The phrase "same frequency" means that two or more things are in sync or on the same page. It suggests that there is a mutual understanding or agreement between individuals or groups. Full definition
They get sick, die, murder, lie, cheat, steal, go broke, get rich, sprain their ankles, all with the exact same frequency as non Christians. (nakedpastor.com)
(Scary thought: Your microwave operates at almost the exact same frequency as your Wi - Fi connection.) (discovermagazine.com)