Taste The Code

18650 Battery Tester Review: Measuring Capacity and Internal Resistance

Testing salvaged 18650 cells from old laptop batteries using a 4-channel tester to measure capacity and internal resistance on each cell independently.

Mar 28, 2026 — 5 mins read

Diagnosing and Repairing a SANKEI TCR95 Studio Mixer from the 80s

I opened up my mom's vintage boombox to bring it back from the dead. A bad switch contact and a possible short were keeping it from working at its full potential again.

Mar 20, 2026 — 5 mins read

Full Electrical Isolation for Your ESP32 Power Switch Using an Optocoupler

Using an optocoupler instead of a transistor in a custom PCB power switch gives full electrical isolation and removes noise from MPPT solar charge controllers.

Mar 13, 2026 — 5 mins read

Inside a Plasma Ball: Testing, Replacing, and Learning from Failure

I attempt to repair a USB-powered plasma ball by diagnosing a blown transistor, replacing it, and exploring why the lightning effect stopped working.

Feb 21, 2026 — 6 mins read

Building a Simple Indoor Asset Tracking System With RYUW122_DK

I set up an ultra-wideband asset tracking system using Reyax RYUW122_DK kit to precisely track an RC car's position in real-time.

Jan 30, 2026 — 9 mins read