<p>Pengujian kompatibilitas elektromagnetik pada inkubator bayi berdasarkan standar CISPR 11 merupakan pengukuran medan elektromagnetik secara <em>Far Field</em>. Metode pengukuran berdasar CISPR 11 tersebut belum menggambarkan besaran paparan elektromagnetik yang diterima oleh bayi pada jarak dekat. Penelitian ini dilakukan sebagai pengembangan metode CISPR 11 pada pengukuran medan elektrik dengan melakukan pemetaan sebaran medan elektrik. Metode penelitian yang digunakan adalah metode ekperimen dengan menggunakan teknik<em> pusposive sampling</em> dalam pemilihan inkubator bayi. Radiasi elektromagnetik inkubator diukur berdasarkan standar pengujian CISPR 11 dan dilakukan pengembangan metode pengukuran dengan melakukan pengukuran <em>near field planar system</em> untuk pemetaan medan elektromagnetik. Pemetaan tersebut digabungkan dengan gambar simulasi posisi bayi saat diletakkan di inkubator kemudian dianalisis perkiraan intensitas medan yang sampai pada bagian otak bayi. Dari sampel yang dipakai terdapat paparan medan elektromagnetik tertinggi di 3 frekuensi yaitu 121, 132, 221 MHz. Pola sebaran medan elektrik yang dihasilkan dari setiap frekuensi berbeda-beda dan masing-masing frekuensi memiliki area yang memiliki medan elektrik tertinggi yang berpotensi mempengaruhi bayi terutama organ vital yang berada pada area tersebut. Metode pemetaan ini dapat digunakan sebagai pengembangan metode pengukuran radiasi elektromagnetik pada inkubator bayi, terutama untuk mengetahui sebaran medan elektrik diatas permukaan matras inkubator.</p>

Existing WiFi mesh networks are usually implemented on high-end or PC grade platforms. However, the open source community has been recently developing a unique mesh network library targeted for the low-cost and resource limited ESP8266 platform. The so called painlessMesh library enables two or more ESP8266 modules to self-configure and to form a WiFi mesh network. This might open up new potential for the ESP8266 to be used in wider application areas. The library is in an early development stage and not much is known about its performance. Therefore, this paper aims to evaluate to what extent the ESP8266 painlessMesh network can perform, in terms of one-way delay and data rate. Measurements showed that a 2-node network has a delay of 2.49 ms. A network consisting of higher number of nodes tends to have an increased network delay even for the same hop distance. Meanwhile, data rate measurements showed that for the case of 10-byte payload a node can receive up to 461 messages/sec. Whereas for payload of 4400 bytes, the node can receive up to 28 messages/sec. Furthermore, it can be reported that payload greater than 4400 bytes starts causing incomplete and erroneous messages.

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LED lighting market share shows an ever increasing trend. This is driven by some of the LED advantages, such as higher efficiency, wide range of colors, and longer lifetime. LED is a DC device, and to power it from AC supply, like in household or street lightings, a driver is required to convert AC to DC supply. In addition, LED driver is preferred to operate in constant current mode in order to avoid LED thermal runaway. Also the driver has to have high efficiency, low THD (total harmonic distortion), and comply with electromagnetic emission limits. In this paper, a prototype of primary-side-regulated AC-DC flyback LED driver has been implemented. It has a constant output current of 0.990A  0.012A across the output voltage 15.59V – 42.80V. Measurement results show that the achieved efficiency is up to 88.55%, current harmonics comply with IEC 61000-3-2, and conducted emission levels comply with CISPR 15.