code name: Gameboy of Judah is an analog dubsiren and digital delay originally commissioned in 2015 by Subcreature (Brendan Connors).
The enclosure and PCB were both etched using ferric chloride. I wish had documented the process, but there are plenty of good resources out there for both enclosure and PCB etching. PCBs are pretty easy to etch due to the price and availability of boards with photo-reactive etch resist on them. Enclosures are a bit trickier and require a good bit of patience and willingness to f*** up. This involved a hot iron, toner transfers, and packing tape to cover where the transfer bubbled up. While it is a really fun process, it's the type of thing that you should make multiples of if you're going to go through the trouble. The process isn't too bad, but prep and cleanup take some time.
This circuit uses 555's to supply the voice and pitch LFO. The delay is a PT2399 wired up almost exactly as shown in the datasheet's example circuit, I believe I changed some pot/resister values, but not necessary. Most the components, at least on the actual board, I already had laying around which resulted in the spontaneous prototyping session thats pictured. After I felt like everything worked the way it should, I drew up the schematic in EAGLE.
The layout was designed so that not only did I only have one side to etch, I also didn't have to drill any holes. This isn't the first time I've etch boards to be thruhole-surfacemount... who has time to drill all those holes?
After finishing this siren for Brendan, Tony Norton from analogcraftsman commissioned a smaller, stripped down version, to be used as a learning tool. Pretty much the voice and LFO minus some control and the delay.(Pic in gallery at bottom)
Since finishing this project, I start laying out a 2-side board but the projects been shelfed for some time.