How to make Balance Recharge card Pin number

Its very simple process. In each and every front side of RC card you can find Serial No and ... How do Telcos generate recharge cards? How are SIM cards made? How can I recharge (datapack, roaming card, talktime etc.) an indian cell phone number ...I have wondered about this quite a lot of times and I'm trying to attempt this problem with my ... Answer Wiki ... A mobile recharge card have a hidden pin no which can be used to fill some amount. ... If you find an answer or an algorithm to generate those numbers... let us know... those algorithms are the base of security to ...