I'd recommend adding two Tables. The first should contain the Call Log details (the call itself as well as a unique number that can be used to identify the call). The second table will just have two fields: A Call ID and a Member ID.
Then every time you get a call, you add a record to the Calls Table and then, for every Member that responded to that call, add a record to the other table with both their Member ID and that call's Call ID.
So you'd have a Table setup something like the following. . .
Members:
Code:
MemberID|MemberName
1|Rawb
2|pentabarf
3|TheShabz
4|pbaldy
Calls:
Code:
CallID|Address|Time
1|123 Street St.|09/09/2010 14:21.23
Responders:
Code:
CallID|MemberID
1|1
1|2
1|3
In the above example, Rawb, pentabarf, and TheShabs all responded to the call to 123 Street St. (while pbaldy's wife was called to watch both him and the phones).