The magnetometer in your phone is a MEMS sensor which measures mechanical deflection of a current-carrying element. The deflection is caused by the Lorentz Force, i.e. force induced by an electron current flow in a magnetic field (in this case, the earth's magnetic field).[1] The magnetometer in the linked article senses (EDIT: corrected, hopefully) oscillation in the magnetic field of protons, a result of Larmor Precession[2]. Remarkably, the oscillation frequency is proportional to the ambient magnetic field strength, and the frequency is in the audible range. The circuit works by rotating protons in the fluid so that their magnetic axis align, this results in a synchronised bulk magnetic field oscillation that is large enough to be sensed by a simple tuned amplifier circuit.[3]
Further, the magnetometer in your phone is a 3-axis device that measures the orientation of the magnetic field, whereas the magnetometer in the linked article detects only the strength of the magnetic field (in fact, is tuned to detect only a single strength/precession frequency).
The sensitivity
When I play with phypbox [1] there is a sensitivity in the µT range.
From the web page [2] the device build has a 0.1 nT resolution and 50 ppm absolute accuracy.
Certainly banned enough that you can't listen to ATC playback anywhere online. I think in practice you can use an air band radio at home (not sure how anyone would know if you were anyway).
You need to have pretty tight supply chains if you’re going to support warranty claims on something as consumable as disks. I don’t know who supplies their HDD and SSDs, but you’d want the relationship and traceability to be pretty robust.
Syno have always been a software company first, a hardware company second, and a storage media company last. It makes sense to try and control the full vertical, but they just don’t have enough clout to compete against the big enterprise companies.
I honestly believe the disk whitelisting thing was part of an attempt to overvalue the company in preparation for a sale.
That seems like a lot of effort - is there no ability to boot a custom thumb drive that loads something like an SSH terminal, or dummy display for VNC?
The problem is not getting TrueNAS on a disk. You can do it externally, but you need to disable the on board flash storage and change the boot order from the BIOS.
That box is "just" an I/O optimized PC which can boot without a GPU.
Older hardware with Intel processors have an iGPU on board. You can use the HDMI output on these directly.
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