... low saturation magnetic induction. Fe-Ni Soft Magnetic Alloy (Permalloy) Core 1. Material Grade: 1J50,1J79, 1J85 2. Features and ... precision current transformer, magnetic amplifier, power transformer, choke, pulse transformer, change polarity pulse transformer, DC voltage converter, magnetic modulator, constant inductance ... actual usage requirements. Fe-Ni Soft Magnetic Alloy (Permalloy) Core