Once upon a time, this was a water bottle. The light bulb in our storeroom blew back in February. The ceiling in that room is high enough that replacing the bulb from a stool isn’t do-able and the layout of our place (little doorways, narrow hall, and tight corners) makes maneuvering the fiberglass stepladder ladder […]
There may come a time when you need to know if a container being filled with liquid that flows at a slow, variable rate is nearly full so that you can empty the contents or do something else with the stuff inside. Such a need recently arose here and I put something together using an Arduino (Cloneduino) Nano, a couple of non-contact capacitive water level sensors, a WS2812 LED breakout board, and a piezo buzzer.
Here’s the setup I tried: a cut-off length of white silicone foam (with a 15mm x 20mm rectangular cross-section), a roughly square piece of stainless steel mesh, and binder clips securing the mesh against the foam. On occasion, one needs or wants to solder wires to a small and irregularly-shaped component. Last month, I tried […]
Here’s a zoomed-in image of my attempt to connect to an SCD41 sensor without soldering wires onto it or cobbling together some sort of jig with pogo pins. I recently got some SCD41 sensors. They report CO2 level in PPM as well as temperature and humidity. They’re also surface-mount, of the LGA variety and small […]
One of the calibration slides, with the 1-mm-per-division scale above a new surface-mount CO2 sensor from Sensirion. I hadn’t aligned the start of the scale with the left side of the sensor yet, but it’s 1 centimeter (10mm) square. The trend seems to be that the share of interesting new thingamajigs and doodads available only […]
The “before” view of my second experimental setup. Three types of PTFE tape, two PTFE-impregnated glass fiber tapes and one straight PTFE tape, all with silicone adhesive, under test. How do you hold components in place while soldering? Not the PCBs on which the components are mounted. PCB holders and PCB vises can be pricey […]
The plastic countertop soap dishes we’ve gotten have ridges intended to keep the soap bar a millimeter or so above the rest of the dish surface. Those ridges are a bit on the wide, long, and numerous side, however, and the result is that the parts of the bar that contact the ridges stay moist longer than the rest of the bar and those areas often feel mushy the next time one grabs the soap.