Signal strength - what is stored?

I have been doing a scan almost daily to get the Tablo to store what I believe to be “normal” conditions. I have several rock-solid channels, several pretty good, and one or two weak channels.

My goal would be to have Tablo store as close to real-world as possible so that it chooses the most solid stations for recording.

When I scan, it seems like Tablo only ever finds five dots or zero. I’ve seen one dot before but nothing in the middle. This morning I’m getting all-five. However when looking through another utility there is quite a variability in signal quality amongst those 5-dot stations. Is Tablo storing this scan as all-fives and therefore giving equal priority to the channels, or is it storing a more granular number that takes into account that (for example) WUTV has a signal strength of 63% and CFTO has a signal strength of 91%?

My reality is that CFTO will almost always be solid, but depending on time of day WUTV may drop signal quite a bit. I’d like to know that the recording logic takes that into account, which is why I keep scanning to try to find a scan that matches my reality (but not having much luck).

If two channels have the same show and you choose record new as an example, the Tablo will record from the channel that has the best signal strength.

The strength is based on whenever you did your lady channel scan. The strength is static, it is not dynamic on live changes in strength. This generally works well for most people because the strength is pretty consistent.

Understood. To clarify, is that signal strength stored as a 1-5 value as shown in the ui (in which case all mine are equal) or is it stored a more fine-grained number that recognizes that there are in fact differences between the channels regardless of what is show in the scan UI.

@pnear - The signal is stored more as a zone vs. a percentage based on how many errors are present.

5 dots means excellent reception: any errors can be corrected.  3 dots means good reception: many errors can be corrected. 1 dot means many errors that cannot be corrected: generally unwatchable.

If you check out this graphic you’ll see the straight portion of the digital signal is where it’s good. This is where you’ll see 5 dots. Once you get into the curved portion before the cliff, you’ll see that as a 3 dot. Anything just beyond that will be 1 dot.

When it comes to selecting one channel over another, the priority is based on: signal strength, then resolution (vertical and horizontal), then aspect ratio (16/9 preferred over 4/3), then the major channel number (to break ties). Channels with higher numbers generally have less interference so they get selected first. 

As @theuser86 said, the scan is not dynamic. 

Hope this helps explain things for you.

When evaluating signal strength to choose a channel, are all five-dot “excellent” channels evaluated as equal strength?

Yes they are. 

Thanks, I will use that knowledge to make sure I save a scan that is reflective of the usual conditions.


No problem Pete. Glad we could answer your questions.


I made this request in October to let us choose the channel for smart recording - it would fix your problem. It is on the to-do list: