A journal of hobbies
I've wanted to build a weather station for a long time, probably for at least 30 years. Droughts are common here, and we rely on rain for all our household water. Our house is also quite exposed to strong winds. At one point a neighbour a couple of kilometers away had their roof blown off... Continue Reading →
Ever since I started tinkering with Arduinos I’ve wanted to build a shortwave receiver using a Si5351 oscillator to tune the frequency. When I saw and built the Soldersmoke Direct Conversion receiver I immediately saw a chance to give it a try. While I've dabbled a lot with Arduinos, I have never used the Si5351.... Continue Reading →
I’ve never owned a proper set of helping hands for soldering, so I can’t tell you how good they are. I've tried using metal spring clams, but that didn't work well. For the last few years I've been using blu tack the Julien Illet way. https://www.youtube.com/watch?v=iZygyqx6AOY It works well, but sometimes I just need to... Continue Reading →
The ESP32 can be set to wake up from sleep due to one of several pins going high. Which pin caused it to wake up? This has been causing me a few headaches with my combined mailbox and driveway monitor because sometimes multiple pins can be high at once. While researching this I also discovered... Continue Reading →
The mailbox and driveway monitor that I built has a 12X2 LCD screen. I know these are not as fancy as many newer displays, but I like their simplicity. The screen in this project runs all the time, usually displaying the time. When mail is delivered, I wanted a coloured visual alert as well as... Continue Reading →
My main Arduino project for the last few months is trying to design and build a monitor that wirelessly sends an alert to the house when mail has been delivered in the mailbox or a vehicle goes through the front gate. I wanted the sender unit to be solar powered and use an ESP32. Reed... Continue Reading →
Update 14 April 2024: I've discovered that it is not necessary to calculate bitmask values for the ext1 external wakeup with the ESP32. There are predefined definitions that you can use. If you are interested check out my post ESP32: Wakeup from multiple GPIO sources and using predefined pin definitions instead of bitmask I'm currently... Continue Reading →
So you have a sensor connected to your microcontroller. How do you calibrate it, particularly if the values from the sensor are not linear? That's a problem I have thought about before and it came up again yesterday when I wanted a project to monitor a battery voltage level. The current project that I am... Continue Reading →
Most of my projects are fairly simple, low powered and run off 5V. Until recently I've used a cheap USB hub plugged into an old iPad charger. This actually worked fairly well, other than the hub connections being a bit dodgy. However, I wanted to be able to switch individual items on and off. You... Continue Reading →
One thing that I've noticed since the pandemic started is that there are far more online meetings in general and also interviews on TV where the guest joins remotely via the web. I like both of these. While not having guests travel to studios is usually fine, sometimes I feel it could easily improved if... Continue Reading →
Garry's blog 