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I’m working my way through the LAoE lab book Learning the Art of Electronics: Section 1L.6) and am now at the section where I’m first instructed to use an oscilloscope. Lucky for me, I now have one!

It’s not luck. I had to drop some cheddar on this critical piece of equipment, but it’s been something I’ve been curious about since I was in Mr. Klook’s Chemistry class in High School. Technically, it wasn’t the class, it was the darkroom off the side of his class where he kept an old oscilloscope in the cabinet collecting dust that I first saw one. It looked just like the ones in opening credits for The Outer Limits.

More recently, while playing with various synthesizers which manipulate a “sound envelope”, I had considered getting an oscilloscope so that I could visualize the various envelopes I was manipulating. Unfortunately, I knew these were pretty but complex instruments (intimidating?) so I couldn’t justify spending the money and used my ears to determine the differences. It was music, after all. But with the first chapter of LAoE clearly telling me that this was going to be an important piece of equipment to learn, I now had a reason.

Oscilloscopes are fascinating pieces of equipment, able to show you patterns of electrical impulses as they’re happening in extremely fast intervals. It’s almost like a microscope for observing electronic pulses. You’re able to zoom in and see the common repeating patterns (or lackthereof) in the various waveforms that the impulses make. I would encourage any curious person to get even the most basic oscilliscopes. “Catching a wave” pattern and locking it in, then doing things to adjust it are absolutely fascinating excercises.

Plugging the output of the function generator that I recently soldered into the oscilloscope for the first time put a grin on my face so big, you’d think I was a kid who got exactly what they wanted for at Christmas. Lookie! It made stuff! This is me, playing with the wavelength on the function generator while taking some pictures of it.

I also got curious and plugged in one of my miniature Volca Bass synths to see what it looked like. This is not it below. It looked pretty neat though. The most interesting thing was seeing the control voltage that it uses for clock synchronization between synthesizes. It had a very neat dip that appeared to trigger every 1/4th of a beat and adjusted its wavelength as I adjusted the tempo.

This made me want to see some music through my oscilloscope. This is what The War On Drugs song Under Pressure looks like, zoomed way in to just a few nanoseconds of time. I plugged a headphone jack into my laptop, played some Spotify and hooked the oscilloscope probe and ground to the tips of the 1/8" jack. Love this.

I feel like this was a decent accomplishment. The first challenge with an oscilloscope is that you realize it’s hard to just finding the wave (or the “sweep” is the term. I think) on the screen. You can be zoomed in to far on a place where the sweep isn’t visible. After this chapter and playing around with a few other items, I think I’ve got a feel for it though.

In a world where information is the key to survival, sensors and measurement tools are the critical devices that provide that factual information. There is truth in measurements, but there is also deception, in how our biases interpret those truths. Even the tools we use to measure things are limited by our own understanding of the universe.