Dear Jeetendra,
About this 1.Pay Scale : Rs. PB-3 Rs. 15600 - 39100 Grade Pay Rs. 5400......?
and
About 2.Pay Scale : Rs.15285-670-18635-705-36965
If the gross earnings(not net pay) is more than 15285 and lessthan 18635 then increment Rs670 every year(period depends upon the policy of the government department)
similarly
If the gross earnings > 18636 and < 36965 then increment Rs. 705 according to the period(Quar/half/year)