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Discussion Starter · #1 · (Edited)
Colorado Springs, West: Reception Guidance Needed.

Hi all!

I've been using an antenna for over 8 years. I moved to a new house 3 years ago and even though I'm much closer to the stations, my reception on certain channels is very poor.

I essentially cannot receive Channel 21.1 and sometimes 5.1, but 5.1 is much better. I'm 5 miles from the stations, but I live on a mountain and they're on top of a mountain 5 miles away. I have one TV, that's newer, that does get 21.1 fairly well, but not always. My HDHomeRun has serious issues with it.

My question is, should I be using a different antenna? I can't use one inside an attic because I have vaulted ceilings. I want to minimize the amount of times I go onto the roof since I'm afraid of heights and roof is very steep. I get poor radio reception as well and would really like to improve that. I do have a Diplexer to combine UHV and VHF antennas.

Location: Colorado Springs, West. - Gold Camp Road
Antenna: ClearStream 2 Complete Long Range UHF/VHF Antenna
Height: 45' above ground mounted on top of a a chimney.
Cable: RG6 Quad - From Southwire.
Cable Run: 150 to 200' to splitter
Split to 3 tv's and 1 HDHomeRun.
The runs from the splitter range 25' to 100'.


The antenna is mounted on my chimney and the cable runs outside down to our basement, 3 levels, into our home.



TVFool Report: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=f1f0d912e147e2


Here's what I get from antenna web.



I've tried an amplifier from RadioShack. It seems to make the other channels signals stronger, but does very little for 21.1. This isn't the exact model I have, but very similar.
 

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Discussion Starter · #3 ·
Calaveras-

Thank you.. I read the thread and updated my original post. I think I provided most of the information necessary.

Here's the TVFool Report: TVFool Report: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=f1f0d912e147e2

That's much more elaborate than the antenna web report.

I'm open to buying whatever antenna is necessary or even making one. I do have some soldering experience.

I thought about using RG11 for the outside run, since it's so long, but thought it was overkill.
 

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Your TVFool Report indicates that ABC, CBS and PBS (Ch8 in Hi-VHF Band) should be easy to receive....but NBC and FOX are going to be very iffy, so I would recommend the Highest Gain UHF Antenna you can afford, such as DB-8e, or for even higher Gain, a Single DIY FF4 (Optimized Free Form 4-Bay) and if that isn't enough try stacking TWO of them for a DIY FF8 = 2 x FF4, either Horizontally or Vertically (wider Beamwidth):
http://imageevent.com/holl_ands/multibay/4bayrefl/uhffreeform4baydblanglreflopt
http://imageevent.com/holl_ands/stacked/horizontallystackeduhfantennas/horizstackff4dblanglereflhhh
http://imageevent.com/holl_ands/stacked/verticallystackeduhf/vertstackff4doubleanglerefl
http://imageevent.com/holl_ands/multibay/compare [Various Comparison Charts]

If you click on the TVFool line for FOX, the fol. Profile is found:
http://www.fmfool.com/modeling/tmp/ec1780e867/Radar-FM.png
The signal from the Tower (abt 9500-ft AMSL, with 1-deg Electrical and 2-deg Mechanical Down Beam Tilt) is Diffracted off of THE HORNS (abt 9100 ft, abt 0.9-mi away)....and from there it is LOS to your location (abt 6800 ft). Note that THE HORNS is a look down angle of about 4.7-deg, which is probably NOT below the Broadcast Elevation Angle Pattern, which means what gets Diffracted down to you should be in the ballpark of what TVFool predicts.

Using TVFool's OnLine TV Map function and your zipcode I was able to relocate the location Icon onto Gold Camp Rd until it was within 0.1-mi of the distance and within 1 dB of the NM calculated by TVFool for FOX. When looking at predicted FOX signal strength in your neighborhood, it looks REALLY BAD (Purple) on the West side of the road..and VERY POOR (Blue) on East side.

I entered the LAT/LONG from the TV Map display into FMFool and found the fol. results:
http://www.fmfool.com/modeling/tmp/ec1780e867/Radar-FM.png
Although there are FOUR FM signals were Extremely Strong (-14 to -15 dBm), 90.5 MHz (-18.4 dBm is still Very Strong) is the only 2nd Harmonic threat to Ch8 reception.

Although you ALSO have four Very Strong TV Signals, I would recommend you try using a Preamp known to have a Very High Overload resistance, such as the pricey Antennas-Direct Juice or lower cost, almost as good Winegard LNA-200....and you MIGHT need a small amount of Attenuation (try 3 & 6 & 3+6 dB devices) on the Preamp Input to try and Maximize the Spurious Free Dynamic Range:
http://www.avsforum.com/forum/25-hd...quantifying-preamp-overload.html#post32471466

PS: SFDR is Spurious Free Dynamic Range [Difference between Strongest Signal Level and the TOTAL Noise Floor], which is Maximized when the choice of Preamp and Max Input Signal Level results in the 3rd Order Intermod Noise Level being NO HIGHER than the Thermal Noise Floor. This allows reception of the WEAKEST signals when the Preamp is also passing strong signals (Dynamic Range):
http://www.arl.army.mil/arlreports/2007/ARL-TR-4235.pdf [See Figure 3 on pg3.]

Note that inserting a small amount of Attenuation on Preamp Input can "tweak" the strongest signal input level so that it is right at the "knee" in the Total Noise Floor curve. For every 1 dB of Input Attenuation, the 3rd Order IMD level is reduced by 3 dB...hence 4 dB Loss from adding a typical RF Splitter on the Preamp Input, results in 12 dB reduction in IMD.
 

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Discussion Starter · #5 ·
@holl_ands

Thanks you for the response. That's seriously a lot of information to swallow.

I'm interested in building the FF4, but can't seem to find a detailed build guide. Do you have a link? I may look into the DB-8e and will probably get the Juice amplifier.

and you MIGHT need a small amount of Attenuation (try 3 & 6 & 3+6 dB devices) on the Preamp Input to try and Maximize the Spurious Free Dynamic Range
Is this what you're referring to? http://www.amazon.com/Holland-FAM8-...qid=1429136167&sr=8-3&keywords=3dB+attenuator

Is that your Amazon store? :)

Will this be capable of picking up FM stations as well?
 

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I looked up the elevation patterns for your network stations in the FCC list of applications. At 4.7 degrees below the horizontal the stations range from about 10 to 14 dB weaker than what TV Fool predicts. KKTV drops to about 35KW ERP and KOAA is the weakest dropping to about 1KW ERP.

KOAA and KXRM have side mounted antennas lower on the tower which is why they are not LOS while the others are. This definitely makes things more difficult. I'd give the high gain UHF antenna a try with the Juice preamp and see what happens. It's unlikely you'll do much better.
 

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Discussion Starter · #7 ·
I looked up the elevation patterns for your network stations in the FCC list of applications. At 4.7 degrees below the horizontal the stations range from about 10 to 14 dB weaker than what TV Fool predicts. KKTV drops to about 35KW ERP and KOAA is the weakest dropping to about 1KW ERP.

KOAA and KXRM have side mounted antennas lower on the tower which is why they are not LOS while the others are. This definitely makes things more difficult. I'd give the high gain UHF antenna a try with the Juice preamp and see what happens. It's unlikely you'll do much better.
Thank you Calaveras. I think I'll give the DB-8e a try. I wouldn't mind trying the DIY option, but I'd need a guide.
 

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A 4-Bay is a 4-Bay is a 4-Bay....Multi-Bay Bowtie Antenna construction is pretty much all the same, except they differ in the various Dimensions used for the Whisker Lengths, Bowtie-to-Bowtie Separation, etc and which sort of REFLECTOR (Flat, Single-Angle, Double-Angle, Individual Reflector Rods) is presumed. Dimensions are listed in the 4nec2 text File that I ALWAYS upload.

You can also use nikiml's ON-LINE 4nec2 File Viewer: http://clients.teksavvy.com/~nickm/nec_viewer.html
And/or download the (FREE) 4nec2 software to View the 4nec2 File using the Geometry Viewer:
http://www.qsl.net/4nec2 ["Latest 4nec2 version" is ONLY file you need to D/L & Run to begin with.]

mclapp's website has details on his (lower Gain) M4 versions, including the (preferred) Double Angle Reflector, which is formed by taking a flat piece of Animal Fencing (preferably 1"Hx2"W...or 1x1 or 1x4) and then doing TWO Vertical line folds, each 8-in away from the Centerline. Note that my TALLER FF4 version (b) uses a TALLER 48"Hx36"W Screen Reflector (before bending):
http://m4antenna.eastmasonvilleweather.com/Drawings/PDF%20Drawings.html

For Indoor use, I would recommend using AWG12 or stiffer AWG10 for ALL wires (THREE of which are found in NM-B 12-2 or 10-2 "House" Wire. Copper or Aluminized Foil Tape (1/4 to 3/4-in width) laid out on a plastic sheet...or even cardboard is even easier and less expensive. For Outdoor use, an even stiffer wire is recommended for the Whiskers (ONLY)....mclapp usually uses AWG6 but it isn't critical...Copper and Aluminum Wire work equally well and 1/4-in Copper Tubing (for Refrigerator Ice Maker) can also be used.

Additional details for a 4-Bay with particularly GOOD construction techniques can be found here, which avoids locating wires close to moisture sucking WOOD and minimizes contact with PVC...note that dimensions only need to be within about a quarter inch and "DON'T SWEAT THE SMALL STUFF":
https://sites.google.com/site/maycreates/ota-setup/mclapp-4
And an entire thread re 4-Bay and 8-Bay Construction can be found here:
http://www.digitalhome.ca/forum/showthread.php?t=100137

FF4 design is fairly new, so I know of only (3?) people (nhcordcut, schoolbus & balm) who have reportedly built one so far....perhaps you can contact them to share experiences. User nhcordcut posted a picture of his DIY FF4 in his attic...which was working quite well, despite two feet of SNOW on the roof:
http://www.avsforum.com/forum/25-hd...na-will-work-me-southern-nh.html#post30650377
 
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