however, have a hallsensor near one of my wheels. Together with the microcontroller and a magnet I put in the wheel, I can now measure my speed, and make the leds respond to that in any way possible. 

In the video the hallsensor isn't there yet, it's just displaying the modes I programmed for the leds. (I'm pushing the buttons with my foot.) I also used one of the modes as a battery indicator.

dinsdag 6 augustus 2013

Light

I made a new light to illuminate my room. It's an 100 watt RGB led, in a glass ball I picked up at a thrift shop. It, like most things I make, uses an atmega328 microcontroller. 

In the video there is no mode switch yet, it's just cycling through the programmed modes. 


zondag 16 juni 2013

Lightboxes

A friend of mine had the idea to make ordinary lightbulbs react to music, for a large event he was organizing. We put our heads together and a month later we ended up with these.

In each box there is an atmega328 microcontroller, an msgeq7 "spectrum analyzing" IC, two shift registers, two transistor arrays, and five strands of rgb led strip. The spectrum analyzing IC allows the boxes to react to 7 different frequenty bands, but only the lowest two (63hz and 160hz) proved to be visually interesting.

The music we tested them with on the video was most obnoxiously dynamic music we could find. Might not suit a lot of ears, but it suited the lights. We still have to make a better video though.






Longboard

I really wanted to have a longboard with led lighting. So I built one!







Bal

A bit of a random project. I found a nice big glass ball at a thrift shop, and obviously had to put some leds in it. The plan however was to be able to project some sort of vague images in the orb, but the angle of the leds was too wide, so almost everything merged together. This made the led ball more interesting without the glass ball than with, so I set the glass ball aside for another project. As with the previous project, I designed the plastic parts in sketchup, and printed them with my reprap. I am thinking if switching to solidworks though.