Just to add to your question that wasnt a modem on the house its a amp or a multi switch I think. If it is a multi switch I cant see why it was used since it only has 3 lines coming out ant there isnt a cable feed into it seems like a waste of equipment. As for taps you would know better that me because you work plant. Would power pass through the other tap ports or would it be stoped by the capasitors in the tap? And would power feeding in through the tap ports cause any problems to the tap? Im not refering to a catv/telco tap just your standard tap.
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