To My Readers



If this is the first time you're visiting my blog, thank you. Whether you're interested or just curious to find out about PCB reverse engineering (PCB-RE), I hope you'll find something useful here.

This blog contains many snippets of the content in my books to provide a more detailed overall sampling for my would-be readers to be better informed before making the purchase. Of course, the book contains more photos and nice illustrations, as evidence from its cover page. Hopefully, this online trailer version will whet your appetite enough to want to get a copy for yourself.

Top Review

I started doing component level repair of electronics with (and without) schematics more than 40 years ago, which activity often involves reverse-engineering of printed circuit boards. Although over the years my technical interests have shifted into particle beam instrumentation, electron microscopy, and focused ion beam technology fields, till this day——and more often than not——PCB repairs have returned multiple multi-million-dollar accelerators, FIB, and SEM instruments back to operation, delivering great satisfaction and some profit.

Many of the methods described by Keng Tiong in great details are similar to the approaches I've developed, but some of the techniques are different, and as effective and useful as efficient and practical. Systematic approach and collection of useful information presented in his books are not only invaluable for a novice approaching PCB-level reverse engineering, but also very interesting reading and hands-on reference for professionals.

Focus on reverse engineering instead of original design provides unique perspective into workings of electronics, and in my opinion books by Keng Tiong (I've got all three of them) are must-read for anybody trying to develop good understanding of electronics——together with writings by Paul Horowitz and Winfield Hill, Phil Hobbs, Jim Williams, Bob Pease, Howard Johnson and Martin Graham, Sam Goldwasser, and other world's top electronics experts.

Valery Ray
Particle Beam Systems Technologist

Monday, August 3, 2026

Repair, New, or Refurbished?


Question: 

Your plant has a 15-year-old conveyor motor that fails every 4 months. Each repair costs $300. A new motor costs $2,500. A refurbished motor (from a specialist) costs $1,200 with a 1-year warranty. Which path do you choose? What data would change your answer? 

Answer: 

Given: 15 years old, fails every 4 months → 3 failures/year × $300 = 900/year. New = $2,500; Refurbished = $1,200 with 1-year warranty. 

Simple payback (repair vs. refurbished): 

Current annual repair cost = $900.  
Refurbished cost $1,200.  
Payback = 1.33 years.  

After 1 year, warranty covers failures. From year 2 onward, assume refurbished failure rate is similar to current (3 failures/year) → another $900/year. Still cheaper than $2,500 for new. 

Decision: Choose refurbished motor based on current data. 

What data would change answer? 

▪ If the conveyor is a production bottleneck where downtime cost is >$500/hour → new motor (higher reliability) may be justified. 

▪ If the refurbisher's warranty excludes labor, adding $150/failure for installation → refurbished TCO rises. 

▪ If the motor is obsolete and refurbisher uses scavenged parts with unknown remaining life → avoid. 

▪ If new motor efficiency is 10% better, then electricity savings alone could favor new motor over 5+ years.

 

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