Ratio test

Impulse test

Short circuit test

Open circuit test

To reduce the constant losses

To reduce electric interference

To increase the quality of sound

To increase the efficiency of receivers

Minimizes copper use

Reduces hysteresis loss

Reduces eddy current loss

Reduces the space for core

Silica gel

Sodium chloride

Ammonium chloride

Charcoal and salt mixture

More losses

Heavier in weight

Poor voltage regulation

Cannot isolate the secondary winding