I realize this will be highly subjective, but I'm looking to take the dip into a MythTV HDTV "build".

I see the list of cards supported (pcHDTV, Air2PC--although doesn't appear to support NTSC?--and DVico) seem to be the top 3 vendors.

All I want to use this for at this point is "dedicated" HDTV via QAM on TW Digital Cable (basically only my locals will get recorded).

Whichever one is supported "best" (meaning less hassle to setup/configure AND doesn't drop frames, etc.). I see some "possible" bad things about the pcHDTV cards (gripes on the forums), but it doesn't seem like a lot of people use the DVICO Fusion HDTV 5 series either.

Oh, this will also be used with an Athlon64 CPU (not a dual core), if that matters.

It matters greatly. I spent quite some time fighting a DVICO Fusion HDTV5 RT Lite in a system with a 2Ghz Celeron and 256Mb RAM - Wouldn't play HD back without dropping frames, choppy audio, etc. I had some settings issues (you can follow the "fun" here if you like http://mysettopbox.tv/phpBB2/viewtopic.php?t=12629), but after clearing some entries in the DB and throwing a better mobo/faster (slightly) CPU at it it works fine. I still have occasional dropped frames but I believe that is because I'm underpowered on the CPU side, and am planning on upgrading in a month or so. Take a look through the Tier 1/2 forums to get an idea of the hardware folks are using for HDTV playback.

Anyway, the Fusion HDTV5 RT Lite works out of the box on my R5D1 + 0.20 installation, giving me HD channels from my BrightHouse (Time Warner affiliate here in Detroit area) basic cable connection.

I hear the HDHomeRun works really well with QAM. I'm only using OTA for mine and it works great. No hardware to fight as long as you can get your network card up. Plus it's dual tuner.

Thanks. Only thing I'm wondering though is how well can it pipe HDTV (even dual tuner) over a 100 MB connection? (even switched). Gigabit, I could see (maybe).

Sounds similar to "streaming" like the Slingbox (sorry, too pixelated and jumpy for me even at 100 MB for SD TV, let alone 1080i HDTV or 720p).

The Dragon v1.1 spec has an Athlon64 and uses the AirStar HD5000AV cards. I know that they work well. I haven't worked with or tested the latest pcHDTV cards or the DVICO cards.

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The current maximum bandwidth that an hd stream will use is 19.39mbs. The network connection is 100mbs. Two steams will be 38.78mbs. This is less than half the connections bandwidth. Should have no problems using this device and really you could theoretically have up too 5 steams inbound and 5 streams outbound at once. So even if you have a backend with 100mbs full duplex connection (this is the norm these days) and want to record/watch two hd shows on different frontends you would be using 38.78mbs inbound and 38.78mbs outbound. Both directions you would still have 61.22mbs left for other traffic and this would be a worse case scenario.

Now to show how this device can scale, let’s look at this scenario.

Backend connected to a 1gbs switch. You connect 25 of these devices to different ports on that switch. Each device will use 38.78mbs and will be connected to the switch with a 100mbs connection. The switch will forward all the packets to the backend utilizing 969.5mbs. You will be recording 50 HD shows at once. LOL and it should work. At the same time you could also watch 50 shows on different front ends. Of course this is only if the only limitation is network bandwidth. I would hate to have to buy the drives to hold all that and that could read and right simultaneously at a 100MBs (a raid5 array of 8 750GB SATA would work) and forget about commflaging.

A couple things to note;
To keep it simple I haven’t factored in protocol overhead, though it would not be much.
Also the size of the HD steam I'm using is its max it can be smaller.


Now I just need to buy one of these.

Although keep in mind the 100Mb is a theoretical max. I believe ethernet pretty much becomes "crappy" at about 25% saturation. (in other words, ethernet is usually considered saturated at 25% capacity).

Gigabit doesn't get you anything since the adapter on the HDHomeRun is 100MB (if it was gigabit, you'd get additional throughput on multiple streams, but it's not like a factor of 10).

I guess all I need to know now is:

30 day money back guarantee?
and:

Can I hook a digital STB up to it (ie, setup just like a Series 2 DT Tivo). One input controls the QAM signal from the cable feed directly, the other input is being fed by the coax output of the digital STB and controlled via IR Blaster.

If not, then I'm probably better off just using the AirStar card for HD and an MPEG2 card for the digital STB.

Depends somewhat on the usage pattern. On a small LAN, transfering between two active hosts, with any other machines at minimal usage, you can push the throughput right up to the theoretical limits. Before upgrading my LAN to a Gigabit switch, big file transfers between the two main machines would run at very, very close to 100Mbit/s. With the GigE switch and jumbo frames the limiting factor is the speed of the PATA disks at either end. I can copy a big file machine to machine faster than I can copy it locally.

Bottom line, without a lot of other competition, you can expect to get near the full bandwidth of the segment. With a store and forward GigE router you ought to be able to get multiple 100Mbit/s sources feeding to a 1Gbit/s reader at nearly full blast.

Unless you are having some type of problem with your equipment you should be able to reach very close to the full 100mbs. If you are running windows use a tool like "Total Copy" and move an iso from one box to another. Look at the transfer rate and you should see it is very close to 100mbs.

Now if you are looking at 802.11a,b,g then that is a different story. What they are rated at and what they can do are very different.




If you are using a gigabit switch you can connect multiple devices at 100mbs and it will aggregate all there packets to the one server connected with gigabit. Do this all the time.




For the STB you would get a better picture using its s-video out to a PVR-X50 card.

Just checked and the HDHomeRun can only receive digital signals. I'm not that familiar with the Tivo but most devices of its type send an analog signal via coax usually ch. 3 or 4.

hope I don't sound argumentative just try to help out.

Ethernet only becomes "crappy" at 25% if you are using a hub, or an incredibly cheap switch. I have done many file transfers at >90Mbps on 100Mbps switches.

A gigabit switch in the layout datobin1 suggested WOULD help out a lot. He didn't mention it, but be obviously meant that the backend would have a 1Gbps network card connected to the gigabit switch. The connection between the switch and the backend is what matters, assuming the devices all have at least a 100Mbps connection to the switch. (Some switches have 100Mbps ports, except for a single or double 1Gbps port. These would work the same in this situation to a full gigabit switch.)

Most consumer gigabit switches network cards can't push through 970Mbps, though 400Mbps is certainly achievable on most. The biggest concern would really be finding a storage array that could write that many simultaneous streams at that bandwidth. Here is an array that will push 800MB/s for a single sequential read. Trying to do 50 simultaneous writes at a total of 120MB/s would be a chore (though the 2GB cache onboard the controller would certainly help).

Don't dismiss the HDHomeRun so quickly. It doesn't encode video like the Slingbox. All it does is take the MPEG-2 being broadcast over the air or cable and send it strait over Ethernet to your MythTV box. And because it doesn't sit in your PCI slot, there are no resource conflicts, space issues, heat issues, etc that you have to deal with inside the computer case. You can also place the HDHomeRun much closer to whatever source you are going to use as it doesn't have to be wherever the backend is. Oh, and as mentioned, there isn't a practical limit to how many you can have.

If I determine that I can actually get free digital cable over our crappy cable lines, I'm probably going to pick up one of those boxes.

No problem. I appreciate the input. I guess if the MythTV "box" (Asus Pundit in my case) was hooked up to gigabit AND the HDHomeRun had gigabit, then I'd get better throughput (but it's only got a single 100MB card).

I've just seen the slingbox, and IMO, it performs crappy. Jerky, pixelation, etc. And that's not even doing HDTV.

I would certainly rather use an external "thing" (ie, HDHomeRun) than internal cards (seems easier to setup and no CPU overhead with the HD signal, yes?).

But I don't want to spend $170 on it only to find out I can only use the one tuner for "direct" cable connect and then have to go and buy another PCI card for the STB anyway.

The analogy with the Tivo Series 2 DT is that the DT unit has a coaxial input (just like the HDHomeRun) and you connect your "analog" cable to that. But, it also has another set of inputs (svideo, composite, and I think another RF input) that has NO tuner. That accepts input from the STB. You split your cable with a "y" adapter and connect one to the Tivo and the other to the cable box and then your S-video/composite cables to the Tivo.

But I don't know if the HDHomeRun can do that or if "it" must do the tuning (ie, no way to connect a STB to the device).

However, I am "heartened" that the Dragon uses the AirStation 5000, so that seems to be a good card to get (if needbe) for HD and then I could get another card (later if I needed to) for the Digital STB stuff with the hardware encoding (lighten up the CPU a bit).

http://www.intel.com/network/connectivi ... review.pdf

Guess the Broadcom didn't fare so well.

There is no way to connect a set top box to the HDHomeRun. The HDHomeRun can only pick up digitally broadcast signals, like over the air HDTV or unencrypted digital channels on cable. In most areas, there are only a couple of digital channels that are unencrypted. In my area with Time Warner, the only unencrypted channels are the same ones that are broadcast over the air in both analog and digital.

If you can get it, pictures typically look much better when broadcast digitally than in analog. For me, the analog channels on cable aren't that clear, so I want one of these boxes for at least a couple of the channels. My problem is that I don't know if the signal is clear enough for the box to even work.

Great, thanks for the confirmation. In my area, the "digital" channels (even if they're not really digital) come in clearer via the STB than over analog.

So I'll use the AirStar HD 5500 to start with and see where it goes from there.

Just to disambiguate, the Dragon uses the AirStar HD5000. The card with 5500 in its name is the pcHDTV HD5500. It's an unfortunate naming convention

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