Controlling fan speed on a Barani Design prototype fan-aspirated radiation shield

Recently, I was fortunate to receive a new prototype model of the fan-aspirated MeteoShield Pro from Barani Design. On this version, the solar panels are replaced with two power wires, making it possible to connect an external power source, allowing the fan to be active 24 hours a day. Varying fan rpm is possible by […]

Getting accurate NTC thermistor readings with a Wemos D1 Mini

A thermistor is a very common type of thermometer. They are cheap and readily available in many forms. Thermistors are are simple devices. A thermistor is basically nothing more than a resistor that changes its resistance with temperature. Very popular are 10K NTC thermistors. Negative Temperature Coefficient (NTC) means that resistance drops when temperature rises. […]

Uploading to the Weather Underground API

Since all data processing for Meteodrenthe is custom made, this includes sending updates to Weather Underground (WU). I realize that the name of WU has been tarnished in recent years. Nevertheless, it is still one of the most popular websites for PWS owners. Meteodrenthe uploads data there as well. This PWS page is updated once […]

Reading a PT100 sensor with a Wemos D1 Mini

In my never ending quest for better temperature readings – or other ways of doing so, at least – I’ve begun trying other sensors than the SHT35. One of them is the PT100. It’s supposed to be very accurate. It it used in many different situations, from laboratory settings to industry. It’s also used in […]

Project Apogee part 1: fan aspiration

My big project for the summer of 2021 is adding a fan aspirated radiation shield to my setup. My primary shield – the Barani MeteoShield Pro – is a superb product, but a passive shield it remains. It suffers from overheating in windless conditions. Those conditions do not occur too often at my location, but […]