New Oscilloscope


Since I was very small, I wanted an oscilloscope.

As a child in the 80s, this was a nearly impossible want. New ones were unthinkably expensive, while used ones were rare in working condition. I eventually did get my then tiny hands on a clunky, heavy, rack mounted unit with a screen the same color as Thai iced tea. It never worked, of course, but I didn't figure that out until years later. Eventually, it ended up in the bin with a lot of my childhood things.

That never stopped me from wanting one. When I got back in the amateur radio in 201!, I did shop around a little. The situation was very much the same as during my childhood. New scopes were still a lot of money, and used ones somehow got even rarer. I didn't understand how this was possible. I assumed it was the consumerization of all tech to blame. Less people wanted or needed such a specialized piece of test equipment. I quietly consigned the want to the mental bin along with the rest of my childhood things.

Something happened between then and now, however. Scopes not only got cheap, good scopes got really cheap.If you buy a smartphone off-contract today, you'll likely spend between $300 and $700USD on it. New "beginner" scopes now cost about the same: $350 to $700. When I first found out about the Rigol 1052E I was astonished. Here was a pretty solid, dual channel digital multi-signal oscilloscope for only $400. As much as I wanted it, I could never justify the expense between home repairs, groceries, college loans. 

Then Rigol introduced the successor, the 1054Z. This scope was just astonishingly good for the price tag. Four channels, a color widescreen, 50MHz bandwidth and 1 gigasamples per second. This wasn't just a good scope, this was a probably the only one any hobbyist would need. Still, I couldn't afford it. Furthermore, I felt unable to take on another project with my on-going coding projects lagging seriously far behind. Then as the holiday season rolled around I found myself in possession of a gift card and a unusually good month of finances. I tried to find something more practical on which to spend my good fortune, but nothing really stood out. I again came back to that childhood want to peer inside circuits and see what they're doing with inhuman eyes.

Some months ago, I built a tiny circuit called a "Joule Thief". It's basically a high-frequency oscillator that is used to extract the remaining power in a "dead" battery to light an LED. I built it practically blind, only using some on-hand parts and a diagram I pulled off of the Internet, it worked, but I didn't know why or what it's characteristics where other than "the light's on". The idea to peer inside that little circuit was just too irresistible. 

I did have one additional bit of motivation to get a scope. I know enough theory to guess as to how a circuit works, but often I don't have the gut instinct to back it up. It had the hollowness of knowledge that comes from only reading, and rarely experiencing first hand. I have this same problem with languages. I studied Spanish for two years in high school, and French for a year in college, and I barely remember anything about them. When I worked a consulting assignment in Germany for almost 6 months in 2007, large pieces of that language stuck with me. I had hoped that the same would be true with electronics given the "physicality" an oscilloscope provides.

Over New Years Eve and Day, I spent a few hours poking around the Joule Thief with my scope. Already things seem to be making more sense than they have in years.