## Painting with Light to Measure Time

December 26, 2020

Recently I was faced with a dilemma while working from home. I needed to verify an implementation of first-order sigma-delta modulation used to adjust LED brightness. (I have described this in more detail in Modulation Alternatives for the Software Engineer.) I did not, however, have an oscilloscope.

And then I remembered something, about a technique called “light painting”: basically a long-exposure photograph where a...

## Metal detection: building the detector

IntroductionBefore starting, you may want to read this post describing the BFO stage:

//www.embeddedrelated.com/showarticle/911.php

I have detailed the implementation of a BFO stage for detecting metal. Now it has been validated on the bench, the next step is to integrate it in a stand alone instrument for testing on the field. A few things have to be done to reach this goal:

• make a PCB for the electronics,
• house the PCB in a box,
• make a frame to hold...

## 10 Items of Test Equipment You Should Know

When life gets rough and a circuit board is letting you down, it’s time to turn to test equipment. The obvious ones are multimeters and oscilloscopes and power supplies. But you know about those already, right?

Here are some you may not have heard of:

Non-contact current sensors. Oscilloscope probes measure voltage. When you need to measure current, you need a different approach. Especially at high voltages, where maintaining galvanic isolation is important for safety. The usual...

April 19, 2014

Last month I wrote that March is Oscilloscope Month, because Agilent had a deal on the MSOX2000 and MSOX3000 series scopes offering higher bandwidth at lower prices. I got an MSOX3034 oscilloscope and saved my company $3500! (Or rather, I didn't save them anything, but I got a 350MHz scope at a 200MHz price.) The scope included a free 30-day trial for each of the application software modules. I used my 30-day trial for the serial decode + triggering module, to help debug some UART... ## March is Oscilloscope Month — and at Tim Scale! March 6, 2014 I got my oscilloscope today. Maybe that was a bit of an understatement; I'll have to resort to gratuitous typography: I GOT MY OSCILLOSCOPE TODAY!!!! Those of you who are reading this blog may remember I made a post about two years ago about searching for the right oscilloscope for me. Since then, I changed jobs and have been getting situated in the world of applications engineering, working on motor control projects. I've been gradually working to fill in gaps in the infrastructure... ## Oscilloscope review: Hameg HMO2024 March 28, 20133 comments Last year I wrote about some of the key characteristics of oscilloscopes that are important to me for working with embedded microcontrollers. In that blog entry I rated the Agilent MSOX3024A 4-channel 16-digital-input oscilloscope highly. Since then I have moved to a different career, and I am again on the lookout for an oscilloscope. I still consider the Agilent MSOX3024A the best choice for a... ## A Useful Current Profiling Method July 2, 20123 comments In one of my recent projects, I had to capture the dynamic current profile of a short-range wireless embedded platform for a number of operation scenarios. Due to the dynamic nature of the current consumption involved, I was unable to use a standard voltmeter for this job. On the time axis, I needed a minimum resolution of 1 millisecond and the accuracy of the current measurement was supposed to be better than 2 mA. This task would be a piece of cake with a Digital Storage... ## Oscilloscope Dreams January 14, 20125 comments My coworkers and I recently needed a new oscilloscope. I thought I would share some of the features I look for when purchasing one. When I was in college in the early 1990's, our oscilloscopes looked like this: Now the cathode ray tubes have almost all been replaced by digital storage scopes with color LCD screens, and they look like these: Oscilloscopes are basically just fancy expensive boxes for graphing voltage vs. time. They span a wide range of features and prices:... ## Oscilloscope Dreams January 14, 20125 comments My coworkers and I recently needed a new oscilloscope. I thought I would share some of the features I look for when purchasing one. When I was in college in the early 1990's, our oscilloscopes looked like this: Now the cathode ray tubes have almost all been replaced by digital storage scopes with color LCD screens, and they look like these: Oscilloscopes are basically just fancy expensive boxes for graphing voltage vs. time. They span a wide range of features and prices:... ## 10 Items of Test Equipment You Should Know June 22, 20143 comments When life gets rough and a circuit board is letting you down, it’s time to turn to test equipment. The obvious ones are multimeters and oscilloscopes and power supplies. But you know about those already, right? Here are some you may not have heard of: Non-contact current sensors. Oscilloscope probes measure voltage. When you need to measure current, you need a different approach. Especially at high voltages, where maintaining galvanic isolation is important for safety. The usual... ## Oscilloscope review: Hameg HMO2024 March 28, 20133 comments Last year I wrote about some of the key characteristics of oscilloscopes that are important to me for working with embedded microcontrollers. In that blog entry I rated the Agilent MSOX3024A 4-channel 16-digital-input oscilloscope highly. Since then I have moved to a different career, and I am again on the lookout for an oscilloscope. I still consider the Agilent MSOX3024A the best choice for a... ## March is Oscilloscope Month — and at Tim Scale! March 6, 2014 I got my oscilloscope today. Maybe that was a bit of an understatement; I'll have to resort to gratuitous typography: I GOT MY OSCILLOSCOPE TODAY!!!! Those of you who are reading this blog may remember I made a post about two years ago about searching for the right oscilloscope for me. Since then, I changed jobs and have been getting situated in the world of applications engineering, working on motor control projects. I've been gradually working to fill in gaps in the infrastructure... ## April is Oscilloscope Month: In Which We Discover Agilent Offers Us a Happy Deal and a Sad Name April 19, 2014 Last month I wrote that March is Oscilloscope Month, because Agilent had a deal on the MSOX2000 and MSOX3000 series scopes offering higher bandwidth at lower prices. I got an MSOX3034 oscilloscope and saved my company$3500! (Or rather, I didn't save them anything, but I got a 350MHz scope at a 200MHz price.)

The scope included a free 30-day trial for each of the application software modules. I used my 30-day trial for the serial decode + triggering module, to help debug some UART...

## A Useful Current Profiling Method

In one of my recent projects, I had to capture the dynamic current profile of a short-range wireless embedded platform for a number of operation scenarios. Due to the dynamic nature of the current consumption involved, I was unable to use a standard voltmeter for this job. On the time axis, I needed a minimum resolution of 1 millisecond and the accuracy of the current measurement was supposed to be better than 2 mA. This task would be a piece of cake with a Digital Storage...

## Painting with Light to Measure Time

December 26, 2020

Recently I was faced with a dilemma while working from home. I needed to verify an implementation of first-order sigma-delta modulation used to adjust LED brightness. (I have described this in more detail in Modulation Alternatives for the Software Engineer.) I did not, however, have an oscilloscope.

And then I remembered something, about a technique called “light painting”: basically a long-exposure photograph where a...