@tamole - In that case CBS could be at the edge of the digital cliff, and falls off in the evenings because of temperature inversions.
Have you tried running a fresh channel scan in the evening to see if CBS is continuing to receive 5 green dots?
No, but I will.
@tamole Excellent - let us know if you donât see a signal drop into orange or red territory. If thatâs the case, we can look at a few different things from our end.
We have serious issues with CBS as well as ABC. NBC and FOX mostly run better, but not well. The signal does not drop off in the evening and that is the only time we record with Tablo I sometimes watch shows in the daytime I have recorded from the previous eveningâs lineup and the reception is garbled and terribly pixelated. I understand that it has no significance when I watch them, only when I record them, but wanted to add that anyway.
Sure am tired of spending money for the annual guide because we are still unsure if we are going to get rid of it. We are moving a few blocks away and maybe that will help. I certainly hope so or Tablo is toast with us. After over 2 years this should be working far better than it is.
I donât know if it will help but it will definitely change the situation. Your issue is with the antenna and/or line from the antenna. I see above that you tried a different antenna and the situation improved / changed. That plus the fact you have tried 2 different Tablo boxes pretty much confirms this.
For starters, you can not compare the Tablo signal quality to that of the TV directly. The Tablo has a 4 way splitter inside. With HD TV (ATSC) it is a digital signal, meaning the broadcast is sending data. It doesnât take many peices of missing data and the screen is heavy pixelated or gone. The days of being able to watch a channel while fuzzy are gone, for the most part the picture is there or its not and the very little window in between (pixelated) is as little as 3db of signal.
Every time you split a signal, it drops ~3.5db, so only splitting the line into 2 could be enough to provide Tablo with a low enough signal that it wouldnât work when the TV will (and again, its actually splitting it into 4 meaning it will drop ~7db)
Finally, not every tuner is created equal, I have connected my antenna directly to my TVs and some of them get a lot more channels and better reception than Tablo, some get much worse.
Does your TV have a signal meter on it? You may can use that to see that your signal, even when connected directly to your TV, may be near cutoff.
I guess bottom line is this, it may be True that Tablo will simply not be a good solution for you, but if you are truly wanting to make it work, your focus needs to be on your antennas.
As pointed out above, your signals are not all in the same direction, you will need an antenna with a wide range. If your outside antenna is a Yagi style (looks like its an arrow pointing a certain direction) then it will be great for any broadcaster it is directly pointed at but will not get the others much (if at all). The indoor antenna you tried is indeed a multidirectional.
In my situation, I had channels in 3 distinct directions, with stations up to 47 miles away⌠Even the mutlidrectional would not work for me (while they do pull in a broader range they are still somewhat directional and with the distances I was overcoming, no single antenna was going to get them all).
So I ended up with 3 separate antennas pointing 3 separate directions and then combined into one coax. It took a lot of time and effort and I cant tell you how many times I was up there turning each antenna fractions of degrees trying to dial it in perfect, not to mention 3 different amps, various signal combiners and filters, but in the end it works.
Since you are moving to a new location you might consider hiring a company to come install the correct antenna and run new lines. Not only are you certain to have the antenna type that works for your location but they will have a signal meter and can point it perfectly.
Sorry for the long post, hopefully something in here helps some.
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Is there Tablo documentation or schematics available to customers showing that there are RF splitter(s) inside Tablos? Anyone got a photo to show us the splitter? Seeing is believing.
Theoretically an antenna signal can be split arbitrarily and entirely in the mathematical/discrete/digital domain, with zero attentuation due to splitting.
How do we know for sure whether Tablo uses an all-digital approach for splitting or uses analog/RF splitters? Or both!?
Tablo employees on this forum have confirmed the existence of the splitter. Pre-tuners. Seems like that should be documentation enough.
Iâm not an RF engineer, but AFAIK that can only be done post-tuner. Because until it goes through the tuner itâs analog RF data, not digital data. After that, yes, sending the bitstream to multiple decoders would have no loss. That should work for multiple subchannels, but not for different (RF) channels.
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And hereâs the thing. A tuner, as I understand it is the thing that singles out the ânoiseâ that constitutes a specific channel. To split post-tuner, youâd have one channel that you can split. You have to split pre-tuner if you want the full spectrum of channels available to the tuner.
I found this video once - not sure if components change over time, but at least it gives some insight into the Tabloâs innards:
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Tablo is up and running. i was giddy happy with it last night during optimal atmospheric conditions, green dots everywhere wall to wall treetop tall, 5 by 5, all the good stuff.
But sadly there is a UGE reception issue consistent with low signal level this morning and it seems worse on tablo than on hd homerun or any of the other 14 or 17 ATSC tuner/devices Iâve used since early adopting ATSC tv reception which seems to be an annoying teenager.
60% of the channels disappeared overnight and rescan wonât find them.
atmospheric conditions went from bestcase to worstcase for OTA overnight indeed. wet leaves and snow on evergreens as tall as redwood trees.
it is an expected strike 1 against the tablo. canât cancel paid service completely due to this unless i add another antennas 
argh.
For today i would to have to split again to A/B test the homerun-extend against this tablo but the result is already probably a fail and consistent with all known information. ihave no access to the attic while spousal approver is beauty-sleeping, else i would be recabling now to test in the worst-case atmospheric conditions the antenna is seeing currently.
antenna is a CM4248 attic yagi which has served well since early adopting hdtv in 2001. no preamp on the antenna in recent years although i used one in early years when xmitters were weak. also the cable run is now 6 feet compared to 100 or 150 feet in the early years.
all the channels i want are broadcast in a straight line to needham mass except for the primary local which is directly behind, i am talking 178 degrees. perfect for the tiny yagi reverse lobe on its antenna sensitive Smith Chart . also painstaking work decades ago found optimal antenna placement - pointing off-center couple degrees and positive azimuth.
i could try preamp or normal amp now but i canât find a good one that actually increases reception and hd homeboy did not seem to need it. i would disconnect tablo in a jiffy now and scan with hd homeboy but do not have access. oh well.
atsc seems to be an annoying teenager compared to the charming early adoptee it was in 2001 with much lower power xmitters. sucks that reception can still be so exquisitely bad even with the tinfoil-hat-penetrating gigawatt transmitters in use today. the tablo software seems off the charts awesome from what iâve seen, too bad a critical spousal use-case channel dropped due to freezing rain this morning. me, i would pretend not to care that i canât pick up the only legit local affiliate in my home state. Spousal approvers typically will not compartmentalize technical problems like us engineers.
see you around the grid, folks. tablo will find a way into the home mix here but geographic facts and climate sameness indicate that the reception issues will persist.
will atsc 3.0 bring better reception? probably thatâs what regular people (not engineers) care about more than whatever data/2-way services .
6â cable run? Where is your Tablo? In the attic? Whatâs the temperature where the Tablo is housed?
yes its in attic. probably about 40F up there recently on a warm day. many or all of the crucial use-case channels came back after a post-dawn rescan. hooray except the local affiliate news broadcast looks like minecraft and the audio is cutting out.
That is outside of the recommended operating temperature, maybe itâs too cold. I recommend you take it out of the attic, that could be causing your problems. See link below.
âTablo is passively cooled and is happiest at room temperature (41°F - 95°F or 5°C - 35°C for our fellow Canadians). This means that Tablo shouldnât live in garages or attics where it can get too cold or too warm, or experience major temperature swings which can create condensation inside the unit.â
https://www.tablotv.com/blog/tablo-faqs-where-should-i-place-my-tablo/
I made a big thread about this when I first got my tablo, it NEEDS a clean powerful signal. This means outdoor antenna. If you just want like 1 or 2 channels and they come in flawless with an internal antenna then fine, but if you want as many as you can get then an out door (not attic) is a requirement. My issue wasnât just corrupted video but the tablo would crash even on just a little signal loss. I mainly use my tablo for the big 3 stations and the first 2 were always strong but the 3rd and most important one always made me work for it. The external antenna pulls through most of the time but yea, you still get those days with different atmospheric conditions you canât see that will jumble up the channel.
Also your dots mean nothing. The dots are generated from sampling the signal over a very small window of time.
I am a retired electrical / computer engineer with both commercial FCC Broadcast Engineer First Class License, and have held all 5 levels of FCC Amateur Radio Licenses including Advanced and Extra classes. I taught RF engineering a few semesters.
I can assure you that the theoretical splitting of ATSC at carrier frequencies, nominally 500 MHz UHF, is utterly impossible in a consumer device like Tablo. A single channel A to D converter with appropriate sampling rate and bit depth (resolution) for merely creating the digitized samples of 1 TV channel will cost more than a Tablo, whereas a 4-way RF splitter in quantity 1000 is about a buck, maybe $1.25 apiece. This analog splitter will handle ALL channels simultaneously, versus the theoretical digital splitter which would need to be replicated for each of 4 A to D converters for the 4 channels.
Larry
tablo will surely find its way into my tv viewage and iâll probably plonk down for the lifetime requirement while singing âo canadaâ off-key while getting the words wrong.
same as 2001, no ota tuner can reliably meet the local affiliate requirements at my location with attic yagi and random weather occurring during new england patriots super-bowl and other games, the most important annual use-cases of all.
what seems utterly impossible technically usually isnât, but nice summary above of some of the tradeoffs and costs! for cpu power for the the utterly impossible splitter, please may we cease your web browserâs current surreptitious bitcoin mining and instead start it helping with splitting my wide-band UHF signal so i can watch the boston station formerly known as âfox 25â ?
More samples, more math, and Mooreâs Law to you all !
The concept of digital splitting is entirely possible, but not in a $200 product, especially given costs for gigasample flash converters needed to convert the incoming ATSC RF signals. The original claim of theoretical splitting digitally is correct, but the cost and complexity are not even remotely consistent with such a consumer product design like Tablo.
2 questions:
What is the web browser bitcoin mining reference about?
and
Have you tried a low noise pre-amp at the attic end of your coax feedline?
Both my Tablo 4 and Tablo 2 tuners benefitted modestly with adding the extra gain and lower NF.
Larry
My antenna signal is pretty reliable using just a Mohu Leaf 50. We are within about 30 miles of all the transmitters (most of them between 64 and 66 degrees), we just have one that is on a separate tower (NBC, at 84 degrees). That one looks to be the source of pretty much all âweak signalâ issues we have with the Tablo that result in it rebooting.
Is there anything a pre-amp would do to contribute to resolving this situation or is the only real next step another antenna? Most of the time the biggest issue the NBC channel causes is some pixelation that is short lasting and bearable. If a pre-amp would likely help and maybe prevent the Tablo reboots that then interrupt ALL recordings on ALL channels I will invest in one but itâs not a big enough issue to move to an attic or roof antenna because we would have to run all the cabling, etc.
hello Larry - The web browser bitcoin mining is a joke reference to a latest real hacker domain. Probably there are zero installed undesired bitcoin mining applets in the browser for all readers here.
But instead of ads running in browsers there can be bitcoin mining apps since arbitrary processing is possible via browsers, multiplied by arbitrarily many browsers accessing whatever.com . Personally iâd rather search for Mersenne primes, but actual criminals are probably more interested in bitcoin.
I have not tried pre-amp in quite a while but it was crucial when i had the 150 foot cable run. i donât have a functioning preamp currently but would like recommendations/pointers since iâll probably try one in summatimeâŚ
regarding a previous suggestion to move tablo from attic, that is unlikely to happen any time soon but i understand the rationale behind the suggestion.
olympics via tablo is awesome even at the recommended/non-max bitrate. Not sure if table can get traction with the TV viewing-community focus-group but i do love it. reception is the only issue and it seem unrelated to tablo itself. OTA DTV has always been less than 100% reliable here at 50 miles from towers in The Shire river valley⌠The tablo ipad/android/roku DVR software seems equal or better to the best DVR UIs iâve seen, such as tivo UI and xfinity x1 UI, for example. really really nice. itâs all such waaaaaay better responsiveness than the moxi UI which is amazingly s l o w .
Even if local user community remains unconvinced to use tablo instead of moxi, i bet i will help sell a few tablos to friends who live closer to The Hub of The Universe (Boston MA).
thank you,
bald /e
When I switched my OTA system to the Tablo, I installed new antennas With mixed results due to some near fringe stations along with some foliage attenuation. My attic mounted antennas benefit from the preamps I selected:
It appears that this model has been discontinued. No doubt, Channelmaster, and others have competent alternatives.
Obviously, the length of the coax Will impact the amount of benefit you achieve.
These are very low-cost devices, and well worth trying, particularly if you are using the four tuner Tablo on a long antenna feedline.
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A preamp generally helps for longer antenna feed lines, placed before one or more splitters, or in weaker reception conditions.
One caveat is that nearby strong signals can overload these preamps, making reception worse on some channels. YMMV so be prepared to do a little experimentation.