Feedback refers to a core concept in circuit design and control theory, used to stabilize amplifiers and control system ...

Editors’ Choice 2025 turntables show prices are up and cheap decks still disappoint. Choosing a long-term table now takes more thought—but pays off in music.

CES 2026 is just around the corner and we will be there again. Here, we look back at our 2025 coverage, which was very ...

Abstract: Electrical impedance matching of ultrasonic transducers is important in optimizing the energy consumption as well as guaranteeing equipment safety for ultrasonic systems in both laboratories ...

Abstract: Impedance matching is a common issue in a wireless power transfer (WPT) system. This paper summarizes impedance matching methods reported in the literature and gives a theoretical analysis ...

Skin-electrode impedance was measured for four different types of conventional electrocardiographic electrodes applied under different conditions. All types of contacts were frequency dependent; a ...