Henry, [83]
Heterodyne, [181]
Hot-wire ammeter, [51]
Human voice, mechanism of, [152]
Hydrogen, action of in acid, [7];
atom of, [7]
Impedance, of coil, [136];
of condenser, [136];
of transformer, [195];
effect of iron core upon, [207];
matching of, [196]
Intermediate-frequency amplification, [242]
Inductance, defined, [83];
effect upon frequency, [100];
impedance of, [135];
mutual, [109];
of coils, [101];
self, [83];
table of values, [227];
unit of, [83];
variable, [108]
Induction, principle of, [208]
Inducto-meter, [109]