CREATE TABLE table_13869651_3 (frequency VARCHAR2, part_number_s_ VARCHAR2)

How many different frequencies does the model with part number ado540biaa5do?
SELECT COUNT(frequency) FROM table_13869651_3 WHERE part_number_s_ = "ADO540BIAA5DO"
SELECT COUNT("frequency") FROM "table_13869651_3" WHERE "ADO540BIAA5DO" = "part_number_s_"