Extensive Air Showers (EAS), initiated by Ultra-High-Energy Cosmic Rays (UHECRs), generate geo-synchrotron and geo-magnetic radiations and they are, also, the source of excess charge processes. In the frequency range of 10 to 100 MHz, coherent radiation is formed. Many experiments use the radio detection technique for studying EAS features. The Auger Engineering Radio Array (AERA), part of the Pierre Auger Observatory, uses hundreds of radio antennas working in the frequency range of 30 to 80 MHz to support the investigation of UHECRs together with the standard surface and fluorescence detectors. The AERA radio frequency range is significantly contaminated by the human-made and usually narrow-band Radio Frequency Interference (RFI), e.g., shortwave radio transmitters. The presence of RFIs in the detected signals increases the ratio of spurious triggers; in consequence, empty data inflate the databases. This study proposes replacing the currently used IIR-notch nonadaptive filter by the delayed version of the wellknown Least Mean Squares (LMS) algorithm, which offers crucial advantage adjustment. The current study implemented 32/64-stage Delay Least Mean Squares (DLMS) filters on cost-effective Cyclone® IV and Cyclone® V as non-canonical Finite Input Response (FIR) with a sufficient safety margin for a global clock being at least 20% higher than 200 MHz, which equals the ADC sampling frequency.