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Old 08-23-2007, 07:45 PM   #181
mjsmith3
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Compulady,

I had what might be the same issue as you. Tivo S3 was fine. TivoHD was ok on card 1 but horrible pixellation on card 2. Mostly fixed by forcing several calls and rebooting. Now I only have the minor pixellation issues that many people with SA cards have.
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Old 08-24-2007, 12:15 AM   #182
johnnylundy
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Have we in fact determined that Motorola M-Cards do not have the problem?

Does everyone who has the pixelation have it on both tuners?
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Old 08-24-2007, 04:31 AM   #183
jfh3
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Quote:
Originally Posted by johnnylundy
Have we in fact determined that Motorola M-Cards do not have the problem?

Does everyone who has the pixelation have it on both tuners?
Not sure there's enough data to say that no one with a Motorola MCard sees the problem, but I have an Moto MCard on two boxes - saw pixelization before b2, but not after.
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Old 08-24-2007, 07:46 AM   #184
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Great news. I'm getting a TiVo HD before the TV season starts, and hoping to try for an MCard. Ditching the useless Moto 3416.
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Old 08-24-2007, 05:09 PM   #185
mchief
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I have only one channel that is horrible - almost unwatchable. I have a SA cable card in the HDTV and PIP. Side by side the TivoHd is horrible - the SA cable card in the TV has no problem. An hour later the picture was fine on THD. This is the HD version of Golf Channel. I had problems with the SA8300HD - some macro blocking on most channels, but only occasionally. Some day all channels on the 8300 were unwatchable.

I have a SA M-Card from Comcast, Alexandria, VA and 1b

I have had the THD for only 1 week and other than the GC have seen very infrequent problems. Once in 2 or 3 hours.

Last night I saw a >1 second burst on a recorded SD program, but no more.

I cannot explain the GC problem, on the 8300 this was frequent which I attributed to the channel because it would usually go off the air after significant macro-blocking problems.
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Old 08-24-2007, 06:59 PM   #186
Dr_Diablo
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The pixelation has gotten worse since the latest "patch"... now the screen freezes on a few of the HD channels/feeds
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Old 08-26-2007, 02:21 AM   #187
navman
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Thought I would chip in.

Got my TivoHD a few days ago and had the cable cards installed, without a glitch even though the installer just brought 2(S-cards). Have had a lot of macroblocking/pixellation issues about 1 a minute but that hasnt been my main issue. It has been the audio dropouts, saw "The Hills Have Eyes" recorded from HBOHD which consistently has a signal strength of over 90. Probably had the dropout happen every 5 minutes or so, very irritating. I know that is something I will not be able to live with. The much maligned SA 8300HD which I had for over a year never had any of the two above mentioned issues.(even though my signal strength was much lower when it was connected to the SA box, took care of that issue when I had the cablecards on the TivoHD installed) On the bright side love the tivo interface when compared to the SA box, always have and thats why I upgraded from Series2. Unfortunately if there is not a fix to these issues I see myself having to go back to the SA8300HD as much as I would hate too. I bought the TivoHD not because I wanted a compromise but because I wanted the BEST, and so far it leaves a lot to be desired...........
Both the pixellation and audio dropouts are reproducible on rewinding. When I first read about the pixellation issues, I thought it was people complaining that had nothing better to do(and were absolute sticklers for perfection) , but as you can see from the length of my post it is really very irritating and makes some recordings unwatchable, and thus my rant.

Last edited by navman : 08-26-2007 at 02:37 AM.
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Old 08-26-2007, 06:48 AM   #188
johnnylundy
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Are these SA cards, or Motorola?
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Old 08-26-2007, 10:31 AM   #189
navman
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hmmm thought i mentioned it, but i guess i forgot to, they are SA cards.
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Old 08-26-2007, 04:23 PM   #190
dtivofan23
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Navman I Am Having The Same Issues I Hope Tivo Fixes This Because I Really Dont Wanna Have To Return This Box.

I Also Was Using A Sa8300hd And Didnt Have These Issues But The Sa Interface Is Garbage. Hopefully This Issue Has Nothing To Do With The 2 Sa Cards That I Using Now.
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Old 08-26-2007, 05:56 PM   #191
johnnylundy
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It's looking more and more as if most of the folks having the problem have the SA cards.

When I call for my install I am going to see first if I can do a self-install with an Mcard, and if not, at least if the installer can bring a Moto Mcard. It's worth a try.
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Old 08-26-2007, 06:06 PM   #192
TokyoShoe
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Quote:
Originally Posted by johnnylundy
It's looking more and more as if most of the folks having the problem have the SA cards.

When I call for my install I am going to see first if I can do a self-install with an Mcard, and if not, at least if the installer can bring a Moto Mcard. It's worth a try.
Actually I have the problem big time on all HD recordings, and I am using Motorola Cards.
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Old 08-26-2007, 09:49 PM   #193
wbradney
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Same here - Motorola (S) cards in my Series 3 on Verizon FIOS.
But in my case I've only started seeing severe macroblocking in the last two weeks or so. I had similar problems back in Jan-Feb, but an update in late Feb seemed to fix the problem and I haven't seen any significant problems until early Aug.

This morning most channels (SD or HD) were barely watchable (constant pixellation/audio drops) on the S3 (both tuners), but all were fine on my S2 via the Verizon/Motorola SD STB, so I decided to try to do as much troubleshooting as possible before calling Verizon.

My default setup is as the Verizon techs left it -- line into a 6-way -12db splitter, 1 out to the TV room, where a 2-way -3.5db splitter drives the S3 and the SD STB, 1 out to the Verizon/Actiontech router, 4 others terminated.

I noted the signal strength reported by the S3 on all channels - the average range was 80-90, but severe macroblocking occurred on probably 75% of the channels, and for those channels the signal would jump all over the place, sometimes even dropping to zero/grey screen, or reporting "No signal on tuner 2".

Next I took the SD STB and the splitters out of the equation and wired the Verizon line directly into the S3 (I was a little wary of this since the FIOS signal is supposed to be so 'hot' -- but I was pissed off at having such a crappy signal). This improved things somewhat.

The signal strength meter now showed consistently 95-100 for almost all channels and no pixellation on those channels where the meter stayed solidly inside that range. As I went through all of the channels, however, some 20 or so still showed severe macroblocking after 2 or 3 seconds of being tuned (curiously, the first few seconds even on those channels were good, then it deteriorated to being unwatchable/grey screen after about 10 seconds).

Those bad channels were (on the Verizon/Freehold system):

67 SNY
102 SCIENCE
103 DISCTIMES
105 MILI
141 DHC
143 FITTV
144 FOOD
145 HGTV
148 DCHOME
169 BBCA
170 COMEDY
177 FOXREAL
178 FUEL
229 DCKIDS
408 HBOC
410 HBOZ
830 YESHDNY
851 HBOHD

Only a couple of these I care about, so I decided to put the 2-way spiltter back in place to bring the SD STB back into the mix, and the levels stayed pretty much the same, with same unwatchable channels. Only a couple of those channels I really care about, one of which is also available SD, so I declared a temporary victory and left the 6-way splitter and the ActionTech out of the loop.

A couple of hours later I noticed the general, widespread macroblocking was back, and now most channels were again crappy, although it seems not quite as crappy as at the start of the day (1-2 second drops every 20-30 seconds, so still unwatchable).

I put everything back the way it was to begin with, and now perversely only those channels above are bad again -- I'm getting 90 or above for most channels and they're rock-solid, but those same channels above are lousy.

Next step I guess is to call Verizon and have them come and tell me it's Tivo's problem...

I should reiterate that between the end of Feb and the beginning of Aug I noticed no appreciable pixellation at all.

Also, the pixellation occurs in recordings, and when rewinding the live buffer.
Never seen any problem with the Menus.

Last edited by wbradney : 08-26-2007 at 09:54 PM.
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Old 08-27-2007, 03:45 PM   #194
fullmetaljester
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I had the base firmware out the box, had horrible pixel issues. However the latest update fixed it completely, been using it all weekend no problems. The lag between channels is annoying but not a showstopper. I do realize its more the tuning of the CC than the Tivo.
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Old 08-29-2007, 11:36 AM   #195
compulady
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How do you get this firmware? I am getting alot of pixelation.

Quote:
Originally Posted by fullmetaljester
I had the base firmware out the box, had horrible pixel issues. However the latest update fixed it completely, been using it all weekend no problems. The lag between channels is annoying but not a showstopper. I do realize its more the tuning of the CC than the Tivo.

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Old 08-29-2007, 01:46 PM   #196
richsadams
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Quote:
Originally Posted by wbradney
Same here - Motorola (S) cards in my Series 3 on Verizon FIOS.
But in my case I've only started seeing severe macroblocking in the last two weeks or so. I had similar problems back in Jan-Feb, but an update in late Feb seemed to fix the problem and I haven't seen any significant problems until early Aug.

This morning most channels (SD or HD) were barely watchable (constant pixellation/audio drops) on the S3 (both tuners), but all were fine on my S2 via the Verizon/Motorola SD STB, so I decided to try to do as much troubleshooting as possible before calling Verizon.

My default setup is as the Verizon techs left it -- line into a 6-way -12db splitter, 1 out to the TV room, where a 2-way -3.5db splitter drives the S3 and the SD STB, 1 out to the Verizon/Actiontech router, 4 others terminated.

I noted the signal strength reported by the S3 on all channels - the average range was 80-90, but severe macroblocking occurred on probably 75% of the channels, and for those channels the signal would jump all over the place, sometimes even dropping to zero/grey screen, or reporting "No signal on tuner 2".

Next I took the SD STB and the splitters out of the equation and wired the Verizon line directly into the S3 (I was a little wary of this since the FIOS signal is supposed to be so 'hot' -- but I was pissed off at having such a crappy signal). This improved things somewhat.

The signal strength meter now showed consistently 95-100 for almost all channels and no pixellation on those channels where the meter stayed solidly inside that range. As I went through all of the channels, however, some 20 or so still showed severe macroblocking after 2 or 3 seconds of being tuned (curiously, the first few seconds even on those channels were good, then it deteriorated to being unwatchable/grey screen after about 10 seconds).

Those bad channels were (on the Verizon/Freehold system):

67 SNY
102 SCIENCE
103 DISCTIMES
105 MILI
141 DHC
143 FITTV
144 FOOD
145 HGTV
148 DCHOME
169 BBCA
170 COMEDY
177 FOXREAL
178 FUEL
229 DCKIDS
408 HBOC
410 HBOZ
830 YESHDNY
851 HBOHD

Only a couple of these I care about, so I decided to put the 2-way spiltter back in place to bring the SD STB back into the mix, and the levels stayed pretty much the same, with same unwatchable channels. Only a couple of those channels I really care about, one of which is also available SD, so I declared a temporary victory and left the 6-way splitter and the ActionTech out of the loop.

A couple of hours later I noticed the general, widespread macroblocking was back, and now most channels were again crappy, although it seems not quite as crappy as at the start of the day (1-2 second drops every 20-30 seconds, so still unwatchable).

I put everything back the way it was to begin with, and now perversely only those channels above are bad again -- I'm getting 90 or above for most channels and they're rock-solid, but those same channels above are lousy.

Next step I guess is to call Verizon and have them come and tell me it's Tivo's problem...

I should reiterate that between the end of Feb and the beginning of Aug I noticed no appreciable pixellation at all.

Also, the pixellation occurs in recordings, and when rewinding the live buffer.
Never seen any problem with the Menus.
Since you have an original S3 and this thread is "Tivo HD Pixelation Troubleshooting" for the new TiVo HD units, you may want to check a couple of other threads that focus on the original S3 including:

S3 Pixelization /Macroblocking?

Based on everything you've said it sounds very much like you have a signal problem. The S3's processing ability is very sensitive to signal degradation of any nature. Splitters, coax cables and a number of other things can contribute to audio/video problems including macroblocking or loss of picture and sound all together. That's not to mention a new signal issue with your provider which will exacerbate things if what you had was borderline in the beginning. Best bet is to have Verizon come out and test everything, both inside and out. It may be a problem with their system, your cables/connections or your cable cards (which they can "re-hit").

FYI - TiVo's "Signal Strength" meter measures signal to noise ratios. A high reading may indicate lack of noise, but not necessarily a good signal…that can only be measured with the (fairly expensive) equipment used by the cableco’s.

Last edited by richsadams : 08-29-2007 at 01:55 PM.
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Old 08-29-2007, 01:52 PM   #197
richsadams
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Quote:
Originally Posted by compulady
How do you get this firmware? I am getting alot of pixelation.
Firmware is downloaded and installed automatically...no action is required on your part.

It's likely that you already have the latest firmware for the TiVo HD which is v8.1.7b and for the original TiVo S3, v8.3.1 (which has been out for a while now). You can check this by going to TiVo Central (the TiVo button on your remote control) > Messages & Settings > Account & System Information > System Information and looking at the Software Version line.
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Old 08-29-2007, 04:03 PM   #198
mchief
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I was watching the almost unwatchable UHD US Open Tennis coverage. Macroblocking is terrible. I have an SA M-Card in my THD. I also have a SA S-card in my TV. Using PIP I put the tivo picture split screen with the tv/cc. No macroblocking to speak of on the tv while significant distortion on the tivo. There is also a 2 second delay on the tivo when compared to the tv. Not sure what that means other than tivo may be on it's way back to CC.
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Old 08-29-2007, 08:05 PM   #199
mjsmith3
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Still getting horrible/frequent pixellation on many channels. 2 SA cards. Tivo seemed to fix the Motorola card issue pretty quickly. I'm a little disappointed in that is has been a few weeks since then and this issue is still unresolved for me with my SA cards.
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Old 08-29-2007, 09:59 PM   #200
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Quote:
Originally Posted by richsadams
FYI - TiVo's "Signal Strength" meter measures signal to noise ratios. A high reading may indicate lack of noise, but not necessarily a good signal…that can only be measured with the (fairly expensive) equipment used by the cableco’s.
My Motorola cable modem (retail cost under $100) can display both a "downstream power level" reading in dBmV and also a "signal to noise ratio" in dB.

Please enlighten me on how the sub $100 Motorola product can incorporate "fairly expensive" equipment while a $300 TiVo HD can't.

The Motorola "power level" aka "signal strength" (NOT S/N) is also quite accurate. When I inserted a 2:1 splitter the reading went down by about 3.5 dBmV. When I inserted a 6 dB attenuator the reading went down by about the proper amount. When I inserted a 15 dB distribution amplifier the reading went up by the proper amount.

It isn't rocket science, and it isn't as "fairly expensive" as you say.
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Old 08-29-2007, 10:04 PM   #201
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Tivo HD software update.

Talked to tivo customer service about pixellation issues on my tivo hd. was told they released a new software a few days ago that should fix the issue for people with SA cards. On asking them as to why I hadnt gotten this software update despite forcing several connections, i was told something to the effect of "it is a rolling release" being tested on limited tivohds and everyone should get it soon. Was I being lied to or is this the truth. The new software according to them was 8.3, which I thought was for TivoHD's older sibling. By the way I talked to Cal, he is a supervisor.
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Old 08-30-2007, 01:52 AM   #202
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Enlightenment

Quote:
Originally Posted by Phantom Gremlin
My Motorola cable modem (retail cost under $100) can display both a "downstream power level" reading in dBmV and also a "signal to noise ratio" in dB.

Please enlighten me on how the sub $100 Motorola product can incorporate "fairly expensive" equipment while a $300 TiVo HD can't.
Well, for several reasons, actually. First of all, there is a difference between "can't" and "doesn't". The modem does, the TiVo doesn't. The fact the TiVo designers decided not to incorporate a more fully featured signal measurement system has nothing to do with the fact the modem designers decided in favor of the measurement utility. We could have noses as sensitive as a dog's, but we don't. Willie Shoemaker could have been as big as Ed "Too Tall" Jones, but he wasn't.

Secondly, Your coffee pot could have a digital temperature readout, and it would not make it cost terribly much more, but it would cost a little bit more and consequently few, if any, coffee pots have built-in digital thermometers. Even though the cost would not be much higher it would be somewhat higher and the extra feature would perhaps be of questionable value in most consumer's minds. Was it a bad decision on the part of the TiVo engineers not to incorporate a more significant signal measurement system? 'Not really. Incorporating it might have been a slightly better decision, but then they would have had to use a different receiver than they did, which could have spelled other troubles of which we are not aware. It's unlikely TiVo makes the receiver. It's almost surely an OEM part delivered to TiVo's assembly plant by the manufacturer. It's possible it was custom engineered to TiVo's specs, but more likely TiVo simply purchased an off-the-shelf module.

Thirdly, while a poor enough signal level will definitely cause problems for a digital receiver like the TiVo, it is only one of a large number of likely culprits to cause problems on a CATV system, and probably not the most likely, at that, especially for a digital signal.

Quote:
Originally Posted by Phantom Gremlin
The Motorola "power level" aka "signal strength" (NOT S/N) is also quite accurate. When I inserted a 2:1 splitter the reading went down by about 3.5 dBmV.
No, it went down by 3.5dB, not 3.5dBmV. A Decibel (dB) is a way to compare two signal levels. A dBmV is a specific amount of power. One dBmV is an amount of power equal to .0168 microwatts. A change of 3.5dBmV is a reduction (or increase) of .0298 microwatts, no matter what the original level may have been. A change of -3.5dB is a halving of the original signal, whether it was originally 20dBmV, 0dBmV, or -50dBmV. Inserting a 2-way splitter into an RF line will cause the signal level to drop by .0298 microwatts (+3.5dBmV) if and only if the signal level without the splitter is .0597 microwatts, or +7.0 dBmV. In other words, adding a splitter will change the signal level by -3.5dB, not 3.5dBmV, except in the unique case where the original signal level is +7.0dBmV.

If the unsplit signal level were +60dBmV, adding the splitter drops the signal level by -3.5dB, or in that case by 5.96 milliwatts, which is a drop of +56.5dBmV. If the unsplit signal level were 0dBmV, adding the splitter will again change the level by -3.5dB from 0 to -3.5dBmV, which is a change of -3.5dBmV.

Well isn't that the same as the change from +7dBmV to +3.5dBmV? No the change from +7dBmV to +3.5dBmV is +3.5dBmV, or .0298 microwatts, while the change from 0dBmV to -3.5dBmV is -3.5dBmV or 6.7nanowatts - 1/4 as much.

The change from +3.5dBmV to 0dBmV is 0dBmV. The change from +20 dBmV to +16.5dBmV is +16.5dBmV. The change from +55.5dBmV to +53dBmV is +53dBmV.

See the pattern?

A -1dB change frrom +60dbMv to +59dBmV is a change of +53.13dBmV. A +1dB change from +60dBmV to +61dBmV is a change of 54.13dBmV.

Last edited by lrhorer : 08-30-2007 at 03:25 AM.
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Old 08-30-2007, 01:58 AM   #203
richsadams
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[quote=Phantom Gremlin]My Motorola cable modem (retail cost under $100) can display both a "downstream power level" reading in dBmV and also a "signal to noise ratio" in dB.

Please enlighten me on how the sub $100 Motorola product can incorporate "fairly expensive" equipment while a $300 TiVo HD can't.

Quote:
Originally Posted by Phantom Gremlin
The Motorola "power level" aka "signal strength" (NOT S/N) is also quite accurate. When I inserted a 2:1 splitter the reading went down by about 3.5 dBmV. When I inserted a 6 dB attenuator the reading went down by about the proper amount. When I inserted a 15 dB distribution amplifier the reading went up by the proper amount.

It isn't rocket science, and it isn't as "fairly expensive" as you say.
Hi neighbor! Thanks for adding your thoughts. I have the same little Moto cable modem; it’s a fine piece of equipment.

With regard to the cost of professional test equipment, a very basic combination scanning signal level meter & leakage detector such as the Sadelco DisplayMax 800CLI retails for $1495.00 without any accessories. Even the MiniMax 800 retails for over $1,000.00 and decent hobbyist models run about $500.00. Of course bench equipment is much more expensive. You could check with the Comcast office up the street to see what type of gear they use and how much it costs...but I suspect it's a little more than $100.00…or maybe not.

With regard to how TiVo product development decisions are made, you'd have to ask them...I’d wager it has something to do with profit margins however.

I took a moment to offer some friendly advice by suggesting that the OP contact Verizon to have them test their service. Based on a number of your other posts it sounds like you’re pretty frustrated with the TiVo HD, and perhaps TiVo itself…understandable. But if you can, perhaps you’d care to share your thoughts on what other things the OP might do to make things better as well?
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Old 08-30-2007, 03:14 AM   #204
lrhorer
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Signal level vs S/N

Quote:
Originally Posted by richsadams
FYI - TiVo's "Signal Strength" meter measures signal to noise ratios. A high reading may indicate lack of noise, but not necessarily a good signal…that can only be measured with the (fairly expensive) equipment used by the cableco’s.
'Not true. The only significant measurement of the quality of a signal is the S/N ratio at the receiver's demodulator. Note several things, however:

1. The actual noise level includes any deviation from the precise hypothetical waveform produced by the transmitter. There may be a significant difference between this value and the value measured by the device in the receiver. How significant depends on the method used to quantify the measurement and what the actual sources of the noise are. These include noise in the original signal, amplifier noise, thermal noise, distortion components, common mode interference, superhetrodyne noise (generated by the receiver itself), and ingress carriers, among other things.

2. While it is possible to have a good signal level and still have a poor S/.N, the reverse is not true. One cannot have a good S/N with a problematical signal level. A good S/N doesn't necessarily mean the signal isn't lower or higher than it should be, it just means the difference isn't going to cause trouble, and bringing the signal level closer to optimum values isn't going to help the picture any. Doing so will only have a small effect on the S/N, and above the S/N threshold, increasing the S/N has no noticeable overall effect

3. In an otherwise perfectly functioning CATV plant, there is a direct relationship between the signal level and the S/N. If the originating signal is effectively perfect and there are no other significant sources of noise (including the receiver itself), then the S/N will increase exactly 1 dB for each dB the signal level is raised at the head-end until 3rd order distortion becomes significant. At that point, increasing the signal by 1 dB will REDUCE the S/N by 2 dB. Similarly, in a hypothetically noise free CATV plant, the only noise is going to be in the receiver itself and raising the signal level 1 dB will raise the S/N 1 dB until the signal reaches the point where thermal and superhetrodyne noise in the receiver are lower than common mode interference, at which point increasing the signal level 1 dB will REDUCE the S/N by 2 dB.

4. Unlike analog signals, whose perceived quality degrades slowly as the S/N drops, digital signals are either good or bad. The degradation window where the signal goes from being perfect over very long timescales to being completely unrecoverable is quite narrow, sometimes as little as 6dB. It's also quite low compared to analog signals. In order to produce a picture deemed identical to an original "perfect" video when viewed side by side, the S/N ratio needs to be 65dB or higher, yet the video is poor but recognizable even at 20dB. A simple PCM signal can hypothetically be recovered as long as it's S/N is greater than 6dB. In practice, however, even with the best equipment the stream will start to suffer drop-outs any time the S/N drops below about 12dB. HD Video, however, is not PCM. It's QAM. Quadriture modulation significantly increases the bit rate for a given signal bandwidth, but the cost is the S/N must be mich higher in order to prevent lost data. What's worse, the HD stream is highly compressed, so while the loss of a single bit in an uncompressed digital video stream isn't even noticeable, the loss of a single bit in an MPEG stream will likely cause a very noticeable artifact indeed. Even so, QAM receivers can be designed which operate extremely well at S/N ratios of 25 or even 20dB. I'me sure the TiVo receivers are not that good, but I would be very surprised if they required more than 30dB or at most 35dB S/N. Anything above that is just fine, and increasing it won't have any real effect.

5. Measuring the signal level is not difficult or consequently expensive. All it requires is a tuner and a voltmeter. Since the TiVo already has a tuner, all that would be necessary is to place a voltmeter circuit at the point where the signal leaves the I.F. section before it enters the demodulator. The S/N is a much more difficult parameter to measure accurately, but it can be made less so by making certain assumptions aboout the signal - at the cost of making the measurement more likley to suffer aliasing. That's in large measure where the caveat comes in about the reported S/N being good enough when in fact it is not. If this is the case, and it is due to out of range signal levels, then moving the signal lavels back toward optimum values will indeed resolve quality issues even though the measured S/N may change relatively little.
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Old 08-30-2007, 05:29 AM   #205
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Quote:
Originally Posted by navman
Talked to tivo customer service about pixellation issues on my tivo hd. was told they released a new software a few days ago that should fix the issue for people with SA cards. On asking them as to why I hadnt gotten this software update despite forcing several connections, i was told something to the effect of "it is a rolling release" being tested on limited tivohds and everyone should get it soon. Was I being lied to or is this the truth. The new software according to them was 8.3, which I thought was for TivoHD's older sibling. By the way I talked to Cal, he is a supervisor.

That "fix"...b2 was released on the 16th, an failed to solve the problem for those with SA cards, some however with the Motorola cards claim some improvement
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Old 08-30-2007, 06:37 AM   #206
mike_camden
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Quote:
Originally Posted by Dr_Diablo
some however with the Motorola cards claim some improvement
That's not accurate -- every post on this board that I have seen (with the exception of two) using Motorola cards with the Tivo HD report COMPLETE improvement. In my case pixelation is gone, and I'm very happy with Tivo. For thiose with SA cards, I'm confident that Tivo will be taking care of you based on how well and quickly they fixed the issue for us with Moto cards.
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Old 08-30-2007, 07:45 AM   #207
ChrisPA
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Quote:
Originally Posted by mike_camden
That's not accurate -- every post on this board that I have seen (with the exception of two) using Motorola cards with the Tivo HD report COMPLETE improvement. In my case pixelation is gone, and I'm very happy with Tivo. For thiose with SA cards, I'm confident that Tivo will be taking care of you based on how well and quickly they fixed the issue for us with Moto cards.
To provide a data point, I am still experiencing pixelation problems with my FIOS Motorola CC setup. This is in direct comparison to my Verizon DVR, which I have not seen experience a problem (admittedly I watch on this setup somewhat less often, so it could be that I've missed an occasional problem. With the Tivo, I can almost always flip through the channels at any time to find a channel experiencing pixelation). BTW, my signal strength is virtually always 100% with SNR of 37/38 dB

Additionally, as I think I mentioned earlier, in the few days prior to switching over to FIOS from Comcast, the Tivo also experienced pixelation problem tuning unencrypted QAM on Comcast's feed (no cable cards).

Overall things are better with B2 software, but still not perfect. It seems that fewer stations are affected, and the average severity is lessened. But... there are still occasions where a given channels is unwatchable (which channel is not consistentl).
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Old 08-30-2007, 09:08 AM   #208
richsadams
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Quote:
Originally Posted by lrhorer
2. While it is possible to have a good signal level and still have a poor S/.N, the reverse is not true. One cannot have a good S/N with a problematical signal level. A good S/N doesn't necessarily mean the signal isn't lower or higher than it should be, it just means the difference isn't going to cause trouble, and bringing the signal level closer to optimum values isn't going to help the picture any. Doing so will only have a small effect on the S/N, and above the S/N threshold, increasing the S/N has no noticeable overall effect
Ah...I stand corrected! Thanks for the clarification...I either got it wrong from my source, or they have it wrong, which isn't likely. And thanks for the additional detailed info...very good stuff.

Bringing understanding and solid information to this forum takes a lot of effort and caring; a very positive and appreciated quality.
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Old 08-30-2007, 01:39 PM   #209
Phantom Gremlin
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Location: Tualatin, Oregon
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Quote:
Originally Posted by lrhorer
The fact the TiVo designers decided not to incorporate a more fully featured signal measurement system has nothing to do with the fact the modem designers decided in favor of the measurement utility.
I respect your arguments for the TiVo not having a more featured measurement system. But I think the extra info could have been very useful.

Quote:
No, it went down by 3.5dB, not 3.5dBmV.
I understand the difference between dB and dBmV.

Quote:
See the pattern?
I need you to re-read what I originally wrote. I wrote that with a splitter inserted the reading went down by 3.5 dBmV.

Prior to the splitter the power level meter was reading -6.0 dBmV. After the splitter the power level meter was reading -9.5 dBmV. BTW, though completely irrelevant, right now my power level is reading 5.8 dBmV, with a 35.6 dB S/N. That's with a distribution amp.

The use of the word reading isn't my choice. It's in the message from the cable modem. The text is:

Power Level
5.8 dBmV
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading.


You were so anxious to exhibit your superior knowledge that you created a straw man to knock down.
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Old 08-30-2007, 01:43 PM   #210
Phantom Gremlin
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Location: Tualatin, Oregon
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Quote:
Originally Posted by richsadams
I took a moment to offer some friendly advice by suggesting that the OP contact Verizon to have them test their service. Based on a number of your other posts it sounds like you’re pretty frustrated with the TiVo HD, and perhaps TiVo itself…understandable. But if you can, perhaps you’d care to share your thoughts on what other things the OP might do to make things better as well?
Yes I'm frustrated. Mostly because the product has so much potential. It's so close to what I want, and yet not quite there. Still, I'm keeping it.

As to what the OP might do, I agree that your advice was much better than my bickering.
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