10. Mar 11th-17th: Storytelling review / building final modules#
This week we had a storytelling review! Here is my first draft at slides for my final presentation at the end of March:
During the presentations, Anastasia and Cecilia gave us feedback and advice, including reminding us to refer to the project in the third person, and present it as a finished work instead of going through everything we had done (which I’m documenting here partially to remind myself to remember these things!).
Final module designs#
This week I also adjusted the designs of my synth modules, deciding on the size of the grids, and laser cutting them:
From here I made new versions of the amplifier and 40106 oscillator circuits. I also decided to make a second type of oscillator module, based on the 4046 IC. This is a ‘phase locked loop’ which allows you to make more predictable ‘musical’ pitches than the 40106 does. I again used Nicolas Collins’ Handmade Electronic Music, and Hackaday’s Logic Noise for circuit designs, and built this first in hard format, and then on a soft grid.
Unfortunately the first prototypes I made of my two oscillator modules did not work properly at all. I learned that when the circuit is fully assembled, it’s really really hard to figure out what small thing has gone wrong. I stitched them both again from scratch, and this time:
- In the picture below you can see that there are bits of thread that have been stitched around with black thread. This was an attempt to insulate one trace from another, where two threads needed to cross the same point but not make contact electrically. In my final versions I decided to do this by looping one thread through to the underside of the fabric instead.
- Loops: in my first prototype of the phase locked loop oscillator, I used a lot of tight loops () in the design of the stitching. It looked cool, but I realised afterwards that I had stitched a load of small inductors, and the result of this was that the circuit did not work at all :) Lesson learned. The picture below is of the first oscillator prototype I made, as I didn’t take pictures of the initial phase locked loop prototype.
Other modules#
This week I also got started on what became the Ada and Anni modules - they’re properly documented in the MAKE page of my final documentation.
Sequencer#
I can now make a sequencer using the 40106, a 4017 decade counter chip, and the 4046! But I didn’t take any pictures of this unfortunately…but here is a gif of it working as an LED sequencer. Circuit, as usual, from Handmade Electronic Music by Nicolas Collins, but just search for ‘Baby 8 sequencer’ and you’ll find what you need to make it.