I am fairly new to HA but was able to get my rtl_433 SDR data into HA (at least I can see it in the rtl_433 add on. However, I can’t see anything coming through in MQTT Explorer. I tried changing advanced settings in MQTT Explorer by adding rtl_433 as a topic, but still nothing. Here are the relevant screen shots. Thanks!
I found an answer after hours of searching. For anyone else who comes across this, rtl_433 only ouputs to the terminal by default. You need to tell it to ouput to mqtt as well.
I did this with the following file by using file editor then navigating to /homeassistant/rtl_433/rtl_433.conf.template and entering the following:
output mqtt://${host}:${port},user=${username},pass=${password},retain=${retain}
report_meta time:iso:usec:tz
frequency 433.92M # Example frequency (adjust for your region/sensors)
Add other settings like specific protocols or gain here
You don’t have to enter host, port, username etc, it will pull that from somewhere. More info is
here