Author Archives: WorkingBear


Jul18
Introduction to Process Capability — Three Common Indicators: Cp, Ck, and Cpk

Cpk is commonly used as an overall indicator of a factory’s manufacturing process capability. However, it can also be applied across different industries to measure the ability to meet a target. A popular analogy is how well you can hit … Continue reading

Jul16
Youtube: QC 7 Tools – Fishbone (Cause & Effect Analysis) Diagram Introduction

Many of you might already know what a fishbone diagram is. But do you know how to actually draw one? And what should you watch out for when creating one? As the name suggests, the diagram looks like the skeleton … Continue reading

Jul10
Customer Complaint About Oil Contamination on PCB: Who’s the Real Culprit? (FTIR Analysis)

In the previous article, Workingbear mentioned a serious DOA (Dead on Arrival) customer complaint involving one of the company’s products. Most of the defective units had unresponsive keypads—specifically the 3, 6, and 9 buttons—and it was eventually traced back to … Continue reading

Jul03
[Case Study] Troubleshooting a Customer Complaint – Keypad Malfunction Caused by Oil & Powder Contamination on the PCB

This article shares a real case from Workingbear’s past experience dealing with an urgent customer complaint. One day, Workingbear was suddenly assigned to fly to a factory in China to “hunt for oil.” My manager even warned, “If you don’t … Continue reading

Jun26
What is Environmental Stress Screening (ESS)?

Environmental Stress Screening (ESS) is a method used to apply certain environmental and operational stresses—such as power on/off cycles, bias voltage, pressure, thermal cycling, and vibration—to new or repaired products (usually electronics or components). The idea is to expose hidden … Continue reading