Television Channel Signal Strength Table

This is an exercise I completed for my own edification and reference. It may serve as an example for others and be of benefit to them as well. That is why I am submitting this post.

For those who may have a television that can display signal strengths for various channels you may want to build a table such as I have done below. The readings were not taken right at the Tablo itself but do give me an idea what the conditions might be and how the signal strengths of the various channels vary. If I try using an attenuator in the line then I would want to check the weakest signal channel first to see if the video quality was still acceptable.

These readings are for television stations I receive in Knoxville, Tennessee.
Hope this helps someone.

6.1 WATE 94
7.1 WKNDHD 94
7.2 DAYSTAR 94
8.1 WVLT-DT 72
8.2 MYVLT 72
10.1 WBIR-HD 90
10.2 WBIR-ME 90
10.3 WBIR-JN 90
14.1 W14CX-D 78
14.2 3ABN-PR 80
14.3 3ABN-DD 80
14.4 3ABN-ES 80
14.5 3ABN-PR 78
14.6 3ABN-PR 78
14.7 3ABN-PR 78
15.1 WKOP-HD 78
15.2 WORLD 80
15.3 CREATE 78
20.1 WBXXCW20 84
20.2 ESCAPE 74
24.1 WDTT 84
24.2 WDDT 86
43.1 WTNZ-DT 90
43.2 BOUNCE 90
43.3 GRIT 90
45.1 W45DF-D 55
48.1 WVLRDT48 74
54.1 ION 88
54.2 QUBO 90
54.3 IONLIFE 88
54.4 SHOP 88
54.5 QVC 90
54.6 HSN 88

I’m curious about the relative signal strength reading. Relative to what? If it’s to each other, seems there should be at least one that’s 100 (percent, I presume). I don’t know if my tv has a signal strength reading, but I have a cheapish DVR (Homeworks 150) that gives me a reading, and it’s always in ‘percent’, but I don’t really know what that means. I wonder if the ones that read 100% may have a possibility of being over-driven. I know I’ve had a couple of instances where a recording got corrupted, supposedly by a bad signal, but it’s on a channel that shows 100% strength.

Signal strength and SNR are not constant. They vary from moment to moment. A channel can be getting 90% at 2:01 PM and 85% at 2:15 PM. Environmental conditions change over the course of a day. Seasons and the time of day affect signal strength and quality. A signal can dip as much as 20% in the course of a day.

Signal strength and SNR (signal to noise ratio) are not the same thing. There is one channel on which I get 95% signal strength but can see a host of packet errors that affect the SNR.

To mitigate signal fluctuation, I installed a horizontal stack of two antennas. If the signal at one antenna degrades, the signal at the other antenna may remain constant and temper the loss of the other antenna’s reception. I quit relying on the vagaries and quirks of one antenna years ago…

Reception measurement is relative to the tuner one has. My LG tuner is superior to my Hauppauge tuner. 85% signal strength on my Hauppauge is 100% on my LG.

One way generating this list helped me is I just compared it to my Tablo channel scan and found three channels that did not get detected on my last scan. Perhaps the signal strength on those particular channels were low at the time.

Time to re-scan. Will try with my existing -7db attenuator in the circuit, and if that does not pick up the missing channels, will go to full strength or try another output from my distribution amplifier.

I do my channel scans between 7 and 9 at night. That is when my signals are strongest and most stable. Since this is when we do our viewing, this is the time for Tablo to detect the required channels.

For example, ION, which is 85 degrees off axis from all the other channels, is picked up only at night. The Tablo detects it only at that time during its scan. (One day I will install an antenna to point in that direction to get ION all day.)

I re-scanned and picked up the missing channels (I made certain I deleted all previous schedules before I re-scanned in case the scheduled recordings were linked to a channel look-up table that would change after new channels were added).

All channels showed five green dots; even the ones that I did not pick up before.

I discovered my attenuator setup most likely did not work. I went back and put it in-line at the television receiver I used to generate the table at the beginning of this thread and did not see any reduction in the signal strength. I will have to go back to the drawing board trying to see a relationship between “Loading…Please Wait” messages with a Tablo Roku app and TV channel signal strength.

I also added TV resolution to the table I generated earlier (like 720p (16:9), 1080i (16:9) 480i (4:3) ) and may eventually be able to see a correlation between excessive LPWs on a recording and the actual TV station broadcast resolution.