Has anyone had any success or heard of someone having success mounting a large 7698 on something other than a tripod or tower?

I'm thinking a large J-pole... any thoughts on that? Any real alternatives out there?

I have a hd7697p on a tower.

The 7698 is even bigger.

What you're thinking sounds risky. It will either work or it won't. The risk you run is roof/wall damage + damage/breakage of an expensive antenna + damage/breakage of an expensive pre-amp + risk to a loved-one or stranger that gets impaled by a long pointy falling object. And if none of the above ever happens, everytime the wind blows you'll worry about it.

How about a properly mounted 7697 or 8 on a tri-pod or chimney.

I absolutely love my tower...no regrets whatsoever.

You have some experience with towers, if I recall, and large antennas. Maybe you should think about the 7697 if you're going to try it. I have pics of my set-up on my profile.

I don't really know if it is really true or not, but the Winegard spec sheet for the 97 and 98 shows a higher gain figure for rf7 (WBBZ) than the 98. I'm really happy with my reception and I'm not sure a better antenna would get me any more channels.

Jakeman3, I wouldn't attempt to mount anything larger than a 4-bay--or at the absolute most an 8-bay antenna--on a j-mount.

There are other options, as mentioned by HWP, such as chimney or wall mounts or tripods that are capable of supporting larger antennas.

Actually Jase88, I never really took a close look at the Wall mounts, considering the design of my home one of the wall mounts might be the perfect solution for me. Anyone out there mounted something like an 7698 or an HBU55 with a wall mount type of setup?

Jakeman3, Years ago I moved a tower in a fringe area and I temporarily set up the antenna on the roof using a guy wire system (http://www.channelmasterstore.com/PhotoDetails.asp?ShowDESC=N&ProductCode=CM-1820) while concrete was setting up and tower being reassembled.
The cost of this is in the area of $100 but I have seen less expensive. The damage to the roof was minimal and repaired with roof tar, and it might be worth checking out available OTA before you invest in a tower.

By the way, we're going with twenty feet of tower + a 10ft mast + rotor (old Channel Master) + 3ft mast + HBU55 with 7777 in Keswick ON. House is a bungalo.

Second question: I presume that with these tubes sunk into the ground, that I can consider my antenna and tower grounded. All I'll need to do is ground the RG6, right? Am I supposed to ground the rotator wire as well?
No do not assume that. No guarantee of good contact from stakes to plate to tower. Use proper ground rod, cable and clamp. Play it safe.

Good point. I have a 4ft copper ground rod. I will use it.

Thanks, Wilspin.

So, I'm looking for an alternative to a tower or tripod mount. Take a look at the attached pictures and let me know if you have any thoughts about this planned wall mount idea? I'm also looking to install a 7697/98 on top, congtrary to what the picture suggests.

Thoughts are welcome



http://www.digitalhome.ca/forum/picture.php?albumid=873&pictureid=4555

http://www.digitalhome.ca/forum/picture.php?albumid=873&pictureid=4554

Hey Folks - newbie here in Oshawa...love the forum and am hoping for some experienced input...

I'm putting up my DB8 with a rotor and CM7777 this weekend. My home has vinyl siding and my idea was to put up two sections of 10' galvanized pipe / EMT joined together, from the ground up sitting on a concrete slab as the base. Then, use two brackets to clear the eave to attach the mast to the house...Estimated clearance for the mast above the eave will be about 6 or 7 feet.

Questions:

1. Is it OK to have the mast sit on the ground (concrete slab) while attached to the house in the studs?

2. Is 6 or 7 feet OK for height above eave - unsupported above this height, with approx. 15 feet of the mast attached to the house with the two brackets?

I'm just making sure that my choice of mast material / height will be strong enough to withstand strong winds...

Any suggestions would be great...

I wouldn't go any higher and the rotor should probably be as low as you can put it.That way they'll be a little less weight up there to swing around.

Does Anyone see any problem with putting a large HBU55 on a 3ft tripod? The Antenna has a 145" boom?

I read somewhere that a 3ft tripod should only be used for booms up to 80" Although on the Channel Master website they make no referance to that whatsoever...

Jakeman,

I would guess that the guideline you heard about limiting boom lengths to 80 inches on a three foot tripod probably assumes the use of an all channel (2-69) antenna. Those antennas have a lot more metal towards the outside of the radius due to the wide wavelengths of channels 2 - 6. Your HBU55 is much less wide and a far greater proportion of its weight is near the centre. I think you'd be all right with it. But let's wait for advice from an experienced expert.

Torque is the problem. The wind resistance of the antenna is increased by its larger size. The rotational torque around the axis of the vertical would not be the problem, you could just re-align if it rotates, like what it done with rotors after wind storms. The problem is the rotational torque around the horizontal axis (where it mounts on/to the roof), with winds like the 100km just seen in Manitoba a few days ago, it would probably be ripped out. Guy wires added to increase the width of the stance might be an idea.

Have decided to abandon the wall mounts I described in an earlier post in favor of eave/gable mounts for my DIY GH6n3 in order to get it mounted higher than what was possible using the wall mount.

Facts:
- eave/gable mounts are spaced 17” apart
- mast is 1-1/4” OD 18 gauge galvanized steel pipe (fence top-rail)
- 4 ft. of mast will be occupied by the antenna proper
- each bracket is attached with 4 (four) 2” galvanized lag screws

My thinking is to have 7 ft of total mast length above the top bracket – 4 ft. occupied by the antenna proper and 3 ft. clear mast above the top bracket.

Would that be OK?
If not, what would safe total mast length above top bracket be?

1. Is it OK to have the mast sit on the ground (concrete slab) while attached to the house in the studs?

2. Is 6 or 7 feet OK for height above eave - unsupported above this height, with approx. 15 feet of the mast attached to the house with the two brackets?


Concrete is corrosive to metals. You'll likely find significant corrosion to the mast within a few short years. If this is otherwise acceptable to you, than there are no other issues with placing a mast directly on a concrete slab. Just ensure that you ground the setup properly (as with any installation).

I don't see an issue with your proposed mast configuration in question (2), based on the installation of a DB8.

Im trying to locate the best position on my neighbors roof, who insists on a chimney mount.(he does not want to intervene in walls, or roof)

The line from the chimney position puts LOS on the transmitter, and just thru the lower corner of another nearby neighbors roof (towards right), however this line would be on the downslope side of his own roof...

If he goes with the chimney mount (straps), he needs some 15-20 ft of mast pipe on the chimney to properly clear the adjacent upper roof level, towards which the antenna needs to be aimed...im not sure if 20 ft is available or if this is even a good idea ?

A second idea, would be some sort of eave mount, or a 40" J-pole, at the upper roof peak, but the fascia is quite narrow, and this would put his own roof top in front of the antenna, so im not sure if it will interfere?

In any case he is aiming into neighbors roof off to the right, and large trees, also about 10 ft behind (left) are the power lines, not sure how this will affect reception...?


http://www.digitalhome.ca/forum/picture.php?albumid=913&pictureid=4907

The utility lines look like telephone and/or cable, but there could be electrical lines above. Either way, not a good idea mounting an antenna within 10' or so of these lines. Many people believe that electrical lines are only dangerous if contact is made with them. This is not true. Holding a metal pole within close proximity to power lines can cause a lethal arc. It happened last week in Guelph when a man was using a metal pole to place Christmas lights on a tree.

And such a short chimney shouldn't be used to support 20' of mast without guy lines (which can't be used in this location due to the utility lines).

As such, my recommendation is an eave mount, using the eave in the background.

Thank you for your comments.

The utility lines look like telephone and/or cable, but there could be electrical lines above.

yes, the upper ones are electric, but not the highest tension ones, they are also insulated - but yes, I understand your emphasis on staying AWAY from them

...even WORSE, he wanted to put the antenna directly on his house's power drop mast (not shown) :eek:

And such a short chimney shouldn't be used to support 20' of mast without guy lines (which can't be used in this location due to the utility lines).


The chimney is about 6 ft high. I was thinking of using 2 chimney strap kits with the mast supported on the roof. - but yes, I understand your point re. the need to support a mast which is more than 10 ft unsupported past the topmost bracket.

Do you think a 40" J-pole would work on the eave (at the lower side of the upper roof - left corner (not shown)) - this is where the resulting aim angle will best clear a neighbor's house - the overhang is very thin however, maybe 3" wide

An eave mount, on the other hand, which places the antenna at the very peak, but puts the aim angle straight into the center of neighbor's roof...

In either case the roof surface lies in front of the antenna, and his power drop to the house is close to the antenna.


Thank you for any comments.

If I go with a J-pole & mount on the fascia, it seems like the fascia needs to be at least 6" wide, and the overhang less than about 8", whereas I only have maximum 3-4" fascia and maybe 10-11" overhang to clear...and I think making it wider will be a lot of work...?

"Insulated" power lines are often compromised by age, weather, and animals. Most power utilities don't replace them until they fail; which means some lines can be 40 years (or far more) in age. Don't place any faith in the insulation on a power line. ;-)

I don't like the use of j-mounts for OTA antennas. While they are used successfully in many cases, I believe they aren't strong enough for larger antenna and often lack aiming flexibility. I know Save & Replay in Mississauga sells them for antenna use. But as you don't have much of a fascia board to work with, I'd be hesitant. Unless you can somehow shore up the fascia board to support the full mating area of the j-mount.

But you're looking at a 40" pole on a j-mount? Might be tricky. What type of antenna do you plan to use?

Have you done a search for a used bracketed tower?! You may be able to pick a used one up cheap. The good thing with bracketed towers is that you can install them in the winter--just drive stakes into the ground through the base plate to support the base. And the bracket doesn't require as much fascia board width as the j-mount.