I was slightly concerned about the contact resistance of the 10->8 mm brass compression fittings in my induction heaters tank circuit. Out of curiosity I measured the resistances in my tank circuit. I thought I’d make this small post about how to measure very low resistances. This might be fairly obvious to someone but it still bears mentioning. The easiest way to measure very low resistance is by passing a much […]

I’m currently building an induction heater. I’ve already built one controller based on an analog PLL so this time I decided to go all digital and use an ARM Cortex-M4 microcontroller (STM32F303). For this I needed to implement a digital phase-locked loop running on the MCU. Principle An ADPLL is basically an analog phase-locked loop but implemented in software. You take the phase difference between a reference signal (the one […]