Its likely that older Access Points are not broadcasting a regulatory domain information element in the beacon, or have not been configured for operation outside of the US. In either case, I imagine most US manufacturers of wireless adapters default to the US channel set.
Its likely that older Access Points are not broadcasting a regulatory domain information element in the beacon, or have not been configured for operation outside of the US. In either case, I imagine most US manufacturers of wireless adapters default to the US channel set.