Before revision: The tuned radio frequency (TRF) receiver, one of the most popular radio receiver designs of the time, consisted of several radio frequency (RF) amplifier stages, followed by a detector and several audio amplifier stages.
After revision: tunedThe tuned radio frequency (TRF) receiver, one of the most popular radio receiver designs of the time, consisted of several radio frequency (RF) amplifier stages, followed by a detector and several audio amplifier stages.