Solar panels for sensor nodes

Intro For a while now, I started replacing the dead AA(A) batteries in my sensor nodes with rechargeable NiMH ones. So, since these batteries are rechargeable, I thought, why not trying adding small solar panels for sensor nodes, where light is abundant. Node 27: outside sensor Purpose: outside temperature, humidity, light, pressure sensor. Powered by 2 x AAA 500mAh from Ikea. The solar cell is rated 3V, 125mA and is pointing vertically south and costs… Continue reading

HD15 flashlight review

Intro A friend of mine showed me the Wurkkos HD20, so I immediately ordered the HD15, as the smaller version with 18650 sounded more fit. Seemed like the exact thing to have around the house or when travelling and seeing the many positive reviews, I quickly ordered one. So here are my thoughts on it. Good The good parts of the light are pretty obvious and I will not spend much time about it. Here… Continue reading

Simple LED strip UPS

Why? There are multiple LED strips in my home, all of them automated and remote controlled, as part of my home automation system. LED strips are very flexible, both literally and as usage case, easy to control and provide an interesting lighting option. While there are issues with electricity at most once or twice a year, I thought about how it might be good if some of these LED lights might work for a while once… Continue reading

Another two troches with self dimming

Intro When using my new Energizer pivot torch i noticed that it dims itself slowly over 15 minutes from the start, reaching 1/10 of the maximum intensity. The torch does this on purpose and can be reset by turning it off and on again. The HD vision headlamp This lamp is probably my most used torch in my life. Even though I got it about 8 years ago for caving, it saw most action as… Continue reading

An odd torch – Energizer Pivot

Intro I have used 2 types of LED torches: regulated and unregulated. The unregulated ones are the most common and they use some simple circuits for the LEDs, which means that as the battery discharges the light output gets lower. The regulated ones use some circuit to maintain a constant current flow as the battery discharges, for as much as possible. What about the Energizer hard case pro pivot plus? This is an odd one.… Continue reading

Too much sleep power

Intro Plenty of devices are running on power all the time, even when we are not using them. Sometimes all they do is monitor for the user to press a button or interact with the devices, but many modern devices maintain network connectivity. This allows them to wait for some user interaction which may come through a network connection from a computer, phone or other device. Some of these devices are doing so with low… Continue reading

Stop it with the coin cells!

Hey companies making sensors and remotes! (for smart home/home automation and the likes). If you can make a sensor microscopic – fine If it needs to be portable – fine But if it is rather small, but still visible you are not doing anyone any favor by making it as small as possible with a coin cell battery that runs just a few months or even less. If your sensor can run for years and… Continue reading


Intro Tired of plugging in USB HDDs for backup and data storage and looking for improving quality of life, I thought about getting a network attached storage (NAS). It became clear very quickly that I wanted NAS from one of the few big manufacturers like Synology or Qnap because I wanted this to work well and get it up and running fast without issues. Basically I wanted to pay a bit more for a solution that… Continue reading

Why we need USB charging on everything

Intro USB Power Delivery charging is coming to more and more devices, after is has been added to the USB standard along with the introduction of USB-C connectors. The standard allows devices and chargers to talk to each other and negotiate what sort of power devices need, while also talking to cables to see how much current they can carry. It’s been adopted as a universal way to charge many kinds of devices by the… Continue reading

Wet sensors (or humidity sensor troubles)

Intro Well there is no surprise: i went through a lot of temperature and humidity sensors. Some I already reported on, and some more i tried afterwards. And none seem to survive the exterior readout very well. The defects are mostly related to humidity, but not temperature. What happens when they fail: mostly the humidity saturates to 100%. Here is my most recently replaced one from outside, a BME280: After a while, the sensor reads… Continue reading