What is the signal threshold for commercial skip/FF Thumbnails?

A while back I started having issues with thumbnails not being generated for (2) channels, as well as the recording length showing too short. I contacted support and they downloaded logs but I never got an answer. Since the 2 channels are owned by the same company and broadcast from the same location signal strength seems the most likely cause. However I never see any issues watching shows from those channels.
Now those channels never get commercial skip either.
In the Tablo app they both show 5 green dots. I disconnected the antenna from the Tablo and plugged it directly into my TV and it shows 3 bars out of 4.
What’s weird is that another channel that does get some occasional breakups always has thumbnails and commercial skip.

Here is a TV Fool link:

The ABC station is the one that doesn’t get thumbnails. It’s also the CW (40-2) but that doesn’t show here.

I have a roof-mounted antenna. I do have an amplifier and and an LTE filter installed as well.

How would you determine “signal threshold”? Arbitrary numbers like 4,6,8 or 10? The “green dots” are not dynamic. That is it’s not a continuous gauge of your signal, which varies.

It’s unlikely there’s an actual measurable break point as many have been asking for a long time for a way to measure signal strength from the tablo.

I guess what’s confusing is people always say that digital is different than analog. Analog declines more gracefully and with digital it’s either good or bad. And those channels always look perfect to me. The recordings never break up yet I don’t get thumbnails or commercial skip.

In the U.S., I thought ATSC was digital and NTSC was analog. And the U.S. switched from NTSC to ATSC in 2009. I don’t even have a T.V. with a NTSC tuner.

I’m not an engineer so I don’t have technical answers, I think it goes a bit deeper. Maybe resolution and number of sub channels. I have one stations which has a total of 4 sub channels (or 1 primary and 3 sub for a total of 4) Two of the subs are still HD 720p as well as the primary. That’s a lot of information compressed into that bandwidth spectrum.

On the sub channels at times you can tell it’s not the highest quality. It looks a bit distorted or lower res at times, put not pixelated which is often noticed with bad reception. Such things may or may not be a contributing factor.

You mean, the people who’ve talked to someone who knows, and now they know, but they forget exactly what they knew and paraphrase it a bit, but still… they know, so they’ll always say when they get a chance. You mean them people? :poop:

I have a strong degree of certainty you know that! As for analog, I recall something about LP or low power, but I don’t know if that’s digital or analog. Here’s a link from the foolish tv place, click on the radio button Only Analog and you’ll discover their existence.
[This site never seems as accurate for me as DTV Reception Maps]

I’m not sure about a specific tuner. My LG TV has options for DTV, TV, Cable DTV and Cable TV to choose from when scanning for channels.

Isn’t it all a question of HDTV versus SDTV. Where many call SDTV analog depending on 4:3 format versus 16:9, etc.

8vbs terrestrial and QAM would be considered a digital signal. And even though most cable providers have reassigned analog channels to broadband, most TV’s still support analog CATV and digital CATV.

An ATSC 8vbs digital signal would probably provide better signal quality then a n NTSC signal even for 480I.

I think I see, ATSC and NTSC just defined standards. Terms are often used interchangeably, and it’s commonly understood even if incorrect. I may have been lackadaisical following along, or keeping track.

I recall in the past discussing the difference between a static IP and an DHCP Lease Reservation. If someone actually hardwired their network, they’d have use a punch down block instead of a remote jack. However these are often intermixed and overlooked, incorrectly (that doesn’t make it right).

16:9 doesn’t equate to HD and I have yet to find any info that NTSC analog standards were 480i on old tube TVs. SDTV 480i appears to be a digital specification, despite the standard designation.
So I may have misunderstood.

At this point I’ll go back to the beginning and suggest there may be other factors negating the thumbnails.
From what I’ve followed here, those dots are of minimum value. More like a +/- for some. There isn’t any way to continually measure signal from tablo to set a threshold for any purpose.