Series3 digital cable/antenna only?

worachj said:

If you run guided setup on the 648 for Cable or OTA&Cable, you will need two cable cards for two tuner capabilities.

The 648 takes two cable cards, and will revert to single tuner mode if you only have one cable card, even for the OTA tuners. With two cable cards you can record/use any combination of two OTA/Cable tuners.

Running guided setup for OTA only will have two tuner capabilities.

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Bingo - thank you. now it's coming back to me that there was something odd/unexpected/unique on the setup for S3. I set it up initially selecting ota&cable with just an antenna connected to the coax rf input, no coax cable connected to the cable rf input, and no cable card inserted and wasn't seeing dual tuner except in the dvr diagnostics where two ota channels were reported tuned in. which left me wondering - why can I only watch one - can't record both?

then i put in a single cable card (which hasn't been activated with comcast) and got the spinning wheel of please wait...acquiring channel information. that didn't go away and didn't seem you can bypass it. then I connected the cable to the rf input - still stays at spinning wheel, doesn't acquire channel info, and doesn't seem a way around it to watch live tv off the antenna.

So I suppose even if I repeat guided setup with both cards inserted and choosing cable & ota, that the spinning wheel will hang me up unless I actually activate the two cards for them to be able to acquire just the channel info, which I believe is the channel frequency map if I remember right. and I don't think there are any clear qam available anyway. And comcast is in the process of transition mpeg 4 channels anyway which the S3 won't handle. But I did want to be able to record the same program OTA & from cable (mpeg2) to compare how much compression / bitrate loss the cable file gets. but oh well, guess I'll rerun GS as ota only to get the 2 tuners and let the other tivos on the network can handle the cable channels, unless there is a workaround?? thanks.

worachj said:

If the 648 has a TiVo service subscription you should be able to run setup and get channel information with or without cable cards.

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It's PLS, same MAK as my other tivos which can see the s3 and the npl over the network, and connecting to tivo for guide data just fine - program info to July 26, and it's pulling both the cable and ota channel guide data just fine and I can see both sets in the program guide.

And in system info it shows:
Program Source (1) Digital Cable
Source Input (1) Coax Cable In
Program Source (2) Antenna
Source Input (2) Coax Antenna In

So the spinning wheel eventually timed out and went to another screen:
Error Acquiring Channels
The DVR is unable to acquire channel information from the CableCard. You can still watch live TV from the antenna and basic cable by removing the CableCard(s). You can also watch recorded programs by going to Tivo Central.

So I removed the two cable cards and voila both tuners were working and tuned into different ota channels. So I set up recordings on both tuners and that worked fine too. And the cable guide data continues to show.

Did a reboot to see if it would and it did although I got the envelope indicating new message. and it was a nag message saying to repeat guided setup - settings had changed. which removal of the cards must have generated. Checked system information again and still:

Program Source (1) Digital Cable
Source Input (1) Coax Cable In
Program Source (2) Antenna
Source Input (2) Coax Antenna In

and cable guide data still showing.

Did another call in on the network, another reboot and same as above - nag about rerunning guided setup but one button press gets out of that.

So the cable cards weren't paired to the box. in fact the cards weren't even active. But I think they need to be in order to receive the qam channel map from comcast, i.e. channel 8 is on 249000KHz, etc. in other words, without an active card I don't think it will pull the channel map from comcast and hangs, although am doing another reboot and can do a channel scan of both ota and basic cable to see if there is clear qam it will pick up.

but at this point I am getting two tuners with no cards inserted after running GS choosing OTA & Cable. Will see if it breaks. if it doesn't, then down line I presumable insert cards and pair without having to rerun GS.

Although I did foul up the remote. didn't run GS with the original S3 remote that looks like this:
http://cdn.ubergizmo.com/photos/2006/11/tivo-glo-remote.jpg

grabbed it later and S3 isn't responding to it in dvr 1 or 2 postion on slide switch. I've got ir database 746 and Remote Address: Not Set (0). Think I've fixed that before but it's been a *long* time. but I do want to be able to set the switch to dvr2 so the ir signal doesn't go to other tivos.

am also wondering if you lose metadata if transferring programs between S4 and higher to S3 and back to S4, S5, S6 with direct tivo to tivo transfer.

I've got the dual configuration up and running - both ota & cable - and without cards.

Can someone compare the internal tuners of a Premiere with the S3 Oled 648 to shed some light on these questions. Is this the case?

Series 4 (Premiere) has 2 physical tuners, but they are hybrid and can tune both ntsc/atsc and qam. The tuners are not assigned or locked to any input. Nothing is dedicated. The ant & cable rf inputs feed to both tuners.

Whereas the S3 is different than the premiere in that the tuners are assigned/dedicated/locked to a particular rf input. So internally are there 4 physical tuners total for an S3. A pair dedicated to ota, and a pair dedicated to qam. This may be the case for TivoHD (TSN prefix of 652 or 658) as well.

So the signal on the rf ANT input is physically going to a different pair of tuners on the s3 which are ntsc/atsc only tuners? What happens if you connect cable qam to the rf ANT input? doesn't see anything, right? those tuners are completely blind to qam, right? In other words, it's not a backdoor to gain extra tuners. And those aren't hybrid tuners like in the premiere, right? You can't somehow gain extra tuners for cable on S3 or Tivo HD.

Or conversely can you feed ota to the cable rf input? Or is that pointless since the tuner pair dedicated to the cable rf input are qam only and blind to ntsc/atsc ota frequencies.

And you can't record 2 ota and 2 cable simultaneously on an S3 or Tivo HD, right? so are there in fact 4 physical tuners in those models? a pair for ota and a pair for qam? tell me where I'm going wrong.

Another scenario:
If there was clear qam on the cable rf input, you couldn't record that qam signal simultaneous with 2 ota, right? 3 recordings simultaneous in other words.

dianebrat said:

You can never record more than 2 channels, and you can never view more than 2 channels, as much as it'd be a nice hack it won't work due to the limitations of the system.

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Thank You. That makes sense in that the software won't allow you to set 3 simultaneous recordings I presume even if they are utilizing different tuners. And the channel banner will only show 2 tuners you can swap between so I guess it's likewise impossible to buffer 3 shows at once. but hardware-wise, are there 4 physical tuners? a pair of ota and a pair of ntsc/atsc? So it's a software limitation, right?

In the cardless dual tuner configuration I have set up currently, if I connect cable to the cable rf input and antenna ota to the antenna rf input, will the software prevent me from setting recordings on both ota and clear qam? In other words, can I record (or simply buffer) ota and clear qam simultaneously cardless? 1 show ota and 1 show qam simultaneous that is.

I chose the dual config setup mainly so I could install cards later if chose to (depending on how big the mpeg4 migration is). In other words, if lots of channels remain mpeg2 after comcast's pending mpeg4 migration in my market, then I may put cards in. But another thought is that I might distribute a clear qam locally on a modulator and am hoping to confirm that the S3 could pick that up too in addition to the ota that it does a nice job on.

And the reason I'm going S3 is that it has the best ota tuner of any tivo model with dual rf inputs, unless someone can tell me differently. So if I distribute my own qam locally I don't have to worry about merging it into unused ota frequency since the S3 has separate ant & cable rf inputs.

I can't say that so far I've noticed any real difference in the 648 and 652/658 OTA tuners, but I'm only just getting started playing with those.


I discovered something by chance on the 652/658 cable tuners.

Bought a used 652 a while back, but I didn't get it soon enough to tell anything about the analog OTA tuning, 'cause by then the changeover had happened.

Digital OTA seemed okay considering I only tested it with rabbit ears.

But on analog cable only one of the tuners worked, the other could never lock in, never even showed a brief flash of a picture.

So I thought I'd be stuck using it only as an OTA machine.

Well, the TWC changeover to all digital happened, and I had a fistful of Multi-stream cable cards to put in various TiVos, so just out of curiosity I put one in this particular 652, and it turns out it can tune 2 digital cable channels simultaneously just fine.

So maybe if analog OTA channels were still a thing it'd only have been able to do them on only one tuner.

Without a schematic, or at least a good block diagram, I don't really know if both cable and OTA tuners share NTSC de-modulators or not, or if they share digital demods or not.

unitron said:

I can't say that so far I've noticed any real difference in the 648 and 652/658 OTA tuners, but I'm only just getting started playing with those.

it can tune 2 digital cable channels simultaneously just fine.

Without a schematic, or at least a good block diagram, I don't really know if both cable and OTA tuners share NTSC de-modulators or not, or if they share digital demods or not.

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thanks. I tested 648 vs 652 quite a bit about 5 years ago for ota and 648 was the clear winner. Did some research on this board and that was the consensus as well IIRC. with some digging those posts can be found. And the S3 even beat out the premiere in what wasn't a close contest. in my case there is some multipath to deal with so of course with ota individual results vary. but maybe that's a big factor in my results - multipath - with the 648 handling it well and locking in, and 652 and premiere dropping in and out of lock.

As far as the internals of the 648 and 652 and the tuner details, that info is probably on this board too with enough digging. I've probably seen it before but a long time ago when those models got discussed still in the pre-roamio days.

as far as the cards, as soon as you put one card in, you lose ota due to the way the configuration is setup. So I'm trying to pick up dual tuner ota plus clear qam if it can be done, not that there is anything on clear qam, unless I modulate my own distributed locally which I'm contemplating.

Anybody done dual ota + clear qam on S3 or TivoHD?

tivoyahoo said:

So I'm trying to pick up dual tuner ota plus clear qam if it can be done, not that there is anything on clear qam

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I've been able to confirm that this works. dual configuration of ota+clear qam cable on the S3 648 in dual tuner mode as I've described in prior post. comcast does have a few clear qam digital (not analog) cable channels that I was able to test. so running cardless, you can use the dual tuners to tune:

a) an ota + a digital clear qam
b) two ota channels
c) two digital clear qam channels

so now I am wanting to confirm this:

worachj said:

If you run guided setup on the 648 for Cable or OTA&Cable, you will need two cable cards for two tuner capabilities.

The 648 takes two cable cards, and will revert to single tuner mode if you only have one cable card, even for the OTA tuners. With two cable cards you can record/use any combination of two OTA/Cable tuners.

Click to expand...

so with 2 active cards, you can tune:
a) an ota + a digital cable
b) two ota channels
c) two digital cable channels

Is the above correct? or does the S3 648 revert to digital cable only once cards are inserted and you lose ota in that scenario?