  This paper presents a detailed description of various subsystems of CALLISTO
solar radio spectrograph installed at the USO/PRL. In the front-end system, a
log periodic dipole antenna (LPDA) is designed for the frequency range of
40-900 MHz. In this paper LPDA design, its modifications, and simulation
results are presented. We also present some initial observations taken by
CALLISTO at Udaipur.
