Which core! Did you mean electronics? Please don't limit yourself in vellore or any particular place. Try everywhere like chennai, coimbatore, Bangalore, hyderabad, Pune, . .etc,. if you really want to get into a core company.
Best of luck
SIJO Sam
Being a fresher you need to have some good knowledge in basics electronics concept. Since core companies won't recruit more as IT companies do. They will select only few candidates, so you should be strong enough to crack aptitude and interviews.
SIJO Sam
Usually core companies recruit very less through campus unless its a reputed college. After college you'll get very few chances with much competition. So don't even miss a small chances also. Prepare well.
Best of luck