Winegard Company Mobile and HDTV Antennas

What is needed to get long range stations?

All things related to HDTV Home Antenna reception including antenna recommendations, channel listings, basic questions and more!

What is needed to get long range stations?

Postby Terfintv » Mon Jul 13, 2009 8:18 am

I live in Mt.Vernon,IL 62864 . I'm trying to get St.Louis,Mo stations. I have a forty foot tower with a rotor. The area around my location is reletively flat and i'm on a slight hill top. The nearest tree line is about a half mile away and my tower goes above it. This is a list of stations I'm trying to get. This info came from TVfool. (CH real) (Virt) (Signal NM dB) (Pwr dBm) (Path) (Dist. Miles) (Azimuth True) (Margin)
KMOV 24 4.1 -1.4 -92.2 2edge 77.3 282 284
KPLR 26 11.1 -2.4 -93.2 2edge 79.6 284 286
KSDK 35 5.1 -4.3 -95.2 2edge 79.6 284 286
KDNL 31 30.1 -4.4 -95.2 2edge 79.7 285 286
KTVI 43 2.1 -5.9 -96.7 2edge 81.3 282 284
These are all of the UHF stations I'm trying to get. I have one VHF station that I want to get. Here is the station. KFVS Real channel 12 Signal NMdb 6.8 Pwr dBm -84 Path 1Edge Dist Miles 67.9 Azimuth True 208 Magn 210.
I"m willing to install what ever is needed to get these stations. Even if I need to stack two attennas together? Thank you in advance for your recommindations.
Terfintv
 
Posts: 2
Joined: Mon Jul 13, 2009 7:35 am

Re: What is needed to get long range stations?

Postby KNP 2516 » Mon Jul 13, 2009 9:23 am

Sometimes performance cannot be listed as simple as how much do I need to spend.

There are limitations to UHF, no matter what the range.

You have to understand that UHF is line of sight.

Sight vs. sound

UHF is like a pin point of light. If you shine it in the air, it does not go down holes - valleys. If you shine it at the side of a hill, it does not go up one side and down the next. If you are standing on one side of a building it does not shine around the corner and to the other side.

VHF is like sound, if you yell, the sound goes up one hill and down the next. It goes through buildings and around corners.

What you had before was VHF and what you have now is UHF.

If you went to Chicago and stood on the shore of Lake Michigan, and looked out over the water - if someone built a 3,000 foot tall tower 40 miles from Chicago - you might still be able to see the red light at the top of the tower. That is line of sight.

Yes the horizon is only about 26 miles, but due to refraction of the light waves, the light bends over the horizon and lets you see the light at the top of the tower.

Radio waves are affected the same as light waves. Refraction, reflection and diffraction are the three main points to ponder.

So basically the first 40 miles, you have a line of sight transmission, great.
The next 15 miles you have the first reflection of the waves - hence 1 edge of the signal.
About 10 miles after that you have the second reflection of the signal - hence 2 edge of the signal.
About 10 miles after that - you have a third reflection - hence Tropo.

The first signal is the true signal, it is watchable and is very easy to receive with a good antenna, proper height and maybe even a small pre amplifier to overcome loss in the wire and splitters in the house.

The second signal is a reflection of the first signal, it is harder to receive, more prone to drop outs, pixelation, and static interference from local sources, motors, electric fences, automobile ignitions etc.
It can be improved by the use of a very good antenna and a pre amplifier. At that point, you have to remember that the best signal possible is going to be at the antenna and everything after that is going to be loss. Line loss, splitter loss, etc. At that point, the use of RG 6 Quad Shield is a must, along with a good amplifier - but at that point - you also have to remember that one local station can over power the amplifier and you could end up with a blue screen, even though you have a good signal on the roof for one station and so so signals for the rest. The second signal a antenna rotor is a must.

The third signal - the reception is going to depend on the weather and the time of day. The best pre amplifier is a must, along with the very best long range antenna. Even then reliable reception is iffy at best.

By the time you get to 65+ miles, about the only signal you are going to get is tropo. Sometimes on some days - if at all. You will get a signal. Any station that is less than 1000 KW in the upper ranges of UHF, or is close to another station in a near frequency - you are going to have problems receiving it. When the sun comes out early in the morning and the ground begins to heat up - you will get a signal from the inversion layer in the atmosphere. In the late evening when the ground begins to cool, and the sky is cold, you will get a second inversion layer reception for a couple of hours.

It is not a reliable signal to receive.

You also have to remember that Fog, rain, snow, flocks of migrating birds,trees, and leaves on trees, swarms of bugs, airplanes, buildings more than 4 stories high and anything else that can get between you and the signal is going to block the signal.

To get that signal, you have to look at what is in your first and second fresnel zones. If everything is good, which usually it is not, then you can make plans for a antenna.

My advice is to get the antenna as high as possible. 100 feet or more ( Height = Gain) and use a Winegard 8200U antenna and a Winegard 8275 pre amplifier. A good digital antenna rotor like the RCA model sold in the Lowes stores. Belden 1829 AC wire. Keep your antenna wire runs as short as possible - do not keep a couple of extra feet of wire looped in your basement - in case you need it. Keep splitters to a minimum - and no more than a two way splitter anywhere in the system. Splitters are not unilateral.

What that means is that if a splitter was unilateral - if I was to walk into a splitter, two identical me's would walk out the other side. We would both have eyes and ears and noses and arms and legs and torso's that were the same size.

Unfortunately all splitters has loss. A 2 way splitter has at least 3.7 db of loss, some have even more.

3 db of loss equals the loss of half the original signal.

When you go to a 3 way splitter you might have as much as 7 db of loss on any one port /More than twice the loss of the original signal.

Use crimp on connectors only and put the pre amp power injector as close to the television as possible.
Put the pre amp box as close to the antenna as possible.

Keep antenna away from all power lines and trees.

There is no one single antenna that does everything and there is no one real answer to your question.

The 8200U in my opinion is one of the best antenna's on the market for the reception of both UHF and VHF television signals for long range reception.
KNP 2516
 
Posts: 65
Joined: Sun Jun 07, 2009 9:35 am

Re: What is needed to get long range stations?

Postby winegard » Mon Jul 13, 2009 1:21 pm

Good afternoon Terfintv -

I ran your situation by technical services and an engineer. Here are the responses.


It looks like these stations are 70-80 miles away. So a tall tower and a HD7698P along with an AP8700 preamplifier will be needed. But I am afraid they will not be reliable. What are your thoughts?



I agree with what you have concluded. The signals will be weather-dependent but under most conditions, most of the DTV channels from St Louis could be received if great care was taken with the installation of the antenna products. Cables from the antenna to the preamplifier and from the preamplifier to the DTV tuner should be, at a minimum, new RG-6/U type coaxial cable. Cable connectors should be of the compression type, like those available from Ideal at Lowe's. If tower height could be increased about 20 ft., I estimate that there would be about 30% improvement to reception reliability over that at 40 ft.


You may consider the AP-8780 as the VHF DTV (KFVS) is inside the 36 dBuV contour for Mt. Vernon and the added UHF gain should equalize at the DTV receiver given the possibility of an longer cable run from the antenna.
winegard
Site Admin
 
Posts: 626
Joined: Fri Jan 30, 2009 3:10 pm

Re: What is needed to get long range stations?

Postby Terfintv » Thu Jul 16, 2009 1:10 am

Thanks for the information. I will look at riasing the tower hieght. The HD-7698P antenna Is there a extension that is availible for the UHF side of this antennas? I have heard of extending the boom to increase the range.
Terfintv
 
Posts: 2
Joined: Mon Jul 13, 2009 7:35 am

Re: What is needed to get long range stations?

Postby winegard » Thu Jul 16, 2009 8:23 am

The HD769P is about as large of an antenna you can build and receive maximum performance by adding more UHF directors to this large of an antenna will not help. The amount of directors you would have to add would make the antenna too large and cumbersome in relation to the add performance.
winegard
Site Admin
 
Posts: 626
Joined: Fri Jan 30, 2009 3:10 pm


Return to HDTV Home Antenna Discussion

Who is online

Users browsing this forum: No registered users and 0 guests

cron


Pressroom | Careers | Privacy Policy | Shipping and Returns | Supplier Portal | Dealers.Winegard.Com | Satellite Receivers and Programming

© 2012 Winegard Co. All Rights Reserved