Antenna help/ suggestions

[jwt873]

The reason i dont like chim. Mounts is that your antenna gets covered in soot etc.

Darn.. I meant to mention that in my post.. Depending on what fuel you heat your house with.. Not only can antennas get sooty, but they can corrode as well.

If you're in a warn climate where the furnace or fireplace isn't going all the time, this won't be that much of a concern.

 

[bkspear]

Darn.. I meant to mention that in my post.. Depending on what fuel you heat your house with.. Not only can antennas get sooty, but they can corrode as well.

If you're in a warn climate where the furnace or fireplace isn't going all the time, this won't be that much of a concern.

I am in Atlanta, GA so using the fireplace is not really a concern. I have lived in this house for over 10 years and I think Iv used the fireplace twice. Thanks for all the great info guys !!

 

[mmckenna]

I don't use my fireplace, so soot isn't an issue. Also, I'm on the coast in California, high winds for us are <50mph. Also, you've got to be smart enough to not try and overload anything. I've got a single discone on there and it's been up (with a few different antennas) for 12 years. I don't know what they make chimneys out of in other parts of the country, but ours are stout enough that a strong wind blowing on a 1 1/4 mast with a small antenna on it doesn't present enough wind loading to be an issue. After all, this is earthquake country. If the chimneys were so weak they couldn't support a small antenna, a small earthquake would have taken out my chimney many years ago. My home survived a 7.1 quake back in 89 without an issues. I'm not concerned about my antenna install.

The chimney strap mounts don't move around if they are installed correctly.

Finding what works for you depends on your budget, abilities and what you will tolerate. Chimney mounts are cheap and easy and will work fine for low wind load antennas. Of course the actual construction and condition of your chimney is going to dictate.

Other option would be the "Ventenna" if you want low profile and easy install.

 

[popnokick]

bkspear- Something else to think about in choosing the type of mount you use for your VHF/UHF dual band antenna: Do you plan to upgrade your license in the future and get an HF rig? If so, you'll need an HF antenna. The simplest and least cost HF antennas use wire... so would it be helpful if the mount on your roof (regardless of type) is at some point usable as the center, off-center, or end point of a wire antenna? The ability to use the mount / mast as an anchor point for a wire antenna is frequently employed by many hams, and may influence your selection of type of mount and location of the mount. Not trying to make it more complicated, but a good Scout (and ham) plans ahead....

 

[dsalomon]

I would very seriously reconsider the use of a chimney for an antenna. I have seen first hand and heard many other stories of an antenna taking down a chimney. Chimneys are engineered to withstand only their own weight and nothing more. A lot of people get lucky using chimney mounts with small, low weight TV antennas. However, as the chimney ages, the mortar gets weaker and unless you re-point it on a regular schedule that's a disaster waiting to happen. If you live somewhere that can have high winds, even for short periods of time an antenna adds a LOT of stress on a chimney.

Do some googling on using chimneys for antenna mounts.

 

[jackj]

Brick and mortar chimneys are not designed or constructed to withstand side loads. A chimney mounted antenna will stress the mortar joints beyond their limits and, over time, break the bond between the bricks and the mortar. If you have access to the chimney then you have access the peak of your roof so why not use a roof mounted tripod and eliminate all chance of chimney damage?

 

[dsalomon]

+1 to jackj's comment.

Not only is chimney damage a very real possibility, but also personal injury to someone on the ground, depending on the chimney location.

Also consider access to the antenna for maintenance. If mounted on a roof tripod, maintenance becomes easier than if strapped to a chimney.

 

[popnokick]

Roof tripod = holes in roof. Eave mount, no holes in roof. Yes, roof tripod will accommodate very large antennas. But that's not what the OP is trying to do.

 

[captncarp]

Antenna Soot

When I was a RM in the US Navy. One ship I was on the antennas were at the most twenty feet or less from the stack. The ship had oil fired steam boilers. We had to notify the fire room when we wanted to go aloft and clean the soot off the antennas so they wouldn't blow down the boilers. One time they forgot and blew down a boiler until the Chief caught it and put a stop to it. Too late for us. Glad I was in dungarees and not undress whites.
I think we use to do it every month at least. And always underway. All the antennas were affected by soot.

 

[mmckenna]

Must be a state building code here in California, our chimney is rebar reinforced from the foundation to the cap. Like I said, I guess other parts of the country do things differently. I guess living in earthquake country pays off in some ways. Just about everyone here has their TV antennas mounted to the chimney and I've never seen one fail.

You should certainly look at what your specific needs are. Planning for future antennas would be a good idea. Designing your mounts for future wind loading is a good idea. Talk to local installers and see what they recommend. Talk to your local amateur radio club for additional input.

 

[bkspear]

So I think Im going to go with the Diamond X-50A antenna but use an eave mount and not a chimney mount. Can this antenna use the eave mount or do I still need some type of mast for it? Thanks.

 

[NDRADIONUT]

It should be mounted on a pipe but it also could be screwed into wood instead of using the u bolts...

 

[bkspear]

It looks like this one does have a pipe

 

[mmckenna]

Those work pretty well if they are installed correctly. Trouble I've seen with them is when the eaves are rotted out or split, as you'll find one some older homes. Often the "hardware kit" that comes with these rely on heavy wood screws or short lag bolts for anchoring into the eaves. I'd recommend through bolting with big washers or another way of spreading the load out.

You can also make one out of uni-strut pretty easily.