CREATE TABLE table_2394927_1 (max_downstream_throughput___mbit_s__ VARCHAR, power___dbm__ VARCHAR)
SELECT max_downstream_throughput___mbit_s__ FROM table_2394927_1 WHERE power___dbm__ = "+17.5"
mbit/s สูงสุดคือเท่าใดเมื่อ dbm คือ +17.5
What are the highest mbit/s when the dbm is +17.5?