Author Archives: mathscinotes

Rigging Cables is Really Important

Quote of the Day History is a tool used by politicians to justify their intentions. — Ted Koppel I have been rather frustrated lately with the number of field failures I have encountered that are related to the humble cable … Continue reading

Posted in Electronics, Personal | 6 Comments

Example of Error Calibration

I was reviewing a test report today for an optical receiver with an integrated power measurement sensor. This sensor is not particularly accurate -- its accuracy was specified as within ± 3 dB of true. This is not good at all. As I looked at our test data, I immediately noticed that I could calibrate the sensor to get a much more accurate result. But as I continued to think about the problem, I decided not to calibrate the sensor. The decision was driven by the cost of calibration versus the value of a more accurate result to the customer. Let's look at how I made this decision -- no magic here -- just a common engineering tradeoff. Continue reading

Posted in Electronics | Comments Off on Example of Error Calibration

Tire Pressure Math

Quote of the Day Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen. — Sir Winston Churchill Introduction I woke up this morning to a rather brisk temperature … Continue reading

Posted in General Mathematics, General Science | 10 Comments

A PCB Thermal Computation Example

I am doing some self-training on electronic thermal analysis. As part of my self-training ritual, I often work through vendor application notes. This post will show how I work through an application note using Mathcad. I chose the Apex SA57 evaluation board (Figure 1) because Apex had the most complete worked example that I have seen. Continue reading

Posted in Electronics | 6 Comments

Wasted School Time

Quote of the Day Censorship reflects a society's lack of confidence in itself. - Potter Stewart Introduction I frequently talk to young engineers who have just completed university. I am always curious as to what they studied in school. I … Continue reading

Posted in Osseo, Personal | 4 Comments

Times of Latest Sunrise and Earliest Sunset

Quote of the Day The road to wisdom? Well, it's plain and simple to express. Err and err and err again, but less and less and less. — Piet Hein Introduction I have lived most of my life in Minnesota, … Continue reading

Posted in Astronomy, General Science | 3 Comments

Benjamin Franklin's Long Term Financial Planning

Quote of the Day The secret of joy in work is contained in one word -- excellence. To know how to do something well is to enjoy it. - Pearl Buck Today, my youngest son and I were talking about … Continue reading

Posted in Financial | 2 Comments

Boyle's Law in the Movie "Men of Honor"

Quote of the Day I understand that sometimes you have to win ugly, but I see no advantage in losing ugly. — Pat Buchanan, political commentator. I do not watch many movies and the ones I do see tend to … Continue reading

Posted in General Science | 6 Comments

The Biggest Ball Lens I have Ever Seen

Quote of the Day The most important thing in the world today is that England and the United States speak the same language. — Otto Von Bismarck We use tiny ball lenses all the time to mate our fibers up … Continue reading

Posted in Fiber Optics, General Science, optics | Comments Off on The Biggest Ball Lens I have Ever Seen

Mathcad Example Using Decibels

Quote of the Day I learned filmmaking by studying the Old Masters - and by that I mean John Ford, John Ford and John Ford. — Orson Welles Introduction I have been working on a software requirements document that involves … Continue reading

Posted in General Mathematics, optics | 7 Comments