Tablo fails to find channels my TV's receiver finds

I am new to Tablo, I just received and installed my Tablo on 09/27/2016. I am wondering why my Tablo isn’t finding all of the channels my TV’s find. I know it isn’t an issue of signal strength because of the following observations: All comparisons are made with the antenna connected to just the TV, using its tuner vs the antenna connected directly to the Tablo. There are no splitters in the system. I am using the same antenna connected straight to my HDTV or straight to my Tablo. The antenna is fixed and is on my roof.

Tablo does find channels 57-1 (KXTUCW) and 57-2 (Mundo) which it shows clearly yet my HDTV (finds them) but they are fuzzy. This would imply that the Tablo tuner is better than my TV tuner.

Tablo does not find channels 51-1 (KWHS 51) or 51-2 (KWHS 51 COZI). My HDTV finds these channels and they are crystal clear.

So why does Tablo find channels that are so weak and display them clearly when my HDTV alone can find them but barely display them yet my Tablo can’t find channels that my HDTV finds and displays clearly? As stated above, I am using the same antenna, in the same place, connected directly to my HDTV versus connected directly to my Tablo. There are no splitters in the system. There is not an amplifier in the system. I have tried entering different zip codes to see if that makes a difference and it does not. The Tablo web site says that the zip code is used only for channel guide information. I concur that this is the case because whether I enter my actual zip code, surrounding zip codes or a zip code 2,000 miles away the Tablo finds the same channels.

I live in Colorado Springs, Colorado 80920.

I thank anyone and everyone (other users or Tablo representatives) in advance for any help or insight you can provide.

Interestingly, I just recently lost my Cozi TV channel.

My Tablo Quad used to pick up…
Channel 15.1
K15CU
Cozi TV

It plays mostly vintage shows, like The Munsters, and The Dick Van Dyke Show, …
Eventhough my Tablo did successfully tune into this channel for many months, now it can’t.

I tried rescanning for channels, and now K15CU doesn’t even show up in the list.
My antenna didn’t move, either.

It’s possible that those channels aren’t in the guide database and need to be added. I would create a ticket with the Tablo folks to get them added (if that is indeed the issue).

Snowcat, Thank you for the information. How do I create a ticket?

http://support.tablotv.com/hc/en-us/requests/new

Even if not in guide if it finds them, they list the stations. Remember me asking about Buzzr, Cozi, Grit, Laff, etc when i even knew the dates the new stations were coming. Just no guide data, but if detected they are there.

Hate to say it, but I suspect Tablo tuner is bad.

Beastman, Let me make sure I understand I what you are saying. Since I know the stations exist because my HDTV (three different ones) pick up the stations (and they are very strong). The fact that the Tablo doesn’t pick them up indicates it may be bad. You are saying that in so far as whether or not they are in the guide database just dictates whether or not I would have guide data, not whether or not the Tablo would find the stations when I do a scan. Is this correct?

There are a couple of things I could suggest. First, if your TV has a signal strength meter, does it show a low signal strength on the channels that the TV tunes but the Tablo doesn’t? Tuners vary in ability, and it’s possible that the signal could be just below the threshold of what the Tablo needs, but the TV can tune it in. (And I know you commented about the other channel coming in ‘clearer’ on the Tablo, but I’m not sure I understand that. With digital signals, the picture is either perfect, stuttering/macroblocking, or nonexistent.)

The other thing I can suggest will be harder to diagnose, and you’ll have to deal with the station engineer to resolve it. A little bit ago there was a post here from a user who lost a couple of channels after having them for a year. It reminded me of something I had happen several years ago running a Windows Media Center setup. My 1st post is here, and then a couple of posts down I made another post with some additional info I rediscovered:

To summarize, along with the video stream, the ATSC standard also specifies additional metadata that provides additional information about the channel content. This is the Program and System Information Protocol (PSIP) data. What happened to me is one of the local stations did some upgrades to their broadcast system, and in doing so they introduced a misconfiguration in their PSIP data. Not every device is susceptible to this sort of error. My (and probably everyone else’s) TVs didn’t care and could still tune the station in, but WMC wouldn’t tune it. Specifically, there was an inconsistency in the Transport Stream Identifier (TSID) between two sections of the PSIP data.

Since I was running PC based tuners with WMP, I was able to use a PC program called TSReader Lite to read the PSIP data from one of the tuners and could show the station engineer what the issue was. Unfortunately, that’s not possible with the Tablo, at least not for us regular users. Maybe Tablo support could look at it.

The OP of the linked thread hasn’t replied back, so I don’t know if that or some other PSIP data error turned out to be the problem, or if the Tablo is even susceptible to that sort of problem like WMC was.

My HDTV’s do not have a signal strength meter but the channels that the TV tunes but the Tablo doesn’t are very strong; I can pick them up on the TV with only a paper clip being used as an antenna. Again, those are 51-1 and 51-2. The Tablo just doesn’t find them when running a scan. The two channels the Tablo finds (57-1 and 57-2) that are not clear on the TV are what I would describe as “in-and-out” on the TV. They appear on the TV the way channels appear on a satellite signal during a blizzard, I assume they are weak signals. Interestingly, the Tablo picks these up when running a scan and they display fine on the Tablo. Thank you for the information.

If channel 51 is that strong, it is possible that it is overloading the Tablo tuner. How close are the stations to you and what type of antenna do you use? Is there an amplifier between the antenna and the TV (or Tablo)?

A quick test for overload would be to stick a splitter between the antenna and TV\Tablo and connect the Tablo to the splitter. That would have the effect of diminishing an overly strong signal to the Tablo to prevent overdriving its tuner.

1 Like

Of course the tablo has multiple tuners so it has an internal splitter.

If OTA broadcast towers are over 10 miles away with Line of Sight doesn’t mean that the tablo channel scan is reliable. It’s always fun to rescan, without updating, multiple times in a row. Since I only have 14 channels, including the sub-channels, it only takes around 20 seconds to perform a scan. The tablo signal strength results can vary between scans. I’ve seen results where the primary channel doesn’t even show up. The sub-channel has 1 red dot. An immediate rescan has both show up with 5 green dots. And the channel records just fine.

The stations are all about the same distance away because they put the towers on a high mountain located at the southwest end of Colorado Springs. The towers are located on Cheyenne Mountain at about 9,500 feet above sea level. ABC, CBS, NBC, PBS and Fox all work fine on any of my HDTV’s or the Tablo. I put a splitter in the line and it didn’t change anything. What do you know about the other person who replied and mentioned that the channels had to be in the Tablo Guide Database for the Tablo receiver to find them? I did open a support ticket as was suggested. I have performed a rescan multiple times over the last three days and the results have always been identical. Thank you to everyone who has offered opinions. I do seriously wonder if there exist a Guide Database and that the Tablo only picks up channels listed in said database.

The tuner the Tablo uses is a third party product and wouldn’t know anything about the guide Tablo uses (also from another party). The tuner would detect any frequencies independently of the guide. Now whether the Tablo applies the guide as some sort of template from which to choose which stations to list I don’t know. Possible for the tuner to detect stations that the Tablo declines to list because they aren’t in the guide… Beastman’s post indicates otherwise and is significant.

BTW KWHS channel 51 has a strong signal according to TVFool for anyone in any zip code area of Colorado Springs. So this is intriguing… Are there other Colorado Springs Tablo users out there who could verify KWHS reception?

Smurph’s response is also interesting regarding PSIP irregularity. I also would like to know whether the Tablo\tuner can be affected by PSIP metadata - from a Tablo rep.

The channels don’t need to be available in the guide for the scan to detect them. You can add a channel that is not in the guide and use manual recording until the guide data is updated.

Maybe you need to tvfool.com and antennaweb,org and put in your exact address and see what the results tell you. Maybe you need a power injector and not a splitter to be able to pick up 51

1 Like

That is correct. When 7.4 started broadcasting in Austin, TX on Good Friday, I simply did a scan and Tablo had it. The guide was blank because it was a new (and excellent) station…METV. So I used www.titantv.com for guide info and did manual recordings.until Tablo finally got correct Guide information. Same thing for GRIT, LAFF, COZI, ION., BUZZR. 2016 has seen all these English stations start in Austin, TX.

I had some of the channel 17 go blank but on both TV and Tablo. Hope new stations come. Since they are gone on both TV and Tablo i think they are gone.
What antenna do you have? I see it is a low power station. Tablo has an internal 4 way splitter, so you might need am amplified antenna. I have a Winegard FL5500A and it is excellent. I even get 2 stations that are in Killeen during the winter.

TVFool shows strong reception (+26 NM) for channel 51 in your area even though it is a low powered ("-LD") station. However if for some reason you would need an amplifier, I would recommend the RCA TVPRAMP1Z preamp which is quite overload resistant (since you have strong +60 NM stations). It has been tested at a variety of forums in conditions of mixed weak and strong RF signals and does not readily overload a tuner. Lowes carries them for $30 which means you could pick one up, test for your situation and see whether a preamp applies to your problem (if not return it within 30 days).

If you need a channel specific preamp (no amplification except for 51), try Jan Jenca who makes channel specific preamps. You tell him that you need a channel 51 specific preamp just to boost up that channel\frequency. I’ve used Jenca for just such circumstances.

If however it is not a signal strength issue but as Smurph indicated possibly a PSIP issue, do what a friend of mine did. He got a “channel specific” DVR just for one channel that his Tablo was having issues with - a Homeworx 180. He absolutely wanted to be able to record this specific channel and was willing to have 2 DVRs - one (Tablo) for all the channels minus one; another DVR for the Tablo problematic channel (with which the 180 seems not to have metadata issues). Several people have used the Homeworx as a backup to their Tablo including me (check the various forum threads about that). MarkKindle uses his just for recording sports events. The 180 goes for the ridiculously low price of $30 so it also could be a cost effective solution (of sorts)!

1 Like

@telemark

Definitely give our support team a shout. Via a remote session, we can manually probe the channels the Tablo isn’t picking up. From there, we should be able to figure out the root cause.

The insights from @smurph are spot on. The PSIP data is necessary (as it is set by the standard) in order for the channel (and its guide data) to populate. We’ve seen a few isolated instances (maybe… 3-4, ever) in which the broadcaster is not transmitting the PSIP data. If this is the case, the broadcaster needs to solve this on their end.

Is broadcast and display both 51? The antenna needs to be for broadcasr frequency if you get specific one.

Yes both virtual and real channel numbers are the same - 51 (KWHS). 692-698 MHz would have to be the frequency specified for a channel specific amp (i.e. from Jenca).

Question @TabloSupport - why does the Tablo need absolutely correct PSIP data when other tuners can live with PSIP irregularities? Tablo doesn’t depend on a station’s guide data as transmitted through the PSIP.