Testing tvfool and antennaweb for accuracy

1inxs

DTVUSA Member
#1
I thought I'd start a thread to test for the accuracy of websites like TV Fool
AntennaWeb
Antennapoint.com - Antenna Locator
I have learned from other posts some of these websites are all volunteer. Hopefully we will help with the accuracy through information users will post in this forum. My Zip Code is 84036. What channels can I expect to receive? What antenna is recommended and what direction do I need to aim it? What will happen after the DTV transition? Please post back with the website used and what the recommendations are. I will post back with my results.
 

ercjncpr

DTVUSA Member
#2
My zip is somewhere in southern California (sorry, I am too paranoid about internet privacy to be more specific than that) and TV Fool has worked great for me on all but a couple channels. I would advise those viewers in the
"June 12th areas" to try it AFTER the transition. You might notice that it was more accurate than you think.
 

Piggie

Super Moderator
#3
I thought I'd start a thread to test for the accuracy of websites like TV Fool
AntennaWeb
Antennapoint.com - Antenna Locator
I have learned from other posts some of these websites are all volunteer. Hopefully we will help with the accuracy through information users will post in this forum. .....
The only one that is volunteer is TVFool.com run by Andy Lee.

He can be contacted with corrections and ask him questions and if you lurk the last few pages learn a lot how the site works

Official TV Fool forum - Page 17 - AVS Forum

That is the current page the thread is up to at this point.
 

1inxs

DTVUSA Member
#4
The only one that is volunteer is TVFool.com run by Andy Lee.
My post wasn't to figure which of the websites was volunteer. I posted to see based on the best websites available, what stations/channels I can hope to receive before and after the DTV transition. Mostly to prove a fact. I was only able to determine my antenna and direction of tower by driving around a 3 county area and contact the county engineers. I may not completely understand tvfool and the others. They gave me no information relevant to my area. I wonder how inaccurate they are in other areas. I see numerous posts using information to choose the type of antenna and which direction to aim for the best reception. I posted my Zip of 84036 and challenged others to confirm the accuracy of the websites.
 

otaota

DTVUSA Rookie
#5
I posted my Zip of 84036 and challenged others to confirm the accuracy of the websites.
The main problem with your request is that zip code 84036 is very large and the centroid of the zip code is in the middle of nowhere. Searching for zip code 84036 in Google Earth yielded a point that was deep in the mountains about 30 miles from the nearest transmitter. There is definitely very little TV signal reaching this point, so that is probably why the tools didn't provide you with any useful information.


In this kind of environment, you'll need to be much more specific with your location in order to get a realistic result. You'll probably get much more useful feedback from those sites by entering your exact address or coordinate.

Cheers,
Chuck
 

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1inxs

DTVUSA Member
#6
Welcome to the DTVUSA Forum and thank you for your post. I can see 3 cities on the map you posted. I am in Kamas, the city in the center of the 3 cities shown.
The main problem with your request is that zip code 84036 is very large and the centroid of the zip code is in the middle of nowhere. Searching for zip code 84036 in Google Earth yielded a point that was deep in the mountains about 30 miles from the nearest transmitter. There is definitely very little TV signal reaching this point, so that is probably why the tools didn't provide you with any useful information.


In this kind of environment, you'll need to be much more specific with your location in order to get a realistic result. You'll probably get much more useful feedback from those sites by entering your exact address or coordinate.

Cheers,
Chuck
 
#7
Antennaweb.org is more accurate at my end, TVFool misses one channel that is new to my area, but thinks WAZE-TV is there when it ain't. Antennaweb.org shows no mention of WAZE-TV because, as fact sadly states, it doesn't exist outside of cable/satellite. i was afraid of that, bye bye one of my favorite channels, those of you with a CW affiliate be very thankful, i just lost mine.
 

Trip

Moderator, Webmaster of Rabbit Ears
Staff member
#8
I may not completely understand tvfool and the others. They gave me no information relevant to my area. I wonder how inaccurate they are in other areas. I see numerous posts using information to choose the type of antenna and which direction to aim for the best reception. I posted my Zip of 84036 and challenged others to confirm the accuracy of the websites.
You live in an area served only by translators. When you look at the number of stations in the state of Utah, there is no way to list them all unless you want to turn it into a full-time job. Observe:

W9WI.com/TV Database Online/(states)Utah

I started trying to sort out the translator network in Utah one day, spent about 4 hours on it, and then gave up. It's way too complicated. Andy would likely handle it better than anyone else, but as I said in another post, he can't be expected to know what every one of the 4,000 full- and low-powered stations in the country are doing, especially each translator in Utah. Your inaccurate results from the various sites is an exception, not a rule.

Antennaweb.org is more accurate at my end, TVFool misses one channel that is new to my area, but thinks WAZE-TV is there when it ain't. Antennaweb.org shows no mention of WAZE-TV because, as fact sadly states, it doesn't exist outside of cable/satellite. i was afraid of that, bye bye one of my favorite channels, those of you with a CW affiliate be very thankful, i just lost mine.
I have answered this in another thread.

- Trip
 

divxhacker

DTVUSA Member
#9
You'll probably get much more useful feedback from those sites by entering your exact address or coordinate.
Cheers,
Chuck
I wonder when they will use Zip Plus 4 or Plus 6, that can home in on the exact area. (you can see your plus 4 or plus 6 code on some bills you receive. You'll notice the plus 6 is the address' last 2 digits added to the plus 4)
 

Piggie

Super Moderator
#11
I wonder when they will use Zip Plus 4 or Plus 6, that can home in on the exact area. (you can see your plus 4 or plus 6 code on some bills you receive. You'll notice the plus 6 is the address' last 2 digits added to the plus 4)
Andy's site, TVFool.com you can use latitude and longitude and it's even more accurate than street address more so in rural locations.

To find your Lat / Long go here:
Google Maps Latitude, Longitude Popup and find your lat and long

Then go to TV Fool and click the radio button saying Coordinates and copy and paste from the map to TVFool

You will then be assured a more accurate location. The TV towers are entered by lat and long so it's a little better than a street address.


If you have ideas for TVFool, here is the place to post them addressed to Andy S Lee.
Official TV Fool forum - Page 17 - AVS Forum

You would also have to ask Andy what database he uses to find locations. It's very possible it doesn't use 9 digit zips to pinpoint a location. 9 digit zips are mainly to pinpoint a specific address. Maybe in an apt building more than one address shares a 9 digit zip, I don't know.

But it would seem a database if it used 9 digit zip would be no more accurate than a street address, as basically they are one in the same.
 

Piggie

Super Moderator
#12
Tvfool has more data than antennaweb but I can't make head nor tails of it
Andy goes to great lengths to explain his site in the Official TV Fool Thread over on AVS Forum.

If you start at the last page and look back through time, he does some great tutorial through out the thread.

Official TV Fool feedback forum Official TV Fool forum - AVS Forum

Updates (17-May-2007) Official TV Fool forum - Page 2 - AVS Forum

Updates (13-May-2007) Official TV Fool forum - Page 2 - AVS Forum

28-Oct-2007 Added Compass Readings to Radar Plots Official TV Fool forum - Page 4 - AVS Forum

A Discussion about Longley-Rice Official TV Fool forum - Page 5 - AVS Forum

Updates to TV Fool Signal Analysis Official TV Fool forum - Page 7 - AVS Forum

Format of Signal Analysis report has changed (NEW!) Official TV Fool forum - Page 9 - AVS Forum

Visual explanation of Noise Margin Official TV Fool forum - Page 14 - AVS Forum

These are just his labeled informational posts. The wealth of knowledge on TV propagation in that thread is invaluable.
 

1inxs

DTVUSA Member
#13
My main reason for starting this thread was to get this type of information out there. I have seen a lot of posts that assume tvfool or other websites are going to help aim every antenna and list every station. It seems you are the most up to date and knowledgeable on the subject, which I appreciate a lot. I find with a combination of tvfool and antennapoint, as well as the information from county engineers, we here at DTVUSA will better serve others with their OTA reception problems. Antennapoint is a good website for visualizing the location of towers or translators. High power are green and low power are red. I have used the map to physically drive to the translator site and verify it's position. Once you know the county the translator is located, you can contact the county engineer to find what is broadcast and on what frequency. I have posted this information and others here in the forum have dismissed this option and seem to think tvfool is all they need to answer everybody's question. I just don't want anyone here to think they can use a generic answer for every situation. If you look at antennaweb, it would have me aim my antenna at the Salt Lake Valley. The translators in Salt Lake are 47 miles through 3 mountain ranges. I know from my profession and personal experience Utah is a huge challenge when it comes to OTA reception. I've been installing C-band satellite systems and rooftop antennas for over 30 years. Now you say Utah is the exception rather than the rule. Are there other States you have found to be similar to Utah? I believe I read a post here in a thread that said you are interested in improving tvfool. Could you post Utah and the other similar areas in the forum here and on your tvfool. That would be my request if your asking for input. I didn't want you to think I didn't support tvfool. Again I appreciate your hard work and the help you offer to others here as well.
You live in an area served only by translators. When you look at the number of stations in the state of Utah, there is no way to list them all unless you want to turn it into a full-time job. Observe:

W9WI.com/TV Database Online/(states)Utah

I started trying to sort out the translator network in Utah one day, spent about 4 hours on it, and then gave up. It's way too complicated. Andy would likely handle it better than anyone else, but as I said in another post, he can't be expected to know what every one of the 4,000 full- and low-powered stations in the country are doing, especially each translator in Utah. Your inaccurate results from the various sites is an exception, not a rule.



I have answered this in another thread.

- Trip
 

otaota

DTVUSA Rookie
#14
Antennapoint is a good website for visualizing the location of towers or translators. High power are green and low power are red. I have used the map to physically drive to the translator site and verify it's position. Once you know the county the translator is located, you can contact the county engineer to find what is broadcast and on what frequency.
Have you seen the transmitter mapping tool at TV Fool? HINT: Enable the checkbox called "Show lines pointing to each transmitter". It also shows local transmitters on a map for you to explore, and has some key differences:

1) It only shows transmitters you have a chance at receiving. Transmitters behind three mountains or otherwise too weak to receive won't be shown. There's no point trying to figure out channels you have no hope of receiving.

2) You can adjust the location and altitude of the point being analyzed. The display updates automatically when you change anything. This lets you adjust for inaccurate address lookups and play all kinds of interactive "what if" games.

3) You can also browse coverage overlays for individual transmitters. This helps you get a feel for how the signals get chopped up by the terrain. These are real propagation modeling maps, and not just the over-simplified service contours you get from the FCC.

4) You can switch between different map views (e.g., terrain, satellite, roads, etc.). If you zoom all the way in on most transmitters (in satellite view), you'll actually see that TV Fool is usually more accurate than other sources.



I fully agree that any and all web resources should be shared and used. For each type of resource, it's important to know its strengths and weaknesses so that you don't get misled by incorrect inforamation. No resource is immune from errors/bugs (including the FCC), so it's always a good idea to cross-reference multiple sources for data.

Other useful places not yet mentioned in this thread are:

FCC TV Query (the original source of everything)
DTV Maps (also done by the FCC)



Cheers,
Chuck
 

1inxs

DTVUSA Member
#15
Chuck, Thanks for the information. When I go to tvfool it tells me my channels are from the Salt Lake Valley. But the lines on the map are non existent for the tower tvfool lists the stations for. Every website tells me to aim my antenna through 3 mountain ranges 48 miles away to receive the digital signal. I have never tried that because I believe it is impossible. I am located at Kamas, Utah 84036. What antenna is recommended? What compass heading should I use? I'll be extremely grateful if the information I receive is successful in receiving DTV from the Salt Lake City, Utah broadcast area. They have many more channels than I do up here.
Have you seen the transmitter mapping tool at TV Fool? HINT: Enable the checkbox called "Show lines pointing to each transmitter". It also shows local transmitters on a map for you to explore, and has some key differences:

1) It only shows transmitters you have a chance at receiving. Transmitters behind three mountains or otherwise too weak to receive won't be shown. There's no point trying to figure out channels you have no hope of receiving.

2) You can adjust the location and altitude of the point being analyzed. The display updates automatically when you change anything. This lets you adjust for inaccurate address lookups and play all kinds of interactive "what if" games.

3) You can also browse coverage overlays for individual transmitters. This helps you get a feel for how the signals get chopped up by the terrain. These are real propagation modeling maps, and not just the over-simplified service contours you get from the FCC.

4) You can switch between different map views (e.g., terrain, satellite, roads, etc.). If you zoom all the way in on most transmitters (in satellite view), you'll actually see that TV Fool is usually more accurate than other sources.



I fully agree that any and all web resources should be shared and used. For each type of resource, it's important to know its strengths and weaknesses so that you don't get misled by incorrect inforamation. No resource is immune from errors/bugs (including the FCC), so it's always a good idea to cross-reference multiple sources for data.

Other useful places not yet mentioned in this thread are:

FCC TV Query (the original source of everything)
DTV Maps (also done by the FCC)



Cheers,
Chuck
 

Piggie

Super Moderator
#16
..........I believe I read a post here in a thread that said you are interested in improving tvfool. Could you post Utah and the other similar areas in the forum here and on your tvfool. That would be my request if your asking for input. I didn't want you to think I didn't support tvfool. Again I appreciate your hard work and the help you offer to others here as well.
It's not my TVFool, it belongs to Andy S. Lee

Andy is not a member of this forum I am aware of.

If you have suggestions I suggest you go to AVS forum and address improvements to him directly.

=======

Why do I defend Andy and TVFool ?

When I got started helping myself and others with DTV there was only anntennaweb.org. It lead me to a lot of wrong conclusions, most as it's too conservative.

Andy started building TVFool in April of 2007 seeing a need for a better site, just like those here are all trying to help people. I was so glad he built it. It made life much better.

He has polished his site until it appears big gun commercial, but it's just him. I think he has become so popular and polished his site to be big enough to be questioned and a target.

Maybe it's the personal touch, reading his thread over the years seeing the improvements.

Utah is much of a special case. Did you see that list of translators compiled by W9WI? That is HUGE.

If I put your address in zip code in AntennaWeb.org, I only get full power stations. If I put your zip in TVFool.com I get a lot of translators in analog post transition, no they are not HD or even DTV. How accurate are Andy's list of translators near your zip code? I don't know, W9WI has become the expert on translators in that area and he can't keep up.
 

otaota

DTVUSA Rookie
#17
When I go to tvfool it tells me my channels are from the Salt Lake Valley. But the lines on the map are non existent for the tower tvfool lists the stations for. Every website tells me to aim my antenna through 3 mountain ranges 48 miles away to receive the digital signal. I have never tried that because I believe it is impossible. I am located at Kamas, Utah 84036.
Entering Kamas, UT into TV Fool yields the following map.



From the looks of the terrain, it seems like the marked transmitters do have a chance of reaching the point under the marker. It doesn't seem to be showing any transmitters that are completely unreachable.

This map was for an arbitrary point in Kamas. If you use your exact address or use "satellite" view and drag the marker right on top of your house, you'll get a more precise reading for your location.



What antenna is recommended? What compass heading should I use? I'll be extremely grateful if the information I receive is successful in receiving DTV from the Salt Lake City, Utah broadcast area. They have many more channels than I do up here.
The radar plot for the arbitrary point in Kamas is available at tvfool.com...id%3d249db08b30ac21. Click the radio button next to "Post-transition: All Channels" to see a summary of all analog and digital transmitters within reach.

Note that the FCC has intentionally focused on full power major broadcasters for this step of the DTV transition. They have not been processing DTV applications for translators, boosters, and other low power transmitters so that more attention will be focused on the major broadcasters and the June 12 deadline.

It is expected that a lot of the translator and booster stations will switch to digital operation at the same time or shortly after the June 12 deadline, but none of that information officially shows up as "digital" transmitters in the FCC database. This means that you'll need to pay attention to the post-transition analog translators and boosters for now (some of them might already be digital, and others soon will be) with the expectation that some or most of them will be converted to digital over the next few months.

There are about 1,800 major broadcasters that are being scrutinized by the FCC right now. There are about 5,300 low power transmitters in use. About 2,100 of these have already been granted permission to build digital facilities by the FCC, but they are not subject to the same June 12 deadline. Many of them are expected to switch shortly after June 12, but the FCC has not been strict about dates for them.

Since the FCC still only shows these records as analog transmitters, you'll need to pay attention to the analog transmitters in the TV Fool reports until the FCC database get updated with proper DTV records.



In regards to the best antenna for yourself, it would be helpful to have the TV Fool analysis done for your exact location (the generic Kamas analysis might not be representative of your exact location due to all the terrain effects).

If your location is like the generic Kamas case, then it looks like most of your local stations fall into two major groupings. One group is in the north-west (about 312 degrees on a compass), and the other group is in the south (about 150 degrees). FYI, all maps are printed with "true north" orientation, while all compass readings must reference magnetic north azimuths (TV Fool provides both numbers for you). There are a few stations in other directions, but they are weaker and probably unnecessary if you can get most of your major stations from one of the stronger channel clusters.

Almost all of these transmitters are on UHF. K08IE, K10JB, K12JM, K03HQ, and K06JH are the exceptions. If you don't care or need any of these stations, then you could go with a UHF-only antenna (smaller, lighter). If you care about any of the VHF stations, then you'll need to include VHF capabilities in your setup (generally much larger antennas).

Since the stations are in two different clusters (assuming the other clusters are not that important), you can use two antennas with an A-B switch, you can use one antenna on a rotator, or you can use two antennas through a combiner. The last option reduces the signal strength across all channels, but it avoids the need to adjust anything when watching different channels (or if you have multiple TVs, or if you want to use a DVR to record shows).



Any more specific advice will depend on your exact TV Fool analysis plus your feedback on how important any of the VHF stations are.



Cheers,
Chuck
 

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