NARIT) has joined the BIMA Project as the main partner. This project aims to build an open-database of eclipsing binary minima and to establish the orbital period of each system and its variations. The project is conducted on the basis of multisite monitoring observations of eclipsing binaries with magnitudes less than 19 mag. Differential photometry methods have been applied throughout the observations. Data reduction was performed using IRAF. The observations were carried out in BVRI bands using three different small telescopes situated in Indonesia, Thailand, and Chile. Computer programs have been developed for calculating the time of minima. To date, more than 140 eclipsing binaries have been observed. From them 71 minima have been determined. We present and discuss the O-C diagrams for some eclipsing binary systems.

Low resolution spectra of Nova Delphini 2013 (V339 Del) in the optical range have been obtained at Bosscha Observatory, Indonesia during its maximum light (V = 4.3). Spectra were observed from August 16 to 27, 2013. The GAO-ITB RTS 20.3 cm telescope, and SBIG DSS-7 spectrograph and SBIG ST-7 XE as the detector have been employed throughout the observations. The spectra show P-Cygni profiles in Balmer, NaI'D' and Fe II lines, from which we determined shell expansion velocities of 1421.66±39.18 km/s, 1227.54±21.57 km/s and 1402.86 km/s, respectively. Our spectroscopic observations followed the spectral evolution of V339 Del from the pre-maximum phase to early Orion phase. The characteristics of the nova Delphini 2013 resembles those of Fe II-type novae.

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