Building the $100 night light, Part I

As a first "basement electronics" end-to-end project, I wanted to find a circuit easy enough to involve my child as a lab assistant.  To move the process along, we used Google to find a basic circuit as a starting point, and settled on the following from Red Circuits:

Battery Powered Night Lamp

This circuit uses a 555 chip to pulse an ultra bright LED while powered by a single AA battery.  It also contains a photosensor to disable the LED during the day (battery conservation).  With a component count of around a dozen, it had just enough parts to be interesting, but not too many to lose my lab assistant's attention.

The plan for this project was simple: to build a self-contained/usable project that doesn't look like it was built in a basement (well, at least not have wires hanging out of it/etc., at the end of the day, it still looks cheap).

This project involved the following steps: finding/updating a circuit, identifying/purchasing components, using a breadboard to connect the parts, designing a permanent PCB, using a fabrication house for PCB manufacturing, then finally soldering and assembling the product.

During the course of the project, I estimate the expenses ran about $100.  In real world terms, this is an absolutely ridiculous price for a nightlight which could probably be purchased on Amazon for a few bucks.  However, the goal of this project was mostly educational, so the project costs were not meant to be comparable to an off-the-shelf project.  The costs also included a number of tools I didn't own, which are obviously one time costs which will reduce the costs of future projects.

This project took about a month to complete.  That is an end to end time, from research to final product, which includes slack time such as waiting for FedEx/etc.  The final product is pictured below:

Over the next few posts I'll document the entire process.