Getting a new roof soon. Good time for adding a mast?

[JoshuaHufford]

I would like to put up a base antenna/s at my home. I have a great receive site at my Father In Law's shop, and I already have some radios there for ATCS railroad stuff and an audio feed as well, the site is about 140 feet higher in elevation than my home (that is quite a bit for central Missouri) and there are a lot less trees around. However I'd still like to have a base antenna here at home, there is only so much scanning you can do remotely.

My home is a hip roof so I don't have any gable ends to work with.

I do have an unused chimney at the back of the house but I know those aren't ideal places for antennas, but I did have a temporary setup on that chimney for a few weeks and reception was good, that would also be the shortest path for the coax to enter my home and it isn't too far from my electrical ground rod.

I also have an unused tilt over flag pole in my back yard, it is about 20 Ft. tall, however the coax run to get into my home would be about 60Ft. and I'm not sure if I can safely bond it to my home ground system, at least not without a lot of expense. I would also have to suspend the coax in the air that distance from the flag pole to where it enters into my home, burying it would require busting up a LOT of concrete.

Adding a tower is not in the budget right now. I didn't know if adding some type of roof mount while the roof is being replaced is a good idea? I've not considered this type of mount before as I was concerned about possible leaks.

Thoughts?

 

[mmckenna]

the site is about 140 feet higher in elevation than my home (that is quite a bit for central Missouri) and there are a lot less trees around.

So, do you get a nosebleed when you go there? Just kidding…. Coming from the west, getting out on the plains is quite a shock for us. I learned to navigate by knowing where the mountains were. When I get out in the plains, I get lost….

I do have an unused chimney at the back of the house but I know those aren't ideal places for antennas, but I did have a temporary setup on that chimney for a few weeks and reception was good, that would also be the shortest path for the coax to enter my home and it isn't too far from my electrical ground rod.

Yeah, depends. In California, at least in my area, chimneys are reinforced with rebar on all modern construction, so they work OK. Not sure about the rest of the world. I've had masts on chimneys since I was a kid. It's pretty standard out here (or at least was) for mounting your TV antenna, or back in the day, your monster CB antenna. But like I said, building codes are different around the country, so probably not your best choice.

We've done similar things at work when buildings are being designed. Usually we make sure we have some weather head feed through's onto the roof, I usually as for 4" conduit, but that not suitable for residential…. But, now is certainly the time to ask. Putting a roof jack up there with a weather head is a good idea. I'd probably go with at minimum a 2 inch pipe for cable feed through.
Make sure the feed through conduit is grounded if it's steel. If it's PVC, you're OK.
The roofers could install a mast with a roof jack around it. That might be a good option. Keep it reasonable, 10 feet or less. They can anchor it into the rafters in at least two places. We had something similar done when they built our PD office. We have 4 masts sticking up about 3-4 feet above the roof peak. The mast material is 2 or 3" rigid conduit with a weather head on top. Has worked out really well. All the masts are grounded to building ground.

Designing it now to keep your cable runs short is a good idea. Considering ground now will save trouble later. A ground rod near the antenna base with it bonded back to your homes ground rod is required by code.

I also have an unused tilt over flag pole in my back yard, it is about 20 Ft. tall, however the coax run to get into my home would be about 60Ft. and I'm not sure if I can safely bond it to my home ground system, at least not without a lot of expense. I would also have to suspend the coax in the air that distance from the flag pole to where it enters into my home, burying it would require busting up a LOT of concrete.

Yeah, doesn't sound like a good plan for 20 feet. Any cable you put under ground, even in conduit, is going to get wet, so that means you'll need a bury rated cable. That's usually a gel filled cable, and it's nasty stuff to work with. Suspending it in the air sounds like that wouldn't pass muster with your minister of war and finance.

Adding a tower is not in the budget right now. I didn't know if adding some type of roof mount while the roof is being replaced is a good idea? I've not considered this type of mount before as I was concerned about possible leaks.

Towers sway. You wouldn't want one on your roof if it was much taller than 10 feet or so. You really want those ground mounted, but it's common to attach them to the eaves end for some support.

Maybe figure out where you would site a tower if you get the funds. Have them install a cable feed through on that end of the house. Could be as simple as a vent grate that you remove later to route your cables.


Good thinking, this is the time to do that kind of stuff.

 

[JoshuaHufford]

As always thanks again for the good info you provide.

I'm honestly not quite sure what you mean by roof jack. Could you expand on that or give me a link to an example?

 

[mmckenna]

Roof jack. That thing-a-ma-jigger that goes around the vent pipes on your roof to seal them. The roofers can use these around conduit and masts to properly seal them.

Gibraltar Building Products 1-1/4 in. - 3 in. Plastic Adjustable Pipe Flashing with Hard Base and Rubber Collar CMIHB31 - The Home Depot

This adjustable pipe flashing can accommodate 1-1/4 in., 1-1/2 in., 2 in. or 3 in. Type "B" installations. The elastomer collar has been tested for ultraviolet, ozone and weather resistance and heat tested

www.homedepot.com

 

[JoshuaHufford]

AH! OK that makes sense.

 

[JoshuaHufford]

OK need some more input. I don't think there is anything in my attic that I can ground a mast to, and there is no easy path to the basement where my electrical panel is from the attic.

Would it be OK to run an external ground wire down the roof then down the side of my house to my ground rod?

Second, I want to coax to come into my basement, and I already have a path through the concrete wall to get the coax into the basement. Is running the coax down the roof then down the side of my house OK?

If I'm not going to run the coax down through the mast is there a better option than a weather head to cap off the top of the mast?

 

[mmckenna]

Would it be OK to run an external ground wire down the roof then down the side of my house to my ground rod?

Yes. Run it inside PVC conduit to protect it. You can also paint the conduit to blend in with the house.

Second, I want to coax to come into my basement, and I already have a path through the concrete wall to get the coax into the basement. Is running the coax down the roof then down the side of my house OK?

Yes. Like above, run some 2" PVC conduit so it's contained and can be painted over to blend in with the house. Using an LB or a large PVC junction box will make it easy to transition into your basement. Just remember to stuff some insulation into the feed through pipe to keep cold air and critters out.

If I'm not going to run the coax down through the mast is there a better option than a weather head to cap off the top of the mast?

Yes. Have them put a cap on the conduit. If they use rigid conduit, have the threaded section on top (if they cut the pipe shorter than 10 feet), then just thread a cap on to it. You can always remove it later if you want to put a weather head on for different coax routing.

 

[JoshuaHufford]

Awesome, thanks again.

 

[BaoFeng_Blogger]

I also have an unused tilt over flag pole in my back yard...

Is there any way to cut off the pole at ground level and install it closer to your house?

73 to ya...

BaoFeng Blogger

 

[JoshuaHufford]

Is there any way to cut off the pole at ground level and install it closer to your house?

73 to ya...

BaoFeng Blogger

It could be done but it is set in concrete now, and the back of my house where I would want to put it has two problems, it is already concrete all the way up to the house, and it is 2 stories tall at the back which this isn't tall enough to get above that. I possibly could make it taller but any of that would be a lot of work.