Even though I've put a lot of work optimising ZeroPhone for everyday usage, self-assembly and manufacturing, there still are things we can do better in the next revision. Let's go through them, so that you can see the final changes I need to make to the boards, and things I need to figure out before the crowdfunding!

This list is a result of me carrying a ZeroPhone with me through this year - and, therefore, fixing these problems will make sure your ZeroPhone lives as long as possible and is not merely some kind of gimmick that dies after a couple of months. Most of these problems are either fixable or have workarounds - if they didn't, I wouldn't have had been able to assemble the Gamma PCBs. However, they will be problematic for new people, so I have to make sure to eliminate as much of those problems as possible for the next version - to properly achieve the ZeroPhone "self-assembly" goal, making the assembly "as easy as possible" and not just "possible".



Charging and protection boards



We use popular modules from China for the ZeroPhone battery charging and protection. I had problems with the way those modules had to be soldered on the back board - it wasn't straightforward, and it wasn't easy to get done. So, I've flipped the footprint - now it's compatible with more module types, and it's much easier to solder the modules on - the board layout also became much more straightforward, since power traces used to be crossed and now they aren't! The component side of the modules is now exposed to the outside of the phone, though - I'll have to make sure this doesn't cause problems, such as short-circuits (possibly, release a 3D-printable cover).

In addition, there were stability problems with a new version of these modules. Beta boards were using an earlier version:







For Gamma boards, however, I used slightly different modules, a newer version - I ordered them by mistake, so I quickly changed the footprint to fit the new modules in order to avoid ordering the older ones.

That turned out to be a bad idea - the newer modules seem to not function as well as the previous, some of them randomly fail (luckily, they fail safe). It happened to some of my ZeroPhones, and it also happened to some of the ZeroPhones that I sent out (which resulted in the person having to send it back, for me to repair, and that's something I'd really like to avoid). That's not acceptable - if the module is broken, ZeroPhone cannot operate from the battery at all - or it switches off randomly, which is even more annoying. Fortunately, the new, flipped footprint allows for all kinds of modules, so it should be easier to find a suitable board now!

During the manufacturing, we'll need to find a way to either find a reliable source for these modules, or to manufacture our own (I've already reverse-engineered the schematics and the PCB, thankfully, and I'm asking for manufacturing quotes) - as a backup plan in case the commercial modules are no longer suitable for us. I've also tried understanding the problem by comparing "old" and "new" modules - I've checked the schematic and it's the same (the boards are slightly different, but the changes are minimal), so my guess is that the "new" modules are using cheaper components, which causes the failures. But, just in case, I'm going to see if there's a way for us to source these boards reliably.

Reworkability



It turned out that current ZeroPhone PCBs might have some problems while doing repairs - traces breaking, pads being lifted etc. Generally, it will only happen to low-quality PCBs - but it's hard to make sure the PCBs you're ordering are of sufficiently high quality (and if you're ordering from a place like DirtyPCBs, it's likely your PCBs won't be good enough to survive overheating). This is bad, since it makes ZeroPhone less repairable - in the end, I have two back boards and one front board that are unusable because too many pads got lifted, and I also have some more that need...