The first version of this board has two major issues that inhibit the hardware functionality of this project.

First, the relay mechanism doesn't work to switch on the sprayer when excited by the gpio pin. On further research, it looks like a Raspberry Pi Zero W can only source about 16mA of current. This relay needs 50+mA to latch, making this concept inadequate for our feline spraying needs.

Second, the 5V LDO gets roughly as hot as the surface of the sun because I'm trying to drop as much as 14W across it. Since I'm not keen on giving up my security deposit, it would be good to switch this out for another option that's less likely to start a fire. According to various sources online, a switching regulator is better in this arena as it won't get so hot.