Given a linear time-invariant

network, with input

and output

, then the well-known frequency scaling theorem states that multiplication of all

\´s and

\´s by some constant

is equivalent to changing the input to

and the output to

. We show here that when the multiplier is a time-varying function

, the equivalent result is to change the input from

to

and the output from

to

where

. Some illustrative examples are footnote[1]{given}. (1)In this correspondence

means

; but

are inverse functions.