Weak Tuner lost video

[chasm_electron]

I got my TIVO series 3 in mid-October. I am experiencing similar problems to what others have experienced with a weak tuner or lost video. I am using my S3 only with standard TV, no HD yet and therefore no cable cards. The weak tuner is tuner 1 of the 0/1 pair. This tuner seems to be the frequent cause of many problems on this forum. In my case it appears the problem channels are between 32 and 49. Channels above or below this seems to be recognized by the weak tuner. BTW, all channels are acquired rapidly by tuner 0. Tuner 1 sometimes has a significant delay before it acquires the channel. On occasion, some channels in this range seem the blink in and out as the tuner loses and then reacquires the signal.

A look at the diagnostics page indicates the tuner has not acquired the signal with Not Available against Channel through to signal source and signal lock and data lock are both NO.

I tried improving the signal to the tuner by eliminating all the splitters supporting my series 2 TIVO and the TV. The splitter was a 3 to 1 splitter and induces about a 7 to 10 dB loss with a upper frequency of 2 GHZ ( not that this matters for this test). The results of this test was that both tuners behaved correctly with no non-acquired channels. Even with all the splitters in place the signal quality on the TV and S2 TIVO was excellent.

I can only surmise that the TIVO tuner 1 signal input has a marginal design and that it is very sensitive to a less than optimum signal.

Does anyone else have similar experiences? I will be calling TIVO and reporting this problem, and request they replace my unit. The other alternative is to get an amplified high grade splitter behind the TV system providing a good quality uniform signal level to all TIVOs and the TV.

Any other suggestions? It seems that TIVO must be pressured to respond to this problem.

[Austin_Martin]

There is another thread running around about this. I just got my s3 a week ago Friday. I just noticed today that one of the tuners does not tune all of the analog channels. I will be phoning TiVo next week, and see if they will acknowledge the problem. The biggest concern I have is that it was so difficult to get the cable cards set up, that I'm wary of having to reinstall in a replacement unit.

In one of the other threads on this issue, they said it might be fixed in the next s3 software release, whenever that happens..

[chasm_electron]

Since posting the problem with the weak or bad tuner (1 of the 0/1 pair), I have run some experiments. First, I have no problem at all with any other TV tuner type system, with tuning any of the analog channels 30 to 50. I have verified this on my series 2 TIVO, the 35 inch Toshiba SD TV, another Mitsubishi TV, and my Hauppauge TV tuner in my PC using SAGE TV.

The problem only shows up with the series 3 tuner #1. However occasionally, I have seen a brief problem with tuner 0, but is very short lived. Tuner 0 generally locks to any of the channels with no problems.

The problems have seen are a total inability to lock into any of the channels in the 30 to 50 band, or a partial tuner lock where the video blinks in and out of tune alternating between the grey screen and the actual program content. In the case of a total failure to lock into the channel, the TIVO displays a message saying it is searching .... The diagnostics say that the channel in Not Available along with other related data. In the case of the blinking channel tune situation the diagnostics update showing the changing time from tune to not tuned along with other valid channel data and alternating to the not tuned data.

From reading the posts on this forum there is an erroneous opinion that this is due to the Cable cards that are inserted in the TIVO. I my case I have no cable cards and am only looking at the SD analog channels. Therefore it must be related to the tuner or the cable signal quality.

Using an adjustable gain CATV amplifier, and using the Toshiba TV as a reference I changed the video levels between low signal level (lots of noise in the picture) and too high a signal with herring bone noise in the picture. While the picture quality did change on the TIVO and all my other TV signal devices it did not make any significant difference to the way my TIVO series 3 tuned into these channels. The gain swing I used ranged between 0 and 8dB with an additional 7dB loss when I inserted a signal splitter before the amplifier.

From this I hypothesize, that there is indeed a problem with the tuner in the TIVO series 3 systems in that it cannot tune into the center frequencies of affected channels, i.e, 30 to 50 or, in some cases from other people, other bands. All my other devices were able to reliably tune into any of these channels at either high or low signal levels.

I have not yet had my Charter cable man out to measure the actual signal levels for these bands or the center frequencies of these channels. This should not be necessary since other devices and other people in the local area are not having TV signal problems.

I would suggest the moderator of this forum establish a new posting asking fro information about series 3 analog tuner problems, i.e. Cable provider, affected channels, which tuner 0 or 1, and nature of problem (total loss or blinking), etc.

I will be calling TIVO tomorrow to see if they have any suggestions ???.

Charles