It's been a while since the last update as I've been busy with some 3D printer tweaks, waiting on parts, rethinking the approach, and other stuff.

After experimenting with battery life calculation and measuring out dimensions, I'm getting closer and closer to the conclusion that I can't shrink things down to the size I want using the Qt Py, the LiPo BFF and a rechargeable battery. Well, it's most likely doable but I'm quite there in terms of my electronics skills to figure everything out just yet.

The current goal of the project is to get everything working using a 3V button battery (CR2032 or CR2025 most likely), an ATTiny 85, the 0.49" OLED screen seen in previous logs and a switching to the GUVA-S12SD UV sensor. With that in mind I've designed a very optimistic and much smaller case, which nothing fits into right now. The goal is to try to get everything to fit in a similar form factor and a single PCB, you can see the preview below:

The case is made from 2 parts with a slide-in back piece:

And as you can see, the size is significantly smaller compared to the previous 5 version of the case:

The fact it's much smaller makes printing a lot faster so I should be able to iterate a lot faster too and a screw-less design makes things easier to assemble too. 

So, the next step is trying to program the ATTiny 85 to do the work - it's a new chip for me but I've got everything I need to program it using an Arduino Uno. I'll try to get things working and wired up and fit into case with current component setup - if all goes well I'll be able to show this off in the next log. Until next time!