H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
H03F1/08—Modifications of amplifiers to reduce detrimental influences of internal impedances of amplifying elements
H03F1/18—Modifications of amplifiers to reduce detrimental influences of internal impedances of amplifying elements by use of distributed coupling, i.e. distributed amplifiers
H03F1/20—Modifications of amplifiers to reduce detrimental influences of internal impedances of amplifying elements by use of distributed coupling, i.e. distributed amplifiers in discharge-tube amplifiers