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Perbandingan Efisiensi Daya Penguat Audio Kelas AB dengan Penguat Audio Kelas D untuk Keperluan Sound System Lapangan

Kharis, Muhamad, Prastiyanto, Dhidik, Suryono, Suryono

Jurnal Teknik Elektro Vol 10, No 2 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

Class AB audio amplifiers are commonly used but the efficiency is 50%. While the efficiency of class D audio amplifiers is 90% but are rarely used. The purpose of this research is to know how much the power efficiency of field sound system between 1000 watts class AB amplifier and 900 watts class D amplifier. This study is a comparative study that compares different variables with the same sample. The results of power efficiency are obtained from the percentage comparison between the output power and the input power of each audio amplifier. The power efficiency of class D audio amplifiers with IRS D900 type larger than class AB audio amplifiers with Apex B500 type. The efficiency value of class D audio amplifiers at the highest output power reaches 87% while class AB audio amplifiers are only 73%.

Implementasi Algoritma Kalkulasi Interupsi pada Rancang Bangun Tachometer Digital

Maria, Putut Son, Susianti, Elva

Jurnal Teknik Elektro Vol 10, No 2 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

Tachometer is an important tool for measuring the rotational speed of electro-mechanical machines and other rotating objects. In a closed-loop system, it should have a mechanism by which sensory instruments must be able to produce and deliver feedback values that can be fetched by the controller. Most commercial tachometers do not have such data communication features, making it difficult to be employed in closed loop systems. This study aims to develop a tachometer which is programmed using calculation on interrupt-based algorithm and has data communication capabilities as well. The algorithm was designed over the minimum features of a microcontroller chip, namely a timer and interrupt. The proposed algorithm that was tested on the prototype results good performance for the typical electro-mechanical machines with a measurement error range between 0.1 and 1.2%. The equation for the calculation of rotation per minute (rpm) has also been revised to provide a more valid formula.

Rancang Bangun Antena Bowtie pada Video Sender sebagai Pemancar TV Streaming

Bestari, Nabila Shaffa, Wagyana, Agus

Jurnal Teknik Elektro Vol 10, No 2 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

A streaming television usually broadcasted through internet and can be watched on computer or mobile phone. However it can also be seen through television using video sender as the transmitter. To transmit it, of course, a suitable antenna is needed, in this case a bowtie antenna is selected. This research describe the design of a bowtie antenna that will be used as a transmitter antenna on a video sender. This bowtie antenna is designed by using an aluminum plate works on frequency of 655 MHz and has a return loss value of -21.127 dB, VSWR 1.192, 5.11 dB gain and bi-directional radiation pattern. The analysis process is carried out by analyzing the data taken from the audio and video results received in television as well as data from the measurement of signal strength captured by Register Transfer Level Software Define Radio (RTL SDR) and dipole antennas. Measurement results will be displayed in the sdrSharp software. The results of this measurement will be associated with field strength which is related to television signals. This bowtie antenna can transmit audio and video up to 30 m and has an average field strength value in Line of Sight (LOS) conditions of 120.3208 dBμV / m and at Non Line of Sight (NLOS) conditions of 123.5014 dBμV / m which is in accordance with the field strength standard in Indonesia that regulated in Perkominfo No. 31 Tahun 2014 which is above 70 dBμV / m in band V.

Smart Riders 3D Sebagai Game Pengenalan Rambu Lalu Lintas Berbasis Android

Sulastianingsih, Febri, Kartono, R.

Jurnal Teknik Elektro Vol 10, No 2 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

Android smartphone, one of the entertainment media that is used by many people for games. Besides being an entertainment media, games can be used as educational media, such as the introduction of traffic signs. Knowledge of traffic signs on motorists influences the occurrence of traffic accidents. Therefore, the introduction of traffic signs is one of the efforts in controlling traffic. This is because knowledge of traffic signs is currently lacking. In this study, it will present the making of a Smart Rider application that aims to introduce traffic signs to prospective drivers and drivers of motorized vehicles. The software development method used is Waterfall, which includes communication, planning, modeling, construction and deployment. Application testing uses material testing, functionality, usability and portability. Usability testing is done by media experts and users. Users in this study were taken from Kebumen Vocational High School 1 students. From the results of testing the application as a whole, shows that the application has a good function. The test results can be seen from the material test reaching 94.4%, the user response reached 78.74%, and the results of testing by media experts reached 87.5%. Thus, the Smart Rider application is declared feasible to be used as a game for introducing Android-based traffic signs.

Analisis Metode Certainty Factor pada Sistem Pakar Diagnosa Penyakit THT

Setyaputri, Khairina Eka, Fadlil, Abdul, Sunardi, Sunardi

Jurnal Teknik Elektro Vol 10, No 1 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

There are two factors that cause a disease, called  Congenital and Acquired. Congenital refers to a disease a person is born with, while Acquired refers to a disease acquired after a person was born such as infection, trauma, and neoplasm. The infected person will sometimes require information on the disease before going to the doctor or a hospital. Such information may be found from a system which receives input on the symptoms and gives a clear information on the corresponding disease. This may be achieved via a system of experts, in which the expert refers to an ENT (Ear, Nose, and Throat) specialist. Such information is hoped to provide a solution on the disease. The system of ENT specialists designed and research in this paper used the certainty factor method. The method will overcome the uncertainty in decision making depending on the symptoms described by the user. This paper is successfully applied certainty factor method used as an instrument of decision making in the system of ENT specialists. The system is web-based, enabling the user to access and choose the symptoms of the disease as well as acquiring information on ENT diseases  easly.

Prototype Mesin Pengantar Barang Otomatis Menggunakan Load Cell Berbasis Robot Line Follower

Susilo, Dwi Budi, Wibawanto, Hari, Mulwinda, Anggraini

Jurnal Teknik Elektro Vol 10, No 1 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

Overloaded condition in the product porter like hand pallet, hand stacker, forclift, and etc, can causes damage and terrible accident in the machine operator. This research aim to build a prototype of porter machine that can prevent overloaded condition through the reading of load cell and photo diode sensor to guide the line follower direction. Research and development methods are used with the systematic writing are background of study and problems, prototype design and validation, testing, taking and analysis of the data. Output of the research is a prototype of porter machine using load cell sensor based on line follower robot. The Result of the load cell reading is compared to SF-400 weigher, and found the difference amount 0.117%. The load testing data of automatic moving trigger is 1 gram until 2999 gram. The Overload condition warning is active while the load is more than 3000 gram. The data reading of the photo diode on the black line is running succesfully, however on the white line with orange color is found some error.

Optimalisasi Stand-Alone Photovoltaic System dengan Implementasi Algoritma P&O-Fuzzy MPPT

Juniyanto, Dimas, Andrasto, Tatyantoro, Suryono, Suryono

Jurnal Teknik Elektro Vol 10, No 1 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

The need for electrical energy continues to increase every time. Concerns about the depletion of fossil energy reserves encourage the acceleration of the development of renewable energy use. One of renewable energy is the solar energy. Due to the irreversible irradiation conditions, it takes controls to keep the solar panels maximum power. The most widely in Maximum Power Point Tracking (MMPT) is Perturb Algorithm and Observe (P&O) but P&O Algorithm has deficiency of oscillations when steady state and MPP trace errors when irradiation changes rapidly. In this paper proposed P & O-Fuzzy algorithm is a modification of conventional P & O to improve the efficiency of solar panels. This research uses Matlab for simulation and hardware implementation using microcontroller Arduino Uno and buck converter topology. The result of simulation and hardware implementation, conventional P & O has an average efficiency of 85.03% while MPPT modification with P & O-Fuzzy algorithm can improve MPP tracking efficiency with 89.67%.

Rancang Bangun Alat Monitoring Pergerakan Objek pada Ruangan Menggunakan Modul RCWL 0516

Aini, Qurotul, Rahardja, Untung, Madiistriyatno, Harries, Fuad, Azharul

Jurnal Teknik Elektro Vol 10, No 1 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

Nowdays, along with the  development of electronics and computers, the crime rate increases  rapidly.  today almost all systems and security tools are using electronic devices such as computers and  microcontrollers. Every electronic device always has weakness, such as camera needs the light to capture images, Passive InfraRed (PIR) sensor only has ability for human body temperature detection, Short Message Service (SMS) which its services depend on prepay credit and cellular operator signal range.  Based on the problem, a radio-based doppler radar detection tool was developed using RCWL 0516 module. In this research will be discussed the use of RCWL 0516 sensor as main module to detect the movement of the object by measuring the microwave wave value that displayed on the user gadget by using Blynk application. The digital communication is used and implemented on Arduino Uno microcontroller. The data is sent and will be displayed on the gadget through Blynk application in the form of graph in real time and connect to the internet using ESP8266 as a connection receiver. The results obtained that the RCWL 0516 module has a better accuracy level in detecting movement than other motion detection sensors such as PIR sensors and ultrasonic sensors.

Identifikasi Bukti Digital WhatsApp pada Sistem Operasi Proprietary Menggunakan Live Forensics

Riadi, Imam, Sunardi, Sunardi, Rauli, Muhamad Ermansyah

Jurnal Teknik Elektro Vol 10, No 1 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

Rapid development of computer technology is also accompanied with increasing of cybercrime. One of the most common crimes is fraud case in the online shop. This crime  abuses Whatapps, one of the most popular Instant Messenger (IM) applications.  WhatsApp is one of the IM applications that can be used on computers, especially on windows 8.1 operating system. All applications running on the computer leave data and information on Random Access Memory (RAM). The data and information that exist in RAM can be obtained using digital forensic technique calledLive Forensics. Live forensics can be used when the computer is running and connected to the  network. This research aims to find digital evidence related to online shop fraud case. The digital evidence can be obtained using one of the forensic tools FTK Imager. FTK Imager can retrieve and analyze data and information on RAM. The results obtained in this research is the content of WhatsApp conversations that can be used as digital evidence to reveala fraud in the online shop.

Analisis Karakteristik Elektrik Bentuk Geometri Jalur PCB Menggunakan Pendekatan Finite Element

Maria, Putut Son, Susianti, Elva

Jurnal Teknik Elektro Vol 10, No 1 (2018): Jurnal Teknik Elektro
Publisher : Jurusan Teknik Elektro, Fakultas Teknik, Universitas Negeri Semarang

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Abstract

Some Electronics Computer Aided Design (ECAD) softwares have provided several track shapes to design a Printed Circuit Board (PCB), such as right angle, rounded and trapezoidal. However, it is quite difficult to find scientific literature that can be used as a guide which explains and compiles directly about each character of the geometry. This study aims to analyze and to observe the electrical characteristics of the geometry shape on the Printed Circuit Board (PCB) path by using the finite element method. Each PCB path shape is modeled according to its geometry and physical properties, then calculated for its electrical quantity and be observed for its performance at given current. Simulation and numerical calculations showed that the shape of trapezoidal and rounded geometry have lower resistance and planar inductance of 6.8% and 7.39% respectively than the right angle shape.