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Perhaps your cable box has a IEEE1394 port. If so, you might be able to record the digital signal using VirtualDVHS

8.12 gigs an hour. But you can always strip out the ads with a tool like MPEG Streamclip. Then your only problem is how to archive the still-massive file. =)

Also: shameless plug for my HDTV recording page and VirtualDVHS.

On the same note, I have a modified version of VirtualDVHS (sans source, I deleted it all accidentally, oops) that has fast forward and rewind support. Although I captured the commands off a Mitsubishi HDTV (Mits sets with tuners have built-in FireWire - can't beat it), it should work with the 165. You can find it here.

(I swear on my future children and a sacred monkey that I'll be working on it again soon! Updates are good...)

Now if someone can figure out how to send the MPEG transport stream back to the digital cable box for playback...

The 6200 I was playing with was incapable of such a task - it had an output channel, but no input channel. Unfortunately I don't have it anymore since I do all my recording OTA and I don't have cable. With OTA tuners you can send the stream back to the tuner and have it play in all its high definition glory on a widescreen TV.

This guy beat me to an application; all I have to show is a modified version of VirtualDVHS that responds to remote control commands from a Mits integrated HDTV. See it here. It basically pretends to be a VCR and uses the TV's internal event timer to do recordings.

Only if the mac owner owns a powermac g5 because its the only mac that can play back 1920x1080 mpeg2 files.

Which is why the method I use with an old 266 G3 is preferable to me: the HD stream is recorded on the computer, but the TV's tuner does all the decoding work. Granted, I'm doing OTA recording, but that's what I watch so that's what I do.

I've been doing this for about a year already; with existing hardware. Firewire to Mits TV and I'm recording. Works with any FireWire enabled HDTV tuner out there.

The hard part is the mpeg decoding, which, I assume in this guy's case, is handled by a dedicated decoder chip on the firewire device.

Correct; I'm just using the G3 to store the stream. The tuner does all the hard work. My notes on the setup are here.

This is pretty neat, but it appears to fall short of being able to just capture the ATSC stream and play it back unmodified to the TV.

Not everyone needs mad power hardware or cards to decode the MPEG2 stream and output it. Some HD tuners, like those included in the Mitsubishi HD sets, have FireWire jacks that are capable of feeding the transport stream to something (typically a D-VHS deck) and accepting a transport stream back from a device.

Apple has released a sample application with their FireWire SDK for MacOS X called VirtualDVHS that I've been playing with. My notes on it are here. The FireWire enabled tuner does all the work, including sending start/stop commands to the device, and on Mits sets, timer recordings.

It's a great little program, and since it's a SDK, you get all the source code for it and the FireWire drivers. The TV's remote control works (commands sent via the FireWire interface) and here's the best part: it works on a dead slow stock CPU G3 266. This computer can't even play simple QuickTime movies properly, yet it works like a charm because all it does is capture and stream back the MPEG2 transport stream. The tuner's decoder does all the hard work.

Okay, so it isn't a PVR with nifty features and whatnot, nor will it work if you don't have a tuner with FireWire jacks. But I don't care too much about the PVR features for the moment because there isn't enough OTA HD programming yet. All I need it to do is time shift a few programs each week when I'll have to be at work, or busy with school, or whatnot.

VirtualDVHS may be a ghetto program, but it gives you a glimpse of what you can do with MPEG2 streams. No special ATSC cards required. And hey, you get the source: make it do more of what you want and tell people about it, or write your own.