Given the current interest in Covid-19 contact-tracing using anonymous (in principle) Bluetooth messages, I've started monitoring the chattering of Bluetooth devices around my house with a Raspberry Pi 3B+, Python and bluetoothctl. I can typically see between 5 and 10 active devices at any one time....

There's a GPIOZERO setting called max_distance that defaults to 1 metre. I set it to 4 metres for my application. My application was detecting not dogs but burglars. I'm not sure the sensor is well suited to reliably detecting one-off events like this, the false-positive rate is too high. It works b...

The Pi is very good for what it is. My concern is when people buy them to turn them into clocks and similar devices, using exponentially more energy and resources than what an actual clock does... I think this is worth noting. I currently have 4 Pis in my house doing various housekeeping/monitoring...

Thanks for the reply. I hadn't heard of gpiozero, but I've just tried it and the results are much smoother. I'm still seeing the occasional rogue reading at 27 or 47 seconds past the minute, but gpiozero seems to reduce or eliminate them most of the time. I will have to investigate further.

I'm trying to create an intruder detector for my house using a Pi 3B+, an SR04 ultrasonic sensor and Python. Most of the time it correctly detects a wall about 3m away (about 20ms roundtrip) but at regular intervals, it returns much shorter distances. It happens about twice per minute, at about the ...

I tried to do a bit of car-detection with the magnetometer on a Sense Hat. It seemed to be able to detect a stationary car (1 tonne, mostly steel) at 3 metres, but not moving cars at 8 metres. It also has a fairly sensitive accelerometer, but I wasn't able to detect the ground vibrations of passing ...

That's an odd method, i never heard of that. how accurate is it ? You can't get any pulse from your meter ? I haven't done a rigourous analysis of accuracy, but my feeling is that the error is less than 20% and probably less than 10%. It helps that my boiler is an older non-modulating model where t...

I don't have a smart gas meter either, so I attached some DS18B20 temperature sensors to the water pipes going into and out of my gas boiler, and use a Pi to estimate the amount of gas used. After a bit of calibration, that gives me reasonable estimates of my gas consumption. I've also discovered so...

@ Simonmsh: The TV Hat certainly looks interesting. What EPG and interface software do you use? I just use TVHeadEnd running on Raspian, which I think is the most common configuration. By default TVHeadEnd uses the standard EPG transmitted with Digital Terrestrial TV, although it can be configured ...

Apologies for not answering the question, but have you considered fitting a TV Hat to your Pi and running TVHeadEnd? I have, and it's the most reliable and feature-rich PVR I've ever used.

Apologies for resurrecting an old thread, but I'm also seeing temperature dependence of the magnitude of the B field returned by my Sense Hat. In my case the relationship is negative with a gradient of about -1 micro Tesla per degree Celcius, so I might be missing something. I'm reading from the RTI...