Assembled: DSO 130 Oscilloscope Kit
2015-10-25 11:45 - Making
I ordered a DSO 138 kit recently, and it arrived yesterday. Much of my evening was consumed with assembling it. This is a simple digital oscilloscope with a 2.4" LCD display, and only a 200kHz bandwidth. That's too low to be of much use, but I have an audio range (only up to 20kHz!) task to put it towards, and it was only $20.
The cheap kit I got came with lots of small parts, and basically none of them labeled, so it took a few hours to put everything together. That went mostly without issue, besides being tiring to lean over the work for that long. Once it was together, it didn't work! Oh no! I stopped for dinner and long story short a few hours later I realized the issue: I used my "proper" electronics power supply, with current limiting. This saves electronics from blowing up if there's problems, by not providing enough power to cause damage. I still had it set too low, so it wasn't providing enough power for correct operation! A twist of the right knob made it all work, and showed that there were no shorts anywhere: current draw stopped at right around the expected value.
All that's left is a bit of the calibration procedure. I just need to find a tiny screwdriver small enough to fit into the tiny adjustable capacitors, the round little green things near the top left of the final picture, between the display and the switches. I got rid of my cheap "jewelers screwdrivers" set when I got a much better iFixit set of drivers, but this is at least the second time that I've found it doesn't have the right thing. When it's the right size they're great drivers, but it's only got one flat head, too wide for this purpose.
Other than that, a nice way to spend a long afternoon!
