If you can get power up there, that’s the best way. Just put the whole shebang up. I’m about to do the same with my home setup - all I need is power because my WiFi will have no problem hitting it. hmmmm now i’m th inking again.
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Adding power to the roof will require a separate conduit to the roof. Coax and AC power cannot be in the same conduit…that an Electrical Building Code issue.
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Is that a restriction on 120 vac?
Run dc and reg at box?
POE a possibility?
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The only restriction that I am aware is that 120V (and higher) circuits can only share conduit with other cables with at least 600V insulation rating. Since most coax and data cable is difficult to impossible to find with 600V rating, most simply state it as not allowed.
But there shouldn’t be any issues that I am aware of with 24V DC in the same conduit as coax or data, then using a clean buck converter to get various lower voltages as required. And the ubiquity should be fine on the 24V minus considerable voltage drop, several K5LRK members run theirs off single 12V SLA batteries.
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Figured we’d have to have the conduits run up the side of the building by an electrician anyway. 2 big ones for RF and low voltage, and one small one with 120VAC and a GFCI at the top. Or bottom where we can reset it…
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Even better if we can feed the 120VAC circuit from an inlet ( like used for wall mounting flat panel TVs ) down in the E-lab. That way we can run small UPS if needed and keep it in the climate controlled area.
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I like that idea of 2 large and 1 small conduits to the roof. Add a weather-proof entrance service cap to the top of the conduits and we are in business.
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For the big conduits at least, I was thinking in terms of a box at the top on the inside face of the wall. I’ve seen the 90 elbow/boxes used for that. The kind that has the removable back to help feed cables.
This would help keep bend radius down for coax, and give us the bottom of the box onto which connectors could be mounted for the roof side interface to the coax. If we make it a good sized box, we could also put out power supplies in it for whatever we mount on the roof. Or maybe we need a seperate box for that specific equipment, since that’s where low voltage and high voltage meet. Not sure how that part of the code works.
If we can get access at the new location to a suitable spot for a ground rod or 4, those hooked to a copper plate in the bottom box with polyphasors might be a great idea.
I have an electric jackhammer and the ground rod driving tool, so a non-concrete spot ( or 4 ) would be wasy to work.
A large box (2 or 3 cubic foot size ??) on the roof that is connected to the conduits would have to be rated NEMA 4 to provide a water tight enclosure. That would allow us to add or subtract cables as needed. Coax feed-thrus out the side panels can be easily added. An AC outlet inside and outside the box would provide power for other equipment as needed. Our current antenna on the building has the coax lightning suppressor grounds connected to the roof metal flashing material. I assume this flashing material is grounded to the steel frame of the building.
As for a good ground connection in the Electronics Lab… we should be able to fish a ground wire out next to the water pipes that exit the side of the building as part of the building’s fire suppression system located in the corner of the lab. No concrete there, just grass and plenty of room to pound in a grounding rod. Or may just connect to the 8 inch water main that enters the building…that should be a good ground.