If have simplified a problem I stated earlier:

If B1=1, delete the contents of A1. If B1 changes to any other value,
I do not want the former contents of A1 to return. Instead, I want to
be able to manually enter new contents, knowing that as often as B1
returns to equal 1, anything in A1 will be deleted. As I admit to my
novice status, the simpler the solution, the better. Thanks.

Michael