<![CDATA[ABSTRAKPenelitian ini membahas mengenai penerima gelombang extremely low frequency (ELF) untuk pengolahan akuisisi data gempa bumi. Penerima ELF dirancang menggunakan operational amplifier (Op-Amp) dengan masukan takmembalik. Sinyal yang diterima oleh antena diteruskan ke penerima ELF yang terdiri dari preamplifier dan amplifier untuk proses penguatan, serta filter aktif orde 2 untuk menekan sinyal di atas frekuensi cut-off sebesar 50Hz. Karakterisasi penerima ELF dilakukan dengan mengamati perbandingan level tegangan sinyal keluaran terhadap level tegangan sinyal masukan, sensitivitas, serta bentuk sinyal keluaran dari penerima ELF dalam domain waktu. Hasil simulasi menunjukkan bahwa penerima ELF menghasilkan penguatan sebesar 60,8dB dengan sensitifitas tinggi untuk level sinyal masukan di bawah -30dB yang mampu memenuhi level sinyal untuk pengolahan akuisisi data.Kata kunci: extremely low frequency, penerima ELF, operational amplifier, filter aktif, gempa bumi ABSTRACTThis research presents extremely low frequency (ELF) receiver for earthquake data acquisition processing. The ELF receiver is designed based on non-inverting operational amplifier (Op-Amp). The signal received by the antenna is fed into ELF receiver which consists of preamplifier and amplifier for amplification, and second order active filter to suppress unwanted signal above the cut-off frequency of 50Hz. Characterization of ELF receiver is performed by observing the comparison of the level output signal to level input signal, sensitivity, and ELF receiver signal output in time domain. The simulation results show that the ELF receiver has gain of 60.8dB with high sensitivity for low level input signals below -30dB that is able to meet signal level for data acquisition processing.Keywords: extremely low frequency, ELF receiver, operational amplifier, active filter, earthquake]]>
