Between the Mountains

[LoTech]

Hi everyone,

I'm in the Kentucky foothills and I would like to get some input on whether it is worth the effort to try and get OTA television.

Here is my TV Fool Report.

I can get WYMT-DT fairly good with a 30 mile generic antenna mounted in my attic, but no luck on any of the other stations. I'm not really that interested in WAGV, but I would like to get WCYB, WKHA, and WVVK. Would it be possible to get reliable reception with the low signal strengths shown? If so what would I need?

Thanks,

LoTech

[mtownsend]

Is that report for the exact location of your house/antenna? Since the terrain is very hilly, it's important to try and get an accurate location for your analysis. Small positioning errors one way or the other might put the analysis higher or lower on the mountain and result in higher or lower signal strengths.

If the location is accurate, it looks like you're really socked in by mountains. With signals having Noise Margins down in the -16 dB and -21 dB range, I think it would be unlikely that you will be able to get reliable reception from this location. WYMT appears to be the only channel that can be received with any kind of reliability.

[LoTech]

Is that report for the exact location of your house/antenna?

Yep, mountains/hills on all four sides. WYMT comes across the small hill in front of my house. The rest come over more mountainous terrain. I drug the little red arrow all around the map for my house and yard before settling on the place with the best reception and generating the report.

On top of the hill behind my house the report says I can get about 20 channels, but that would be about a 2500 ft cable run. I guess that option is out as well.

[John Candle]

The long cable run can be done. The business that do cable line constructing for cable tv can do it , put a antenna on the hill , run hard line down , but you will not like the price. . Here is a way receive free satellite tv and does not cost much for the receiver and small dish. http://forum.tvfool.com/showthread.php?t=265 . And if you have broadband internet you can go with ROKU / NETFLIX.

[LoTech]

I have Dish Network with local channels, but their locals aren't really local. The main purpose of my setup was to get local news and information. I guess I'll just have to go with WYMT and forget the others. I may be able to get WKHA by running a cable a couple hundred feet or so up the hill and using a good pre-amp, but I think that the others are out of the question.

Anyway, thanks for all the help.

-LoTech

[John Candle]

Go to Slingbox , http://www.slingbox.com . If you know some one that lives at a location that can receive the local channels then the Slingbox HD can send the channels to your location.

[LoTech]

I checked on the hill behind my house for signal from WKHA. I ran a long extension cord from my barn up the hill and took a 4 bay bowtie antenna, a Coolsat 8000 HD receiver, and a small TV to what looked like a good spot. I could get WYMT OK, but no luck on WKHA or WAGV. On both I got signal from 85 to 97, but no lock on the channels which is strange, because I can lock WYMT at my house with a signal quality of 75. Does anyone know why I would get so much signal quality, but no channel lock?

[John Candle]

The small hill to the north? The tv stations signals are coming from different directions , reflecting Tv signals can do strange things .Go to the [Start Maps] part of tvfool , move the red balloon pointer to the top of the 2000 foot hill to the east , change the antenna height to 50 feet. Also select current plus pending , now click on circles next to the Tv station call letters now the colored tv signal strengths will show. Leave the pointer at the top of the hill. and look at the areas all around your tv receive location , the coloring.

[mtownsend]

Here's a map showing the differences between the two stations (this animated gif will flip back and forth between WKHA and WAGV). The hilly terrain breaks up the coverage quite a bit. For WKHA, the west-facing slopes are lit up. For WAGV, the signal is weaker because the transmitter is farther away, and it's mostly lighting up the south-west facing slopes.

To be in a good spot to pick up these two channels, you need to be at the top of a hill with a clear view toward the west and south-west.

[LoTech]

Hey guys, how accurate are the reports from TV Fool? According to the report I shouldn't be able to get any signal for WKHA where my antenna is (let alone in an attic), but the signal meter is running in the high 80s-mid 90s.

[mtownsend]

Most people report that their TV Fool signal analysis is pretty accurate as long as they get the precise location right.

The main exceptions to this are going to be situations where there is an error in the database (e.g., incorrect FCC record, a mistake in the application filed with the FCC, etc.) or if there is some kind of local obstruction that is affecting you that is not taken into account in the TV Fool model (e.g., hills that are too small to show up in the TV Fool terrain database, trees, buildings, etc.).



What strikes me as odd is that you're seeing some channels with a high reading on your signal meter, yet you get no picture at all. You mentioned seeing signal readings in the 85 to 97 range, yet on most receivers, a reading this high means that the channel can be easily decoded. There's usually no official word on exactly how these numbers are calculated, but on almost all of the receivers I've ever used, this means you should be seeing something.

Do you get a plain black screen or a message that tells you there's no signal lock?

Are there any units (like dBm or dBu) displayed next to the signal strength indicator? Maybe there's a way to figure out if the numbers represent anything real like signal power (and not signal quality, like most meters read).

Is there any way to confirm via the receiver's user interface that you're "locked on" to a channel or not? I wonder if the tuner has indeed locked on the the channel but is unable to display anything because perhaps the broadcast contains some data that the decoder does not understand.

There may be some minor problems with the way the Coolsat 8000 HD deals with OTA signals (http://www.satelliteguys.us/fta-mpeg...tml#post807547).

It's also possible that there is another signal source nearby that shows up strong on your signal meter, yet is interfering with the original broadcast. I have seen at least 1 situation where the local cable company's system was "leaking" enough signal to be picked up by a receiver even when it was not directly connected to the cable.



I'm not familiar with the Coolsat 8000 HD, so I'm afraid I can't offer much more. If you have any other converter boxes or tuners to test with, that might be the only way to check if the problem is specific to the Coolsat or if there's something wrong with the RF signals.

[LoTech]

Like most FTA receivers the CS 8000 has both Signal Strength and Signal Quality meters. I can verify that for FTA satellite the low threshold is around 35 Quality. I have been told that the threshold for ATSC is somewhere around 65, but I have been unable to verify this.

I am attaching a couple screen captures of Channel 12 (WYMT) at 207000 kHz and Channel 16 (WKHA) at 485000 kHz. In each picture, the green bar is signal strength and the blue is signal quality. WYMT holds pretty much steady at around 80 on both meters, but it locked at around 72 before I fine tuned my antenna. WKHA fluctuates rapidly between around 75 to 98 on both meters. This is what leads me to believe that I'm getting multipath interference. There are no metal ducts or foil backed insulation, and very few wires running in this part of the house so that shouldn't be too much of a factor, but it would certainly be better if it were outside.

Unfortunately my RCA HDTV doesn't have a meter. It simply does a channel scan and logs the channels, so I can't use it to verify the signal I'm getting on the Coolsat.

Hopefully this weekend I'll get a chance to move the antenna and see if I can get improved results elsewhere.

[LoTech]

Partial success. My wife was out of town today, so I had time to play with making an antenna. I decided on a placing two sets of dipoles cut to channel 16 from copper tubing into a collinear array with a wire mesh reflector.

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It was rough with 14-2 copper wire for the phasing lines, but it allowed me to lock WAGV in my attic with a solid signal quality/strength of about 87-90. (I chose the attic, because it's easy to get to.) No more wild fluctuation of the signal. This was a good sign as the array was cut for channel 16 instead of channel 51. When I tried it on WKHA (16) I got signal that would jump from 70 to about 85, fluctuate a little, and then drop back. Sometimes it would go up to 90, but no signal lock. With the fluctuation in signal quality, I guess I'm still getting interference.

When I get time I'm planning to modify this antenna or make a new one. What would be better in terms of eliminating multipath interference; to put a corner reflector on my two dipole antenna, or build a 2-high x 2-wide array with a flat reflector? If the 2x2 how would I run the phasing lines?

[mtownsend]

Originally Posted by LoTech

What would be better in terms of eliminating multipath interference; to put a corner reflector on my two dipole antenna, or build a 2-high x 2-wide array with a flat reflector? If the 2x2 how would I run the phasing lines?

My guess is that you'll get more out of the 2 x 2 array with reflector screen.

As for connecting them together with minimal loss, check this page: http://www.hdtvprimer.com/ANTENNAS/ganging.html

[John Candle]

At the >StartMAPS< part of tvfool with the antenna height up high so you can see where the Tv stations transmissions will light up the hills and valleys. You can then use this information so as with a antenna on roof of house can be pointed where the tv transmission is lighting up areas and receive the reflected signals , not all reflected signals are bad , in extreme situations it can be the best useable signal. . Some times the hottest signal will be close to the ground and close to the house.http://forum.tvfool.com/showthread.php?t=485 . http://forum.tvfool.com/showthread.php?t=410