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Global Positioning System (GPS) is widely used in a variety of fields, including aircraft applications and rockets where speeds exceed standards. Signal simulators, which are relatively expensive, are required to test commercial GPS devices and GPS signal processing methods. The methodology for verifying GPS receiver specifications using a Software Defined Radio (SDR)-based simulator is described in this paper. Simulator tests are run in both static and dynamic modes. The test findings demonstrate that the system can measure altitude and speed, but only up to 50 km and 500 m/s, respectively, according to commercial GPS specifications. This simulator system can be used to evaluate future GPS processing algorithms in highly dynamic environments.

This study aimed to explore the needs for developing materials to improve Arabic writing skills at University of Darussalam Gontor (UNIDA Gontor). The study utilized the preliminary stage of a research and development research design, aiming to address current deficiencies in instructional materials. The primary objective was to analyse the requirements of both students and lecturers. The data were collected using a combination of observation, documentation analysis, and questionnaires. The documentation analysis showed UNIDA Gontor's dedication to multilingual competency, ensuring focused and comprehensive Arabic writing instruction. The results of survey questionnaire revealed the existence of variations in instructional material, which caused disparity in how materials were understood. The data also demonstrated that there was a need for alignment of teaching materials with UNIDA's language standards. This research summarized the needs of both lecturers and students for developing Arabic teaching materials that met the requirements of the university and enhanced students’ proficiency in Arabic writing.

At this time the research related to the effect of magnetostriction for underwater applications is still limited. Acoustic or sound waves are more easily propagated underwater than electromagnetic waves or light. An acoustic wave or sound can be generated by utilizing the magnetostriction effect, where this effect occurs when a rod of ferromagnetic material such as iron or nickel is magnetized and interacts with another magnetic field, resulting in vibration of the metal rod. This research aims to design and realize a magnetostriction generator as an acoustic wave generator at a frequency of 1 to 10 kHz for underwater applications, consisting of: a tuned LC oscillator circuit, and a ferromagnetic metal rod which is magnetized using a dc voltage. The results of measurements and testing of the magnetostriction generator show: (1) if it is equipped with a membrane, can work to emit an acoustic wave or sound at a frequency of ± 8.62 kHz in the air up to a distance of 15 cm without distortion with an average amplitude decrease of ± 0.648 dB for each the distance increased by 1 cm, and (2) if equipped with a membrane and enclosed in a waterproof casing, capable of transmitting the acoustic waves at a frequency of ± 8.31 kHz underwater up to a distance of 7 cm without distortion with an average amplitude decrease of ± 4.217 dB for each the distance up 1 cm. Overall the magnetostriction generator designed can work to generate and transmit the acoustic waves or sound underwater, as expected.

As one of the universities in Indonesia that focuses on teaching Arabic, University of Darussalam Gontor requires all its students to use the language well, especially Arabic in various scientific fields. But the problem faced is the unavailability of special textbooks for Agro-industrial Technology study programs. This research is intended to design Arabic language teaching materials based on maharatu al-qira’ah in the Agro-industrial Technology Study Program at the University of Darussalam Gontor using the Research & Development methodology. The results of this research are the Arabic textbook Maharatu al-qira’ah improves the ability of students in Arabic material, especially in reading skills.

A Radio detection and ranging (radar) is used to detect and track objects in the air and on land, one type of the radar that is known is a passive radar. The radio direction finder (RDF) as an element of a passive radar is used to determine the direction angle, based on a radio waves that emitted by an object. The purpose of this study is to produce a RDF that works on HF bands as passive radar elements. In this study a RDF has been produced, which consists: a receive antenna in the form of a dipole λ/8 and a yagi 5 elements with horizontal polarization, a tuning circuit, an AM signal detector, an audio amplifier, and equipped with a level signal display in the form of a S meter and a loudspeaker. The test results for outside and inside the room at a certain time, the RDF can detect the angle of direction of horizontal plane of an object or AM transmitter from 0° to 360° in the frequency range between 4.02 to 10.76 MHz. The results of detecting the angle of direction of an object or a transmitting radio waves in the HF band, in the form of a signal level are then plotted on the polar diagram of the horizontal plane, and the sound can be heard through the loudspeaker. Furthermore, the results of this study can be used for the development of a RDF independently, and its implementation in the passive radar.

ABSTRAK Ketika suatu pesawat terbang mengalami kecelakaan terjatuh ke dalam air, maka lokasi keberadaannya dapat dideteksi oleh alat yang disebut receiver beacon black box locator acoustic (pingers receiver). Pingers receiver berfungsi untuk menerima sinyal dengan frekuensi 37,5 kHz ± 1 kHz dari pingers transmitter atau Underwater Locator Beacon (ULB) yang berada pada black box pesawat. Dalam penelitian ini dibuat perancangan pingers receiver yang tersusun dari rangkaian Band Pass Filter (BPF), detektor selubung, penguat audio, dan loud speaker. Frekuensi sinyal 37,5 kHz ± 1 kHz yang dikirim oleh pingers transmitter akan diterima oleh pingers receiver, dimana tahap pertama melewati rangkaian Band Pass Filter (BPF) selanjutnya sinyal akan dideteksi oleh detektor selubung untuk mengambil kembali sinyal informasi yang berupa sinyal pulsa dengan lebar pulsa 10 milidetik dan interval 1 detik sebagai sinyal pingers yang nantinya mampu didengar oleh telinga manusia. Berdasarkan perancangan yang telah dibuat, output sinyal yang dihasilkan oleh prototipe pingers receiver tersebut memiliki lebar pulsa 14 milidetik dengan interval 1 detik. Kata kunci: pingers receiver, band pass filter (BPF), detektor selubung, loud speaker. ABSTRACT When an aircraft caught in an accident and crashes into the water, its location can be detected using a device called a receiver beacon black box locator acoustic (pingers receiver). The pingers receiver functioned as a reciever signal with 37,5 kHz ± 1 kHz frequency from trnasmitter pingers or Underwater Locator Beacon (ULB) which is on air plane black blox. In this research made design pingers receiver composed of a series of Band Pass Filter (BPF), envelope detector, audio amplifier, and loud speaker. The signal of 37,5 kHz ± 1 kHz frequency sent by pingers transmitter will bereceived by pingers receiver, after which the signal will be processed by the Band Pass Filter (BPF) circuit before being detected by envelope detector for take back the signal information which like pulse signal with 10ms width and 1 second interval as pingers signal tha can be to be heard by human ear. Based on the design that was made, the signal ouput generated by the prototype has a 14 ms width with 1 second interval. Keywords: pingers receiver, band pass filter (BPF), envelope detector, loud speaker.

ABSTRAK Dalam pencarian suatu obyek di bawah air dibutuhkan metode khusus yang digunakan dengan suara (gelombang akustik), dikarenakan suara dapat merambat dalam jarak jauh pada air. Frekuensi yang dapat diterima oleh SONAR bergantung pada alat penerima yang mengubah suara menjadi sinyal elektrik agar dapat mendeteksi frekuensi, alat penerima ini dinamakan hydrophone. Dalam penelitian ini dibuat perancangan prototipe hydrophone, yang tersusun dari transducer (akustik-elektrik) dan penguat. Berdasarkan perancangan yang telah dibuat prototipe hydrophone mampu menerima (menangkap) gelombang akustik pada range frekuensi 100 Hz – 60 kHz, dengan menggunakan transducer berupa condenser microphone yang diselimuti oleh bahan karet tipis. Prototipe hydrophone tanpa pelindung anti air, dengan pelindung anti air, dan di dalam air dapat menerima (menangkap) gelombang akustik. Kata Kunci: SONAR, hydrophone, transducer ABSTRACT In finding an object beneath the water there has to be a specific method used sound (accoustic wave) in keeping with it can apread in long distance in the depth of water. The frequency which can be detected by sonar system, counts on the receiver which converts sound to electric signal so that the frequency can be detected and it is called hydrophone. In this research, there is hydrophone prototype which piled up by tranducer and amplifier. Based on the trial, hydrophone prototype can detect accoustic wave in range 100 Hz-60 kHz with the condensor microphone as a transducer covered of thin rubber material. Besides, hydrophone prototype with or without water resistor is still capable to detect acoustic wave. Keywords: SONAR, hydrophone, transducer

ABSTRAK Pingers transmitter berfungsi untuk memancarkan sinyal atau getaran pulsa akustik pada black box. Frekuensi sinyal yang dipancarkan sebesar 37,5 kHz yang dimodulasikan oleh pulsa dengan durasi 10 ms setiap interval 1 second. Modulasi yang digunakan adalah modulasi on off keying. Dalam penelitian ini dibuat perancangan pingers transmitter yang tersusun atas rangkaian osilator, timer, inverter, switch dan rangkaian amplifier. Frekuensi 37,5 kHz tersebut dibangkitkan oleh rangkaian osilator colpitts, sedangkan lebar pulsa dengan durasi 10 ms dan pengulangan pulsa setiap interval 1 second dibangkitkan oleh rangkaian timer. Berdasarkan perancangan yang telah dibuat, output sinyal yang dihasilkan oleh prototipe pingers transmitter tersebut sebesar 37,69 kHz dengan lebar pulsa 9,8 ms setiap interval 1 second. Kata kunci: Black box, pingers transmitter, on off keying. ABSTRACT Pingers transmitter is used to emits a signal or pulse of acoustic vibrations in black box. The frequency of the transmitted signal is 37.5 kHz which is modulated by pulses with a duration of 10 ms every interval 1 second. The modulation that used this research is on off keying modulation. In this research, made the design of pingers transmitter which arrange of the oscillator circuit,timer, inverter, switch, and amplifier circuit. The 37.5 kHz frequency is generated by the colpitts oscillator circuit, while the pulse width with a duration of 10 ms,and each pulse repetition interval of 1 second generated by timer circuit. Based on the design that have made, signal output from the pingers transmitter prototype is 37.69 kHz, with the pulse width 9.8 ms every 1 second interval. Keywords: Black box, pingers transmitter, on off keying.

ABSTRAK Dalam suatu sistem komunikasi penggunaan rangkaian filter sangat penting. Salah satu cara untuk memudahkan dalam perancangan sebuah filter dilakukanlah teknik simulasi. Penelitian ini bertujuan untuk merancang simulasi yang menghasilkan respon filter jenis chebyshev serta menghasilkan nilai komponen induktor (L) dan kapasitor (C) yang dibutuhkan untuk merangkai filter. Simulasi yang dirancang pada penelitian ini menggunakan Graphical User Interface (GUI). Dari simulasi yang dilakukan, didapatkan respon Chebyshev pada low pass filter, high pass filter, band pass filter, dan band stop filter sudah sesuai dengan input yang dimasukkan ke dalam parameter program dan sesuai dengan teori respon filter Chebyshev. Hasil Simulasi dari rangkaian band pass filter dan band stop filter dengan menggunakan Electronic Workbench (EWB), menunjukkan respon dengan pergeseran frekuensi sebesar 0,1 kHz lebih tinggi dari frekuensi yang diharapkan. Kata Kunci: filter, Chebyshev, band, respon frekuensi. ABSTRACTOn communication system using filter is very important. One way to simplify the design of filter undertaken a simulation technique. This research aims to design a simulation that generates the filter response of chebyshev and generate the value component of the inductor (L) and capacitor (C) that needed for constructing the filter. This Simulation using Graphical User Interface (GUI). From result simulation, response in low pass filter, high pass filter, band pass filter, band stop filter and is in compliance with the input entered into the program and in accordance with the theory of Chebyshev filter response. The simulation of the band pass filter and bands stop filter by using electronic workbench ( EWB ), show a response with shifts frequency of 0.1 khz higher than frequency expected. Keywords: filter, Chebyshev, band, frequency respons