Vaudeville halloween

Me and my friends Jowan Sebastian, Tom Brimson and Liam Dennis wanted to organise a night that could double as a showcase for fun interactive things that we wanted to make. Halloween seemed like a good night for that.

With the help of Jack Williams, we put on the night at 5 below. My addition was to help create some sound effects buttons that were placed around the bar and fed through the main PA and help create a big LED filled crucifix.

The sound effects were made using a board based on Lady Ada’s Waveshield, similar to the board I made for my Mario Lamp. It consists of an Arduino shield that reads WAV files off an SD card and plays them out through a 3.5mm jack. There are 6 buttons that trigger 6 different sound effects. I made it using SMD components so I had to rejiggle the original design around a little in Eagle. Here is the board and the schematic.

This is the audio player, housed within a wooden box. 3 of the 6 buttons are mounted in the lid, for the DJ to operate.

The remaining 3 were placed inside dolls and attached around the bar.

As well as the sound box, we constructed the cross. We made MDF boxes to house the lights and covered them with tracing paper and perspex to diffuse the light.

Here is the crucifix assembled in the bar with an automatic RGB sequence.

As every halloween party needs, A spooky rupert the bear poster.

Mario light

It was my friend Scott’s birthday and I was wondering what to get when I thought about the idea of this coin cube light from Mario, then I thought it would be good to add in a sound effect for when it turns on and off. Below is a video showing it going on and off and on and off.

After a bit of research I decided to go for a design based on the WaveShield by LadyAda with an Arduino all on one board. This could then control a relay to turn on and off the light. I basically used the same design as the waveshield, using an SD card with a DAC and an Op amp and a buffer to help things along. I used the same parts as the original WaveShield but used SOIC packages instead of DIP and left out all the other headers. I added in space for an Atmega328 with the Arduino bootloader and a crystal as well as a 5V and 3.3V regulators. It all fitted together onto a pretty small board. Below is a schematic and board image. In hindsight, something I would definately change is to give the mains side of the relay a lot more space away from the other bits, as well as add in a fuse onto the board. You can download the Eagle files at the bottom.

I breadboarded it up by making little breakout boards for the SOIC parts.

Once this was all OK, I cut out the PCB on the milling machine, then soldered it all up. I used a little tube of solder paste and daubed it onto the copper pads using a pin. It’s pretty monotonous doing this, but it’s satisfying when you use the hot air gun to melt all the solder joints together.

Next was to test out whether the relay works with the light bulb. All the electronics are mounted into the central column, which is a piece of 82mm drain pipe, so I fixed them onto a board with  a small power supply that I took out of a 6V walwart. This is probably a pretty dangerous way of doing things. At least it’s a bit scary working with mains electricity and I always imagine everything just melting and burning.

So once all the electronics was done, I got on with making the actual lamp. It was quite a simple design with a base attached to the bottom of the column and a shelf piece that attaches to the top of the column. The light sits in the middle of the shelf, with the speaker to the right. A perspex box fits onto the shelf, with a button in the top. I’ve included some PDFs with the plans at the bottom of the page.

To attach the drain pipe to the wooden base and shelves, I used machine scews going into some M4 threaded inserts. The inserts make things a little bit easier, especially when you’re taking things apart a lot for adjustments. Below are some photos showing it being put together.

The mounts used to attach the shelf to the column.

I bolted the column onto the supports then glued them onto the shelf. I used polyurethane glue, because it’s quick and there was some lying around in the workshop, but any wood glue would do. You can see the light fixture in this picture, also mounted into the middle of the column.

After cutting out and sanding the piece of plywood I used for the base, I routed a groove for the light flex to come out from.

Here is the perspex box that I used for the main cube shape. I cut 4 near-squares from 3mm clear perspex and glued the edges using Tensol 70. I’ve used bison glue before, which has a lot less harsh vapours, but is really runny and quite dificult to stop the join getting bubbles in it. Tensol is quite pricey but I think it’s worth it. If you use it, make sure you do it in a VERY well ventiled place.

Here’s a picture of the light after I sanded the perspex box. I couldn’t resist assembling it. I sanded the perspex to help diffuse the light coming from inside. This allowed me to be slightly less cautious when gluing together the perspex, because I could sand back any bits of glue that oozed out the edges.

Here I applied the graphics that I printed. They were just inkjet printed onto tracing paper. I then sprayed quite a fair amount of Photomount-style spray glue before applying. Once applied, I used the edge of a stanley knife blade to scrape a slight bevel onto each edge, to make the graphics a be little tougher against peeling off.

Painting time. The bits used for this light, were pretty easy to paint with spray paints really. Just a few coats. I just used grey primer for the wood bits then varnished them after.

And here’s the finished thing.

Here’s a view from underneath, showing the speaker and the bolts used to hold the perspex lid onto the shelf.

One last image showing the ‘Mario red’ gaming button used to tell the light to do its lighting thing.

Things I’d recommend to do better would be to be careful when gluing the perspex together because ozing bits at the joint come through and can be seen from the outside. Also, as mentioned before, I think it would be a good idea to do a little redesigning of the circuit board so the mains are a little more isolated. I think it would be a good idea to add a cover to the bottom of the column as well, something I didn’t do.

Feel free to leave any comments and if anyone does get round to making one, I’d love to see some pictures!

If you’d like to buy a readymade one, email me    laurence [at] conceptshed [.com]

You can download the Eagle files and the Arduino sketch here (you need the waveshield library which you can get from Ladyada’s site)

I’ve just set up the github, so sorry if it doesn’t work smoothly. Click on downloads in the top right hand corner to download the files. And here is the partlist with the Farnell order codes, totaling £12.01!

You can view a PDF plan owith dimensions of all the different parts here

LED card

I’ve been thinking about making an SMD LED card for a while and as my friends Ky and Jenny were departing from Falmouth for Brighton, I though it would make for a good present. Here’s a video of the finished thing.

I started by drawing out the circuit schematic in Eagle. I based it around the videos I’d seen for making a LED knightrider circuit using a 4017 decade counter and a 555 timer. Here’s a link to the page I used.

A basic explanation of how it works is that the 555 timer is set up as an astable pulse generator, so the ouput of the 555 oscillates between 0V and 5V(low and high). This is routed to the decade counter. The decade counter has 10 outputs, 9 of which stay low and 1 is high. Each time the 4017 input goes from low to high, the output pin that is on moves to the next pin. This basically cycles through the ouputs, which are in turn connected to groups of LEDs.

Each ouput pin of the 4017 drives between 1 and 5 LEDs. This requires between 20 and 100mA of current. The 4017 is only rated to give 20mA so I had to put a MOSFET inline with each ouput. This acts as a switch that only uses a small amount of current to turn on or off but connects the LED groups directly to the main power lines.

To adjust the frequency of the 555 output, which changes how fast the 4017 cycles through the LEDs, I added in a very small potentiometer and also a surface mount slide switch.

Below is a schematic and parts list which includes Farnell order codes.

Part Device Value Farnell order number
BAT1 AA battery holder 908733
BAT2 AA battery holder 908733
C1 0805 capacitor 1uF 1828853
C2 0805 capacitor 10nF 1414662
C3 0805 capacitor 10uF 1833812RL
IC1 CMOS decade counter CD74HC4017 1739754
IC2 SMD timer NE555D 1737167
LED1 0603 LED pink 1685073
LED2 0603 LED orange 1710526
LED3 0603 LED orange 1710526
LED4 0603 LED orange 1710526
LED5 0603 LED green 1226372
LED6 0603 LED green 1226372
LED7 0603 LED green 1226372
LED8 0603 LED green 1226372
LED9 0603 LED white 1716769
LED10 0603 LED white 1716769
LED12 0603 LED white 1716769
LED13 0603 LED white 1716769
LED14 0603 LED white 1716769
LED15 0603 LED blue 1686063
LED17 0603 LED blue 1686063
LED18 0603 LED blue 1686063
LED19 0603 LED blue 1686063
LED20 0603 LED blue 1686063
LED22 0603 LED blue 1686063
LED23 0603 LED green 1226372
LED24 0603 LED green 1226372
LED25 0603 LED green 1226372
LED27 0603 LED yellow 1226417
LED28 0603 LED yellow 1226417
LED29 0603 LED yellow 1226417
LED30 0603 LED yellow 1226417
LED33 0603 LED white 1716769
LED34 0603 LED white 1716769
LED35 0603 LED white 1716769
LED38 0603 LED white 1716769
LED39 0603 LED white 1716769
LED40 0603 LED pink 1685073
LED44 0603 LED pink 1685073
LED45 0603 LED pink 1685073
LED49 0603 LED pink 1685073
LED50 0603 LED pink 1685073
Q1 SMD transistor MOSFET-NCHANNELSMD 1758065
Q2 SMD transistor MOSFET-NCHANNELSMD 1758065
Q3 SMD transistor MOSFET-NCHANNELSMD 1758065
Q4 SMD transistor MOSFET-NCHANNELSMD 1758065
Q5 SMD transistor MOSFET-NCHANNELSMD 1758065
Q6 SMD transistor MOSFET-NCHANNELSMD 1758065
Q7 SMD transistor MOSFET-NCHANNELSMD 1758065
Q8 SMD transistor MOSFET-NCHANNELSMD 1758065
Q9 SMD transistor MOSFET-NCHANNELSMD 1758065
Q10 SMD transistor MOSFET-NCHANNELSMD 1758065
R1 0805 resistor 82k 1100327
R3 0805 resistor 120R 1738947
R4 0805 resistor 39R 9334467
R5 0805 resistor 30R 9334297
R6 0805 resistor 24R 9334181
R7 0805 resistor 24R 9334181
R8 0805 resistor 120R 1738947
R9 0805 resistor 39R 9334467
R10 0805 resistor 30R 9334297
R11 0805 resistor 24R 9334181
R12 0805 resistor 24R 9334181
U$1 0805 resistor 50k 9608257


Once I had the schematic sorted, I went about laying it out on the board in Eagle. After spending a while laying it all out I printed the design to a PDF using CutePDF to ouput it as a vector image to do some graphic editing.

I could then open it up into Illustrator and play around with the lines. I added in some text and made a few of the signal lines curved.

At this stage it could be used as an etch resist pattern for use with the toner transfer method or similar. I use a little Roland MDX15 CNC machine. It uses a print driver that I have to create the cutting lines. I did this by using the offset path function.

Here’s some images of cutting it out

I then had to do some of the most fiddly surface mount soldering I have done, but it turned out OK in the end.

How i learnt to knead time, or my arduino intervalometer

So I made a Intervalometer for my Canon 400d camera at last. It’s another one that’s been in the endlessly long pipeline for a while. I based it on the wonderful Arduino and got a bit of code off the person that made the Intervaluino whic can be found here.

It was an excersize in how to design a PCB in Eagle and then mill it out on the Roland MDX-15 milling machine at work. At first I did a version of the Intervaluino, but one that all fit onto one board that was a shield that fit onto the arduino. I didn’t realise how cool making shields for the Arduino is before. They just clip together like lego and you can just stack them one after the other. Anyway I found that the 20mA or so that the Arduino gave out wasn’t enough to trigger the relay. After a brief lesson in transistors from Sam I put together a circuit that would definately trigger the relays and had an LED for both the focus and shutter lines.

Above is the schematic of the final circuit. Basically what happens is the Arduino pins 8 and 11 go hi to 5V, making the circuit around the realy. This puts out about 20mA, which isn’t very much,  so they turn on a transistor which allows the relay to access the current it needs to turn on. There’s one relay that connects the camera’s focus trigger to ground, which makes the camera focus and one relay that connects the camera shutter triggger to ground to take a picture. When taking time lapse movies it’s best to use manual focus so the focus pin is slightly redundant, but just in case….

I went through a few versions before I got the final working one.

I milled out 4 boards and populated and soldered 3 before I had one that finally worked. Frustrating!!!!

This is the first one. This is just cutting out the tracks with an engraving piece and not cutting away the unused copper. This makes it harder when your soldering, in case you make a mistake.

As you can see on this version, I had set the tracks too thin and hadn’t left enough room at their sides to mill away the unused copper.

This one is almost there, apart from I forgot to flip the pattern over. To make the components be on the opposite side from the Arduino, so they would fit on, I would have to solder every one onto the top side of the copper, whic is WAY too tricky for my patience.

Here’s that final version, with the bottom photo showing it connected to an Arduino and a 9V battery pack with the 2.5mm jack that connects to the camera coming out.

Message me if you want any of the files or if you know how I can upload them here.

Finally here’s a video made using it

Pulsing LED ping pong ball

So it was my friend Scott’s birthday and I thought he deserves a pressie so I made him this pulsing ping pong ball thing. I originally wanted to have an RGB LED cycle through a load of colours sort at random similar to the processing sketch I did here. I didn’t know how to code the PIC chip to do that though so I just borrowed Jowan’s one that he’d made to puls on and off and routed 3 switches through the red green and blue connectors of the LED.

I realised that I could hide the word if it is written in ink that’s the same colour as the light, so blue text dissappears under blue light. That’s cool but it just hides one out of three words. I think it’d be better if it hid 2, so only 1 shows. Maybe if I wired the LED so that each switch lights up 2 colours to produce cyan, magenta and yellow, it would only light up 1 of the words. Next time next time.

Pretty pointless and shamelessly geeky but Scott seemed to be not too offended so that’s OK.