noun
dust core
Technical term in electronics and magnetics: a magnetic core made by compressing powdered magnetic material, often used in inductors and transformers.
圧粉磁心は高周波回路でよく使われる。
Dust cores are often used in high-frequency circuits.
Compound of 圧粉 (appun, 'compressed powder') + 磁心 (jishin, 'magnetic core'). The reading あっぷんじしん reflects standard on'yomi for the kanji.