You simply need to adjust your 962 to receive on a distinctive ring.  To do this:

 

1.  From the front Op Panel of the 962, press the 'Mode' button until 'Fax' is selected

 

2.  Press the 'Menu' button 15 times

 

3.  Press the 'Select' button

 

4.  You will now be in the 'Advanced Fax' menu.

 

5.  Press 'Menu' 7 times

 

6.  You will now be in the 'Ring Pattern' submenu

 

7.  Using the left and right arrow buttons, find and select which ring type your phone company is using for your distinctive ring, it should probably be either 'double' or 'triple'.

 

8.  Once you find the correct selection, press the 'Select' button

 

That's it!  Your 962 will now only pick up on the distinctive ring that you selected...