[¦dəb·əl ¦am·plə‚tüd ¦mäj·ə‚lā·shən ′məl·tə‚plī·ər] (electronics) A multiplier in which one variable is amplitude-modulated by a carrier, and the modulated signal is again amplitude-modulated by the other variable; the resulting double-modulated signal is applied to a balanced demodulator to obtain the product of the two variables.