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Discussion Starter · #1 · (Edited)
I've been a satisfied Tivo customer since the days of my first Tivo, the Series 1. However, this week I've finally been worn out trying to fix the pixelation and "searching for signal" problems I've had since last winter. Hours and hours of time on the phone with Charter Spectrum, with Tivo support via phone and chat, and with Charter service people coming to my home has come to naught. The problem *may* be signal strength (65-70%), as Tivo claims. The bigger problem is that when Charter boosts the signal (with a 15dB booster) the Tivo diagnostic screen stops showing the signal strength altogether; instead it shows a hyphen, so we can't know if the signal has been boosted to a level Tivo support recommends (80-100%). In spite of this, Tivo phone support keeps saying Charter needs to boost the signal, as if they aren't hearing what I'm trying to tell them. They seem unconcerned that the Tivo diagnostic screen is no longer revealing the boosted signal strength. This seems a logical disconnect in Tivo support's thinking.

Strangely (?), when a Charter cable box is put in place of the Tivo the problems completely disappear.

Questions
  1. Should Tivo be continuing to tell me Charter needs to boost the signal strength when, with a booster attached, the Tivo diagnostic screen won't show the the new signal strength?
  2. Are there any Charter Spectrum users out there with a Tivo Bolt who are having -- or not having -- this pixelation problem?
  3. Am I correct that, given Tivo support's current position, Charter Spectrum support cannot possibly know what else is expected of them? The Tivo is, after all, a "black box" to them.
I have to say that, after what I've been through with Tivo support this week, I am relieved to have finally reached the point where I've decided to not renew my annual Tivo contract when it is due for renewal next month. I will miss the Tivo (and the recent new interface), especially compared to the Charter Spectrum DVR, but I can see no other choice.

DJ
 

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The cable box (or just the TV) may seem better because its only 1 tuner whereas the Tivo is 4 or 6 tuners.

Without being able to see how your cable is setup, how many splitters with how many outputs on them?

What is the signal strength and SNR on the channels? Boosted and unboosted.
 
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Discussion Starter · #3 ·
SNR is 25dB, though support seems more concerned about the signal strength. The unboosted signal strength ranges from 65-70%. The Tivo diagnostic screen won't show the boosted signal strength; instead it shows a hyphen.
 

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SNR 25 is considered low. Ideal is about 35. You might want to try another amplifier as the one use may be too strong.
 
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SNR is 25dB, though support seems more concerned about the signal strength. The unboosted signal strength ranges from 65-70%. The Tivo diagnostic screen won't show the boosted signal strength; instead it shows a hyphen.
Not on Charter (Comcast) and have a Roamio Pro (6 tuners), but I would agree that the SNR seems low to me as well. We have signal strength of 84% and 33dB SNR and have never had any pixilation issues with the Roamio Pro or the prior S3 OLED's or HD. I have a Bolt but no CableCARD as I'm setting it up for my son who is at college (currently with an HD).

Scott
 

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Discussion Starter · #6 · (Edited)
Per a friend's suggestion, I reattached the 15dB amplifier (an EDA 2100) on the cable and, as before, this completely killed all TV channels and gave me the "-" in the Tivo's "signal strength" reading. Then I used a series of -7dB and -3.5dB splitters to, bit by bit, attenuate the 15dB boost down to 8dB, then 4.5dB, then 1.5dB. None of this enabled the channels to work, nor the "signal strength" to show a value other than the "-". Only when I added another -3.5dB splitter -- thus completely nullifying the amplifier's 15dB boost -- did some channels start showing again, and then the signal strength was back to the 65% to 70% range.

It's as if any attempt to boost the signal beyond 70% causes the Tivo Bolt to lose its mind. I can't help thinking there's something wrong with this Tivo, but Tivo support disagrees, and I'm no cable TV expert. I understand my SNR is not helping me, but would that block my efforts to boost the signal strength?
 

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Sad story, I sympathize! Unfortunately (based on numerous posts here) situations where the cable co boxes work fine but TiVo doesn't are not uncommon. After seeing what you've already tried I have no suggestions other than swapping in a new TiVo. And that may not fix it, and I'm sure the cost and hassle to do that are significant.

I suspect your cable incoming signal strength is too low (for TiVo) and you haven't been able to boost it just the right amount (i.e., not too much). But you would either need to find just the right amplifier or get the cable co to increase their signal (not likely to happen since their equipment likes the signal).

Where did you insert the splitters? They should be inserted **ahead** of the amplifier input to prevent saturation in the amplifier. Using splitters as attenuators kind of works but there can be issues due to impedance mismatch (reflections) if the unused splitter taps don't have a matched load connected. Using inline coax attenuators is preferable and they don't cost much -- search "cable tv attenuator" on Amazon.
 

· Just the facts ma'am
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In case anyone cares the TiVo under discussion is a Bolt.
Thanks. When the OP said
It's as if any attempt to boost the signal beyond 70% causes the Tivo Bolt to lose its mind.
I thought he was talking about a Roamio OTA
 

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Per a friend's suggestion, I reattached the 15dB amplifier (an EDA 2100) on the cable and, as before, this completely killed all TV channels and gave me the "-" in the Tivo's "signal strength" reading. Then I used a series of -7dB and -3.5dB splitters to, bit by bit, attenuate the 15dB boost down to 8dB, then 4.5dB, then 1.5dB. None of this enabled the channels to work, nor the "signal strength" to show a value other than the "-". Only when I added another -3.5dB splitter -- thus completely nullifying the amplifier's 15dB boost -- did some channels start showing again, and then the signal strength was back to the 65% to 70% range.

It's as if any attempt to boost the signal beyond 70% causes the Tivo Bolt to lose its mind. I can't help thinking there's something wrong with this Tivo, but Tivo support disagrees, and I'm no cable TV expert. I understand my SNR is not helping me, but would that block my efforts to boost the signal strength?
It seems like you need to bypass the 15db amplifier for the bolt and possibly attentuate the signal down even further.
 

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It seems like you need to bypass the 15db amplifier for the bolt and possibly attentuate the signal down even further.
Don't see how that can make sense if the signal is already down to the 65 to 70 range without amplification.
 

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Don't see how that can make sense if the signal is already down to the 65 to 70 range without amplification.
Amplifying the signal makes it worse and causes the Tivo to fail to register the signal strength. Removing the amplification incrementally with attenuators improves the picture and causes the tivo to register the signal strength. It's worth a try.
 

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Discussion Starter · #14 · (Edited)
I'm still digesting the welcome additional comments that have shown up this morning. Thanks.

Using CBS HD channel 781 as my guinea pig I did another experiment this morning: I removed all splitters and amp from the cable, then put in place a splitter with -5dB attenuation (3 outputs, one of which is unused). This had the effect of getting me the normal, pixelated image on channel 781, and a signal strength (according to the Tivo diagnostics screen) of 67%. I then took that splitter off and replaced it with a -3.5dB splitter (two outputs). This caused the "searching for a signal on this channel...v52" to show up on channel 781, and a "-" in the Tivo signal strength field. That seems just the opposite of what should have happened? Damned peculiar, as James T. Kirk once said.
 

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Discussion Starter · #16 ·
Sad story, I sympathize! Unfortunately (based on numerous posts here) situations where the cable co boxes work fine but TiVo doesn't are not uncommon. After seeing what you've already tried I have no suggestions other than swapping in a new TiVo. And that may not fix it, and I'm sure the cost and hassle to do that are significant.

I suspect your cable incoming signal strength is too low (for TiVo) and you haven't been able to boost it just the right amount (i.e., not too much). But you would either need to find just the right amplifier or get the cable co to increase their signal (not likely to happen since their equipment likes the signal).

Where did you insert the splitters? They should be inserted **ahead** of the amplifier input to prevent saturation in the amplifier. Using splitters as attenuators kind of works but there can be issues due to impedance mismatch (reflections) if the unused splitter taps don't have a matched load connected. Using inline coax attenuators is preferable and they don't cost much -- search "cable tv attenuator" on Amazon.
Yep, swapping in a different Tivo Bolt is what I would like to try, but for the expense of buying one at the risk it wouldn't help. One thing I think I might do is take the Tivo and tuning adapter to my parents'. They have Charter Spectrum, too, and if I get a cleaner signal that is in the 80-100% zone then maybe there's a Charter problem at my home, after all.

Boost it the right amount? So it may be that I need to buy a combination of attenuators that allows me to reduce the booster's 15dB, 1dB at a time. I can certainly try that.

Splitters *ahead* of the amp? Oh crud, I did just the opposite. I may have misunderstood a post I read elsewhere to put the splitters *behind* the amp. I'll rerun last night's step-by-step attenuation experiment, this time with the booster as the *last* item on the cable before it attaches to the Tivo. I'll have to have at least one splitter *after* the amp, though, since I have to feed the signal into both the Tivo and the tuning adapter. I understand I will ultimately have to buy some proper attenuators . thanks for the addition ideas to try out.

I
 

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Discussion Starter · #17 · (Edited)
Amplifying the signal makes it worse and causes the Tivo to fail to register the signal strength. Removing the amplification incrementally with attenuators improves the picture and causes the tivo to register the signal strength. It's worth a try.
Actually, removing the 15dB amplification incrementally with (splitter) attenuation doesn't help at all until I get back to where (1) the amp boost is completely nullified, or (2) there's just a -5dB splitter on the line and *no* amplifier. Wierd. The idea to *further* reduce the attenuation, incrementally, is a good idea I'll try. Yeah, it seems illogical but this doesn't seem to be a logical set of results I've been getting. Thanks.
 

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Discussion Starter · #18 ·
Just throwing this out there... every I've experienced picture or signal problems; it's been due to a damaged (read rodent chewed) coax cable at the utility pole.
Good suggestion. However, when all his other efforts failed the Charter service guy that worked the problem this week at my home replaced everything from the power pole clear up to my Tivo -- completely new coax. Maybe if I get different signal strength/quality results when I try my Tivo at my parents' (they have Charter Spectrum, too) then I can pressure Charter to take a closer look at other hardware on the power pole or at the Charter substation that feeds into my street.
 

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Discussion Starter · #19 ·
The cable box (or just the TV) may seem better because its only 1 tuner whereas the Tivo is 4 or 6 tuners.

Without being able to see how your cable is setup, how many splitters with how many outputs on them?

What is the signal strength and SNR on the channels? Boosted and unboosted.
That makes sense; Charter's box is only two tuners, as I understand.
 

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Discussion Starter · #20 ·
It seems like you need to bypass the 15db amplifier for the bolt and possibly attentuate the signal down even further.
That's sure what it seems like. See my post where, if the only splitter on the line is -3.5dB then it goes to "searching for signal" message, but a -5dB splitter improves things to where I have an image, albeit pixelated.
 
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