Bluetooth Environmental Sensor Node

Project purpose

A complete low-voltage sensor platform for PCB design, embedded hardware, design-for-test, and documented validation.

Current focus

Requirements, circuit architecture, component selection, schematic capture, PCB planning, and test planning.

Build log

Short updates that keep the project page tied to ongoing work.

August 14, 2026

Phase 1 evidence boundary set

The project is in design and documentation. Fabrication, assembly, physical measurements, and validation remain separate future gates.

Case study

The fuller writeup: decisions, tradeoffs, and what the build clarified.

This project is a complete hardware case study connecting electronics repair and test experience with PCB and embedded-hardware development.

It is a Bluetooth environmental sensor node, but the sensor readings are only part of the point. The deeper goal is to design a board that can be understood, powered safely, debugged deliberately, and tested without improvising the entire process after fabrication.

Current Evidence State

The project is in Phase 1: design, analysis, and documentation.

That means requirements, block architecture, component decisions, schematic work, calculations, applicable simulation, PCB planning, and bring-up strategy may be documented here. It does not mean a physical board has been fabricated, assembled, measured, or validated.

Those words stay separate on purpose:

Designed means the design artifacts exist and have been reviewed.
Simulated means a defined model produced a result under stated assumptions.
Fabricated means a physical PCB was manufactured.
Measured means data came from physical hardware with identified equipment and conditions.
Validated means the hardware passed a written requirement or test criterion.

Design Priorities

The board is being shaped around a few practical questions:

Can every power rail be checked before the rest of the board is trusted?
Are reset, programming, communications, and sensor buses reachable during bring-up?
Do labels and test points reduce ambiguity for the next person at the bench?
Are the expected readings and stop conditions written before first power?
Can a failure be isolated without treating component replacement as diagnosis?

Why It Matters

Repair work teaches you what a difficult board feels like from the other side. Poor access, unclear labels, missing protection, and undocumented expectations turn simple questions into long searches.

This project is where those lessons become design decisions. The case study will grow only as the evidence grows.

Next Gate

Phase 2 begins only when fabrication is intentionally approved. At that point the record can expand to assembly inspection, current-limited first power, rail verification, programming, functional tests, fault notes, and physical measurements.