Notes tagged ‘measurement’

Quick and Dirty B–H Plots

While building solenoids, I needed a way to quickly judge the magnetic properties of some unknown steel. A simple analogue hall sensor IC works together with a controlled current source for the coil to drive a XY plotter (or oscilloscope in XY mode) and create simple B–H plots.

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Thermocouple via Integrated Differential Amplifier

Recently, I needed a simple temperature switch which could withstand 400 °C. A thermocouple can easily manage this but its generated voltage is unpleasantly small. However, it turns out that a ATTiny216A’s integrated differential amplifier is absolutely sufficient for a, albeit not very accurate, measurement. Enough to determine if something is hot or not, at least.

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Milliohm Meter Test Fuchs MOM1

While restoring a milliohm meter made by Test Fuchs I could not find any information about, I traced its schematic. It can be found here in case anyone has the same instrument.