Hello, I have a dwl-800AP Hardware ver A2 and a dwl-800AP+ Hardware ver B2. The 800AP is easy to set up as a repeater with the "site survey" function. The 800AP+ requires you to know the mac address of the system to be repeated. No "site survey". I installed the latest firmware. It's still the same.
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It's probably an additional security provision. The MAC ID is printed on most equipment.