I have a coil. I have a current => I have a magnetic field ! Wait, do I ?

A naive first approach

We received the coils denominated SDE1006A-681K. These are 680 µH inductance coils.

We roughly soldered two wires on each pole of the coil as you can see on the image below for very basic testing.

Next we needed to connect it to the IoT node. As a very basic montage for testing, we configured user button with polling on the IoT node to drive one of the GPIO pin we have on high when pressed.

We used a resistance to limit the current output. As we wanted a current of the ordre of the mA we used a resistance around 1 kΩ.… Read more