Agreed re the master socket.
What is very noticeable is the huge improvement in the attenuation, noise margin and max attainable downstream sync. But whether there will be an improvement in the stability I have my doubts.
It's odd that the pristine junction box with the crimps is the first after entry to the building. Unless that is to deal with a cut cable from outside perhaps when double glazed windows were installed. I wonder if the outside part of that cable can be seen to go to a drop wire from a pole? Or if it runs outside then re-enters to the missing extension.
The decrepit one it leads to looks more likely, with what looks like underground feed and output cables. It's a very strange place to have such an old junction box if it isn't to do with the outside connection. I suspect there may be damp there, which could be the problem whatever the reason for the box existing.
Alternatively, I wonder if it is still functional. If it is even in the circuit.
Looking back at the pristine junction box, orange > orange and blue > white. With orange and white heading out together to the right. What?
Also, where do the valid pairings at the master come from. The don't seem to be present in any other pics so far, though maybe, looking again, we have the black/white + white/black pair at the decrepit box. Maybe going to the master.
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