Much of this new year has been spent working on improving the calibration of AMOS's magnetometers. The calibration jig discussed in the last blog entry has been completed and tested out, and seemed to work pretty well! Next up was an apparatus for performing a simple temperature calibration of the magnetometer sensors. To keep the temperature calibrator as simple as possible, it was decided to just put a small heater and fan into a small box with the device under test, and have everything hooked up to the Raspberry Pi on AMOS. Fortunately I had nearly all of the required parts already on hand: a spare heater cartridge from the 3D printer, an old heatsink and 12 V fan from a decades-ago junked desktop PC (never throw anything out, you might need it someday!!! 😜), an electronics enclosure box that had previously been embedded in the failed foam hull (see https://readerforgmail.blogspot.com/2020/11/breaking-mold.html), a DC-DC converter, and a 4-port relay (with just one fried port from the previous paddle experiments: https://readerforgmail.blogspot.com/2020/08/paddle-test-take-2.html). I did need to buy a 24 V supply though to power the heater.
Here's a pic of the interior of the temperature calibration box once it was all put together: