If you have technical anlaysis software like Amibroker or Metastock and EOD datafeed for them and ofcourse also know how to use them by writing scanners etc.
then in first few post I have given link to post by other users who have also shared the scanner code for NR7.
Otherwise, you can create your own system on excel sheet. Rather then jumping on all NSE stocks.. just pickup the price of Nifty-50 stocks from NSE site everyday, copy them in excel sheet.. After 7 days, you will have your own database. Use the formula given in the sheet at the start of this thread.
Let me see if I can get simple excel sheet developed for this.
Try this before starting to make a new one. If you think its ok, fine. If not, you can go ahead and make one.
Follow the link
http://www.4 shared.com/file/S083gI3C/NR7_Tracker.html
Snap shows the SESAGOA is on NR7. You would have seen it expanded, today.
You can check whether a particular scrip falls on NR7 or not one by one, not all at the same time. You can check all the 1300+ scrips one by one. I think no one will check all the scrips. You may need to type-in the scrips you watch daily. This may be from 1-20 or 25 scrips may be more.
You need to download bhavcopy from exchange site and paste it on the particular worksheet. There are more information which are not necessary to find NR7 day. But it is one of the quicker process to bring the data in.
For Monday, you need to download today's bhavcopy and paste it on Sheet8-16th June.
For Tuesday, you need to paste it one Sheet3-17th June.
Snap shows that which date falls on which sheet. So you can accordingly paste it in the particular worksheet. Don't get confused because of worksheet's are not in order.
In sheet6, (in cell A2) type-in the scrip you wanna check. If it's NR7, it will show "YES" with yellow background in column D.
File format is xlsx. Some of you may not able to open the file. I tried to save it in xls format. But warning popped up that some of the feature may not be available if I save it in xls.