Quoi de neuf 2021
From Eric
Experiments carried out in the past (from 2011) are described hereafter: 2020, 2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011
February 2021
- I have received by russian CRT and have built the power supplies and the plate drivers. See article osciloscope. Here are a few pictures of the current setup:
- I have completed my "sound spectrum analyser" using a BA3830 and a bunch of LM3914N. A video is available here (definitively non interesting). The PCBs have been built by JLPCB (nice and fast. A few pictures are at Sound spectrum analyzer.
- I have added a Python MQTT client to log the temp, humidity, pressure, etc. data to a mysql database. I use "sqlbrowser" to display the content of the data base. If I find some time, I'll write a Python HMI. Another solution would be to use an InfluxDb database (optimized for time series) and a Grafana dashboard. See tutorial here. I should also probably move to a more robust RPi distribution (e.g., dietpi) in order to prevent the nasty effect of power-cuts on the file system (dietpi allows to set parts of the file system read-only).
January 2021
- I have moved my lab to a new, much larger, room:
- Waiting for the transformer to drive an CRT (see Quoi de neuf 2020, december).
- I have created a LED "spectrum analyzer" using an electret microphone, a 5532 op amp (see here), a BA3830S spec. anal., and a LM3914 LED display driver. Nothing very complicated, but just a way to occupy time. Here is a picture of the breadboard setup: , the scheme and the PCBs
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- I am also playng with my cubecell. I have attached a solar panel, a battery, and a CJMCU-8128 set of sensors. The guy transmits it data via LORA to a ESP32 which ralays them to a MQTT Mosquitto server running on an RPi...
