Hi
ECE from PEC wud be a much better option than Mech from DCE. Graduates in Electronics Engineering have opportunities in Government and private companies for installation, operation and maintenance of electronics equipments and systems. Defence, space and other large research organisations employ electronics engineers in design and development of complex devices and systems for signal processing and telecommunication. Industries involved in design and fabrication of devices, integrated circuits, embedded systems, electronic equipments etc have also provide large scale placements for engineers with this specilisation. Installation and maintenance of electronic equipments used for health care in hospitals, equipments & systems for instrumentation and control in process industries automation systems of assembly line in production industries, etc are also handled by electronics engineers.

An electronics engineer can be employed in the public and private sector industries and organizations such as the Indian Telephone Industries, MTNL, National Physical Laboratories, AIR, Civil aviation, and the police wireless departments. 
Electronics engineers are also absorbed into the entertainment transmission industry, research establishments, and defense. They can also take up teaching and research in one of the many engineering colleges in India or abroad.
Mech from DCE is also gud bt ECE from PEC promises better prospects as compared to mech. DCE and PEC are at par in terms of placement but ece is paid more than mechanical.