MQTT topic tree structure improvements

I’ve been unhappy with my old MQTT topic tree structure for quite some time now and did some thinking/research on how to improve it. Google pointed me to Tinkerman’s article on a similar subject, and I started planning on improvements. I will repeat a quote I used in my last post “If you can’t measure it, you can’t…

Duck DNS updater in Node-RED

Dyn and No-IP have been for long time my choice for dynamic DNS, but both have recently made steps towards commercializing their services and implementing monthly confirmation process. I think it is time for me to move away and look for alternative. DuckDNS seems to be exactly what I was looking for, easy to use, reliable…

You watch too much TV

I have the feeling that my teenager son spends too much time in front of the TV. We have a house rule that he is allowed to watch TV only after all homework is done, room is tidied up and for no more than couple hours a day. Of course, this rule is hard to control unless time spent…

NodeRED RFM2Pi to emonCMS gateway

I created a Node-RED RFM2Pi gateway few weeks ago, have it running nicely since then. I decided to use that approach instead of a python script, since it is very flexible, visual and easy to extend. Prior to Node-RED I used the great OEM gateway script by Jérôme Lafréchoux. My inspiration to switch to Node-RED were Nathan…

Detecting AC

I sometimes have home automation projects that require detecting AC voltage (on/off only), previously have experimented with non-contact AC detection. Here is another approach that may be more suitable for low-power AC detection node: using a NE2 neon lamp and an LDR     The bulb will reduce LDR’s resistance and the circuit will read…

My dog as smart wireless DVR sensor

I live in a small village ~25km from Sofia, Bulgaria and commute daily to the city. My house’s alarm system would occasionally ring me and I would rush back home to see if all is fine, that can be pretty inconvenient. For that reason, I installed a basic home security CCTV surveillance DVR system, so…