Finding text characters in string

[Rasberry]

I want to check a field to see if it has a "B" or a "C" or a "D" in it. Basically, if the rating on the security is less than an A- (has a B, C or D in it), then it violates the investment parameters. What function can I use to check a text string?

 

[jim may]

Excel Workbook
	A	B
1	A	FALSE
2	B	TRUE
3	C	TRUE
4	D	TRUE
Sheet1

Excel 2007

Cell Formulas
Range	Formula
B1	=NOT(A1="A")
B2	=NOT(A2="A")
B3	=NOT(A3="A")
B4	=NOT(A4="A")