The Signals are dependant on atomic clocks and synchronised Using the worldwide program of clocks that aid Coordinated Universal Time. India's time zone is based about the 82.5°E meridian, which passes through Mirzapur. The 50 %-hour offset was chosen to keep the time near to the mean solar time across https://currenttimeinindia53075.wikirecognition.com/2461205/not_known_facts_about_pst_to_ist