On phones and demarcations

Some time ago I mentioned the bonus chore that I had to do: My diagnosis of failed DSL pointed the finger at my home's phone wiring, strung under the eaves some time between 1955 and ~1960 (whenever phones were retrofitted to my basic house built in 1954). I've proven to my satisfaction that the house wiring was at fault: new Cat 5e wiring strung across the kitchen, through the hall way, and into the project room worked very well for both DSL and phone, even eliminating a slight hum on the phone.

So I'm left with the chore of rewiring the house phone, and I've delayed it in the face of more urgent chores to get the house weather tight. I've also been scratching my head about how the phone-company owned lines are connected.

Pictured below is a pair of boxes that was making me scratch my head. They are fed from the phone line (large black line entering from top). The box at left usually has a plastic cover, but I've pulled it off to show that there's really nothing much inside except the two terminals that used to supply the old house phone and which now supply my new Cat 5e cable (gray sheathing). Faintly visible on the outside of the right hand box is "Bell Systems". A couple holes from old mounting points have yet to be filled - part of my final stucco repairs this coming weekend.

I wonder what's under that cover? A real piece of telephone history, apparently. Had I only looked at Wikipedia I would have identified this earlier. Both of these are demarcation points: the last piece of the phone company owned phone line, also known as minimum points of entry (MPOE).

But why do I have two demarcs? I just need one, right? Here's what I think:

The phone line comes into the smaller and newer demarc on the left where there's probably a lightning arrester underneath the four hex head bolts. The lightning arrester requires a connection to ground, and this is provided by the old demarc. See the wire heading into the gap between stucco wall and concrete patio? That's the ground wire.

If I want to move the demarc it still requires a ground connection which is problem for this house since it was originally wired without grounds at all. Any new ground connection should be bonded to the new electrical panel's ground, which is nice and solid. However, I've yet to wire anything new in the kitchen, which is the room nearest the demarc, just on the other side of the wall. Therefore there is no nearby ground. That will soon change.

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