Gordon is obviously a long-time ham guru but I personally don't think scanning is as high up in his radio knowledge agenda so I guess that's why the oversight.
I have personally met Gordon (as MANY others have too) and I have even had dinner with him. A very nice guy and smart, but my take was anything above HF and the basics of VHF/UHF, he is not very well interested.
I really don't think the RJ45 is anything more than the direct wired (some sort of proprietary serial data connection, most likely) connection for the remote head; it would be nice if it were Ethernet but I really highly doubt it. Still, nothing is technically stopping one from using CAT5/6 cable for extending the reach up to the point that the serial data begins to degrade at least though most of that is round and less convenient for a side-connected mount.
I'm going to bet that this is NOT ethernet in any way. The time to implement a TCP/IP stack just for coms between the head and the main unit is not very well suited for this application. Unless there was an actual need for the long distance remoting and others have speculated on, I don't see them doing it. Also, I am going to go out on a limb and say it's most likely pin 1 to pin 1, straight through. When we developed the RH96 remote head interface kit for the Unidens, we used CAT5 cable because we knew it was cheap, readily available, you could make one yourself to a custom length and it had enough conductors to do what we needed it to do. Along with that came the headache of explaining to every one out of every four email inquiries why it was NOT ethernet compatible
