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FM antenna question

I am picking up an old antenna tower from a family friend tomorrow morning. The tower is 28 feet tall, but with an additional 10 foot section for a yet to be purchased rotor and about three feet of the tower concreted into the ground, i'm looking to have a final height of up to 35 feet, double my existing height of 18 feet.

My questions..

1.) Can I expect a big difference in reception from 35 feet up as opposed to 18 feet?

2.) Will I have better luck with distant (over 40 miles) LPFM's and translators? Or will I get better results with full-power stations?

3.) With my 18 foot tower, I get a lot of electrical interference from the neighbors house. 35 feet is far above the rooftop of the neighbors house, so would that interference be eliminated?

I still need to refurbish this tower, buy a rotor and all of those accessories and then cast the tower in the ground. It will probably still be about a month before i'm really rolling with this new set-up. When it's complete, i'll post all of my distant catches.
 
a few thoughts initially:

1) Have a professional tower installer evaluate the structural integrity the tower to make sure it is safe to climb - better yet, have them install and climb it, and install your antennas. If there was some means of attaching the antennas to the tower and running the feedline to it (in other words, "prewiring" it) I would favor that. Of course, that may necessitate a means of installing the tower so it could be lowered back down, some kind of mounting arrangement...
I have never personally installed or owned a tower, the amateur radio/ham operator websites I am sure have plenty of information on towers. You may be able to locate ham radio people in your community to help you with your tower installation.

Make sure the tower is safe to climb if you intend to climb it, that you have the proper safety equipment to climb, or have a professional evaluate the tower to see if the tower is worthy of climbing. You must already know that your community's zoning permits the tower. Also observe all safety precautions to erect the tower itself and attaching any antennas, hardware, feedline, etc...

2) "Will I have better luck with distant (over 40 miles) LPFM's and translators? Or will I get better results with full-power stations?" Like the disclaimer says 'your results may vary'. There is no way to predict from afar what will happen, there are many variables: terrain, the power of each station, the efficiency of your antenna system, the sensitivity, selectivity and capture ratio of your FM receiver/tuner.

Line of sight calculator: there are several online, here is one of them: http://www.qsl.net/w4sat/horizon.htm
I am sure that you know you can get the AGL from radio-locator.com or the fcc.gov website http://www.fcc.gov/mb/audio/fmq.html
As for your location, I think maps.google.com has a feature to determine your receiving site AGL.

3) Depends how strong the interference is. It's best to minimize the interference at its source. Perhaps you could investigate with your neighbor what the source(s) of interference are. Depending on what the source(s) of interference are, there are some solutions available out there. Again, the ham radio people are usually quite familiar with issues such as these, and many would be happy to answer your questions and help you out.

This answer is not meant to be inclusive. Anyone else have some ideas for lawppy?

Best of success in your DXing endeavors!
 
stormy01 said:
Try this site instead to determine your terrain: http://terraserver-usa.com/
Sorry, I thought maps.google.com had the height in feet above sea level but that doesn't appear to be the case.

"Google Earth" which requires the download and installation of special Google software to make it function, DOES give you the elevation of the earth at any point you move your cursor. Access to Google Earth is free.

You can also read lat/long for any location of your cursor. By using the calculator pages from the FCC Web or other locations, you can locate two points on the earth (your receive and their transmit), get the co-ordinates of each location and then get the distance between the two locations calculated, and the azimuth for pointing your antenna.

Another interesting feature of Google Earth is to turn on the terrain, and then tilt everything over (I'm sure there is a more appropriate term for this) and look at the mountains and ridges in 3-D. (This may not be a biggie if you live in Kansas, for example.) Here in the vicinity of the Blue Ridge Mountains it is interesting and useful.
 
landtuna said:
Is the subject of this post correct? You're doing all this work to DX FM?

Why not? This tower is pretty much being given to me and the old owners have no use for it, so i'd be foolish not to take it.

You must already know that your community's zoning permits the tower.[\quote]

I talked to the Neighborhood Services dept. this afternoon and they have no problems with a 35 foot tower.

You may be able to locate ham radio people in your community to help you with your tower installation.

Locating the ham radio people won't be a problem. My brother is a pretty avid hammer and is looking to become a general this summer. He's sure to have a few ham buddies who could help with raising the tower.

I'm pretty well set with most of the technical stuff right now. Thanks so much for the input so far!
 
Lawppy said:
My questions..

1.) Can I expect a big difference in reception from 35 feet up as opposed to 18 feet?


I would say YES.

Being that FM is like TV, this reminds me of when I was growing up in south Jersey just outside Philly and we also had an antenna in the attic. One day out of curiosity, my father and I turned it in the direction of New York and we got all their stations though they were quite snowy. This was in the mid afternoon in winter. We then had to turn it back in the direction it had been in for the local channels. I was so fascinated by being able to get the NY channels that I begged my father to buy me another antenna to put up there for my room, which he did. Not long after that, I wondered why we couldn't have an antenna on the roof like some of the neighbors. (which were aimed at Philly anyway) Even before we mounted the antenna on the roof, my father explained that the reception would probably be better and he was right. It had to have been only 15 feet higher but there was sure an obvious difference in the reception of the New York stations. They were still snowy at the normal worst reception times in the afternoon but still not bad either. And when the conditions were right on those mornings and evenings in spring and summer, they were as clear as the local stations. There were even some times where they were so clear, they didn't even have those "lines" on the screen that are so common with co channel interference.
 
The height will help. I lived 62 miles from Milwaukee and I raised an FM antenna about 20 feet higher than it was just to hear one particular FM out of Milwaukee. The strength was better & there was less fading.
 
radioman148 said:
The height will help. I lived 62 miles from Milwaukee and I raised an FM antenna about 20 feet higher than it was just to hear one particular FM out of Milwaukee. The strength was better & there was less fading.

I once did something similar about 15 years ago to hear one particular station, except that I rigged up a UHF antenna. When you like what you like you make accommodation.
 
Silkie said:
radioman148 said:
The height will help. I lived 62 miles from Milwaukee and I raised an FM antenna about 20 feet higher than it was just to hear one particular FM out of Milwaukee. The strength was better & there was less fading.

I once did something similar about 15 years ago to hear one particular station, except that I rigged up a UHF antenna. When you like what you like you make accommodation.

Later on I put a rotor on it and got stations in all directions.
 
radioman148 said:
Silkie said:
radioman148 said:
The height will help. I lived 62 miles from Milwaukee and I raised an FM antenna about 20 feet higher than it was just to hear one particular FM out of Milwaukee. The strength was better & there was less fading.

I once did something similar about 15 years ago to hear one particular station, except that I rigged up a UHF antenna. When you like what you like you make accommodation.

Later on I put a rotor on it and got stations in all directions.

That was something I didn't think of. LOL
 
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