I’ve been using RTL_433 with a SDR for a few years now with modest success. This setup will detect and identify a variety of 433Mhz sensor readings. The output is piped to a MQTT broker and from there the readings are presented graphically. At first this was done on a Raspberry Pi running a bash script on startup, with the following one liner command. rtl_433 -F json | mosquitto_pub -h <MQTT-Broker> -i RTL_433 -l -t RTL_433/SDR_FEED Unpredictably, problems would arise…
This post will cover the use of the ESP8266 clone form factor of the more popular Wemos D1 Mini. This clone development module has the same pinout and interfaces as the Wemos D1 Mini. The Arduino IDE was set to use the NodeMCU 1.0 ESP12E Module for the code below, although the LOLIN(WEMOS) D1 mini (clone) was avaliable. This board selection didn’t present any issues when loading the firmware. The board is inexpensive, a 10 pack can run around $25….
This post will cover the use of Node Red as a system monitoring tool. Why is this useful? It gives system status at a glance. With some advanced configuration, Node Red can provide trend analytics or automated responses. Here is a comparison of two methods to gather metrics from systems and present them in Node Red. The first method is with the SNMP node. This is centralized because Node Red is the single point that is gathering metrics from multiple…