It’s a big day in the synth workshop — my bedroom. This evening I screwed my first module into the rack! It’s an envelope generator (ADSR style… hence the name). Symbolically, this is a big deal. I first posted about this synth project about 5 months ago and I’ve been doing a lot of work since then. I didn’t originally plan for this to be a modular… but here it is! I’m excited, but there’s a lot to do before I have a usable instrument. Besides needing to panel up my other two modules, I need to build a sound source (at the moment, I’m considering a module that will input an instrument, since it’s simpler to build than an oscillator). I did at least get to test the envelope generator by hooking it up to an analog voltmeter and watching the needle jump around. Cool. Everything was A-OK during the tests I did, so I’m calling it done!
I etched the panel using a mix of muriatic acid and hydrogen peroxide, the same setup I use for PCBs. Learn from my mistake and do not do it this way! The reaction got out of control very fast. There were — likely toxic — fumes billowing everywhere and scalding hot acid furiously bubbling out of control. Not a pleasant way to spend the afternoon. In the end, it worked well enough and my lungs seem to be functioning alright. But next time I’m gonna try caustic soda and possibly use some black spray paint to make the lettering pop out. Talk to you then!