@tpetar can you justify what you said "GSM bill maded by SMS usage will be lower then electricity" ? it will be good for my project.
- What is price of one SMS ? I think SMS is not free, someone will pay these SMSs.
- How many SMS this device make in one month cycle ?
- Monthly price for device usage (SMS/Month) x SMS price.
- What happen when jammer is turned On or there is no GSM network ? How will you pay and how much ? Before paying you should receive status of counter and based on that you will get bill, but how you will get bill when they cant read your counter status?
Plus on this, I didnt mention clonning possibility of SIM cards and IMEI number which can be used to send fake SMS with smaller counters.
Maybe its planned to send only one SMS on last day in month, but what will happen with GSM network and provider servers if receiving and relaying huge number of SMS? Should I say that some places have milions or more of counters.
Problem is in base of concept and its logical.
I must say, its my thinking, this project and concept dont have practical future, but its good for practice and getting skills in electronics.
Better read about newer digital counting devices with capabilities of reading and management over mains wires and mains voltage, and focus your time and energy on this.
;-)