How to Estimate TV Reception in Your Area

Chicago TV signal map

The most common questions readers ask me are “how many channels will I be able to receive?”, and “what kind of antenna should I get?”

These are not easy questions to answer. I wanted to take a moment to explain some of the factors affecting your TV reception so you can make some better estimates of how many channels you’ll be able to get with an antenna, and how you can improve your reception.

How TV Signals Propagate

In an ideal flat world, TV signals would radiate in a perfect circle outward from the source. The strength of the signal would just depend on how far you were from the transmitter.

But, the real world can be bumpy with all kinds of hills, mountains, and valleys. I did some analysis using an online tool at the TVFool.com website to determine how much effect these terrain features have on your TV signal. The answer is that they have a huge effect!

First, let’s take a look at a super flat area like Houston, TX which is the ideal case:

Houston, TX TV reception
Coverage map of Houston, TX from TVFool.com

Signal Strength Legend

The colors indicate how strong the TV signal is, from white to red to green to blue and purple.  Note how the signal radiates in an almost perfect circular “target” pattern when the land is flat.

How Terrain Affects TV Signals

Okay, Houston is an ideal case. Let’s take a look at some whacky terrain and see what effect it has on the signals.  Check out Boston, MA:

Boston TV signal strength map
Coverage map of Boston, MA from TVFool.com

Boston has some mild hills, and you can already see that the perfect circular pattern is very distorted, and that there are little valleys where the TV signal is weak. If you happen to live in one of these valleys, your reception will be poor.

Next, let’s take a look at my home town of Los Angeles, CA, which lies in the basin between some fairly large mountains and a really crazy pattern:

Los Angeles TV signal strength map
Coverage map of Los Angeles, CA from TVFool.com

You can clearly see that the signal is pretty much stopped in its tracks to the north, where the mountains are.  Also, you can see purple “shadows” where the smaller mountains are blocking the signal.  Interestingly, there is a “shadow” just to the south of the transmitter where the mountain itself blocking the signal.  In that area, the people live only a few miles from the transmitter, but are getting a very weak signal!

Let’s take a look at San Francisco now:

San Francisco TV signal map
Coverage map of San Francisco, CA from TVFool.com

This shows another crazy pattern.  The transmitter is located on the famous Sutro tower on Twin Peaks.  If you have a line of site to the tower, you’re in good shape, even if you’re way across the bay in Oakland or even Berkeley.  But, if you live in South San Francisco, you’re screwed because mountains are blocking the signal.

These maps show how much terrain affects TV signals.  Even if you’re really close to a transmitter, if you are in the “shadow” of a mountain or hill, your signal might be weak.

On the other hand, if you live in a flat area with nothing blocking the signals (like across a span of water), you might be able to get good TV reception even from very far away.

As informative as these maps are, however, they are limited because they do not take into account buildings, trees, and other features that might block your signals.  New York City looks great “on paper”, but if a skyscraper is between you and the TV tower, you could be in bad shape.

This is why it’s so hard to predict how many channels you’ll be able to get.  Someone who is 70 miles away might get better reception than someone who is 10 miles away, due to the terrain or objects blocking the signal.

How to Check Your Location

You can use this tool to check any station in your area.  Find the call letters of the station you want to check.  If you don’t know them off hand, go to the Station Finder, or AntennaPoint and enter your location to see a list of stations and their call letters.

Next, go to TV Fool’s Online Coverage Map Browser Tool and enter the call letters of the station.  Click “Search”, and a colored “heat map” will appear showing signal strength.  You can zoom in to find your exact location.

What Kind of Antenna to Get

The colors in the map will tell you what kind of antenna you need.  White is the strongest, then red, then, orange, then yellow, then green, then blue, then purple.

If you are in a green or stronger area, you should be able to receive that channel with a good indoor antenna like the Mohu Leaf.

If you are in a blue area, you should be able to receive that channel with an attic or roof antenna.

Anything further out – you might be able to get with a roof antenna, but no promises!

Signal Strength Legend

One caveat is that VHF signals are more difficult to receive (by most HD TV antennas) than UHF signals.  So, even if a VHF station is “green”, you might not be able to receive it with an indoor antenna.

Another factor you’ll have to consider is whether the TV signals in your area are all coming from the same direction or from different directions.  In Los Angeles, all of the TV signals come from Mt. Wilson, so I can use a unidirectional antenna pointed in that direction.  If the signals are coming from different directions in your area, you’ll want to use an antenna that is more omni-directional.  I’ll talk more about this in a future article.  For now, the Mohu Leaf does a pretty good job of receiving signals from different directions, although most antennas are somewhat directional, including the Leaf.

How to Improve Your Reception

These maps show how important it is to have a direct line-of-sight to the transmitter.  Any objects in the way will literally cast a shadow where the TV signals are weak.

The way to somewhat improve this situation is to put your antenna up as high as possible. The second floor is better than the first.  The attic is even better.  The roof, even better.  Of course, if you have a 10,000 foot mountain in the way, putting your antenna on the roof probably won’t help, but you can make the call based on the coverage map and the obstacles in your immediate area, whether it’s worth the effort or not.

Another super important thing you can do based on these maps is to point your antenna towards the transmitter tower.  Figure out the compass direction and point your antenna accordingly.  If you need to run a longer cable in order to do that, it can be well worth it.  You want to have the antenna on the side of your house that faces the signals.

An amplified antenna might help if all of your signals are far away.  If some are close and some are far, it can actually hurt your overall reception, because the stronger signals will swamp your amplifier and drown out the weak signals.

Conclusion

I hope these maps have helped you understand how much of an effect terrain and other obstacles can have on your TV reception. Here is the full list of cities that I looked at:

Please feel free to post the map of YOUR area below, and let us know how many channels you are getting! – Brian

  • JKM N MD

    Brian, hello. We reside outside Washington DC in zip code 20878. We have a 2nd floor condo in s garden style building located in a shallow valley surrounded by woods. We purchased the GE UnltraPro Stealth HD Antenna that has 60-miles range. Inside we have better reception than anticipated with most of the TV station in the DC area but not all and none from Baltimore. However, we would like to discreetly locate the antenna outside on our balcony, which faces south, southwest at 215 degrees but are able to point the antenna in any direction needed to maximize the signal. The exterior construction is wood with aluminum studying used for interior walls. Eventually, once we have this antenna working, we would like to have the antenna work for whole condo but for now focusing on obtaining the best possible signal on one TV.

    • Cool, thanks for sharing! Let us know how it turns out! If you want to drive the whole condo you might need an amplifier.

      Best,
      Brian

  • Gene Sky

    Gene Sky , Date 07-07-2016

    Go to http://www.tvfool.com , Help With Reception , Digital Broadcast Tv Reception.

    Also you can go to , http://www.ftalist.com . FTA = Free To Air Satellite Tv. Many Networks can be received for Free. All of the PBS Networks and more networks.

  • Dusteyrose

    Thank you for your informative article! I’ve been cord free for 3 years using a Radio Shack amplified antenna. At the moment, I use it with my new smart TV in my living room. I also have a small 8 year old TV that can also be used as a computer monitor. I want to put it in my bedroom so I connected it to my amplified antenna to see if I would get any channels in my bedroom. To my surprise I got zero channels! This is shocking because my bedroom is directly next to my living room and their windows both face the same directions. I get 26 stations on my smart TV in my living room. I had the antenna next to the window, facing the same way in my bedroom as is faces in my living room. I have to assume that there’s something going on with the old TV because the problem isn’t the antenna. Can you tell me why I get no channels on the 8 year old small flat screen TV/monitor in my bedroom and how to remedy that problem?

    • Hi Dusteyrose,

      That is somewhat surprising. If your old TV definitely has a digital broadcast tuner, then it might not be as high quality as your smart TV. Also, make sure you went through the digital channel scan process properly.

      Best,
      Brian

      • Dusteyrose

        Hi Brian, Thank you for your speedy reply. I just realized I stated my problem incorrectly, so sorry! That’s one of the problems of being electronically illiterate. Your reply jolted some sense into my brain. Apparently the TV/monitor is lacking a digital broadcast tuner because there are only two channel input options which are TV and Cable, there is none for antenna. I guess my only use for the old TV/monitor is watching DVD’s if I can find an RCA cable because it has no HDMI. Either that or use it as a huge paperweight! Thanks again!

        • OK, glad you figured it out!

          Best,
          Brian

  • Falcon

    We live in the 28906 zip code, far west end of Cherokee Cnty, NC. We’d love to ditch the satellite, but I’ve looked at TVFool data, and my best estimate is that likely no stations could be captured OTA. We could easily mount an antenna upwards of 40 feet on the roof, but…mountains and more mountains. We’ve been talking a lot about just cutting the cord and relying on DVDs for any TV viewing.

    • Hi Falcon,

      Yeah, sorry, it doesn’t look like there are any broadcast TV signals in your area. In addition to DVD, you can find some free content on the Internet. I actually watch a lot on YouTube.

      Best,
      Brian

  • Tate

    I live about 2 miles from the broadcast towers of all the major networks, but not in a city with lots of tall buildings (Needham, MA, 02492.) In the maps from this site I am practically in the white colored center. So, I was expecting no signal problems whatsoever even though the antenna would be on the first floor. However, the night I hooked up the Leaf it was snowing and windy and the signal was cutting out and barely watchable on a couple of the channels. Today the weather is better, but when a commuter train goes by or I walk in a certain part of the room I still get a couple pixelation cut-outs. So, I guess I need to go up. This a bummer since that is not going to be that easy.

    My question is whether I should be trying the Moho Sky 60 or just use the Leaf 30 I have in the attic. Being so incredibly close I guess this has to be an interference issue, but I don’t know if the 60 would be any better overcoming that. Before I start drilling holes to get to the attic I just trying to make sure I have the best plan. I also want to make sure i have the most rock-solid coverage I can.

    • Hi Tate,

      Before buying a new antenna or drilling any holes, I would just try the Leaf 30 in the attic. Basically, do as much experimentation as you can with your existing antenna before spending money on a different antenna.

      Here are more things to try: http://disablemycable.com/blog/antenna-tips/

      Best,
      Brian

  • Dave

    The New York City map shows the signals coming from the World Trade Center. That was true until September 11, 2001. Since then, the TV transmitters have been at the Empire State Building at 34th and 5th. The new 1 World Trade Center tower is trying to lure the TV station to move their transmitters down there, but it hasn’t happened yet.

    • Hi Dave,

      Thanks for the info!

      Brian

  • Elizabeth

    I can get you the lowest prices DirecTV or Dish. I can also help with Charter, Time Warner, Dish Net, Hughes Net, AT&T, Century Link, etc…. Email me at 1stchoicesolutions2015@gmail.com.

  • PV

    Hello Brian,

    Need your help. My zip is 97229. I recently moved from an apartment to a new home. At my apartment, I had a Winegard Flatwave Amped FL5500Y which I got from Costco, working great. My new house is on a downhill slope on a East (low) – West (high) street. Being the western most corner lot, it has a row of homes, each progressively higher than the other, towards the east, which is the direction (East SE) towards the towers. Basically, I am in a hole and get nothing. I went to Best Buy and they suggested trying the Clearstream Micron XG and the 2V. Still no luck. All 3 pull in just 2 channels. I have tried moving them around inside (including upstairs) but without any luck. The Clearstream support guy thinks that some shielding or the fiber cement exterior is blocking all signals. Do you have any suggestions on what I should try. I am dreading having to pay for a cable connection just to watch local channels.

    Thanks in advance.

    • PV

      To correct my previous note. My street slopes from East (high) to West (low).

    • Hi PV,

      In general, I don’t recommend buying a lot of different antennas; usually getting a different antenna doesn’t solve the problem.

      It is possible that your particular building walls are blocking the signal. As an experiment, try putting your antenna outside through a window or open door to see if reception improves. Outside on the second floor would be best (you might need a longer cable).

      If that does help, you might have to figure out a way to mount your antenna outside.

      It is also possible that the sloping hill is blocking the signals. In that case, there’s not much you can do other than to put your antenna as high as possible to get line-of-site to the transmitter towers.

      You might also want to ask your neighbors what kind of reception they are getting to see if anyone else was able to solve it.

      Best wishes,
      Brian