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Second Generation Homebrew PVR Devices
An anonymous reader writes "It looks like the second generation of homebrew PVRs is on its way. Asus recently released their Digimatrix barebones PC which combines a lot of features in a very slim and stylish box. DVD/CD-R, WiFi, HDTV tuner, FM Tuner, memory card reader etc. All for ~$400. The reviews look good, except that the software that comes with it doesn't look all that great... of course this may not be a problem because there has already been significant effort in getting linux to run on it and most features are working. Combine MythTV with this device and you have an almost perfect PVR? I wonder what other hardware companies have in store for the homebrew PVR market?"
With a Pentium IV and a fast system bus, I would expect this thing to draw a lot of power. When I went from an Athlon based system to an iMac, my power bill dropped by almost ten bucks a month. I'd hate to see it spike from a set top appliance.
But for now at least we still have to put up with either a rather large Media PC, one that doesn't quite fit in with the other components of your home theater I mean, or whatever PoS companies like Sony want to jam down our throats this model year.
So to make a long story short I would like to see a Computer that looks, and feels, like a super slim DVD player, and Runs Linux. Not too much to ask I think, and then I would be able to do as I please with it.
Disclaimer: If something like this actually exists please let me know about it. I have, after all, been living in the middle of nowhere northern BC for about 19 years.
That really is my homepage, no kidding.
Combine MythTV with this device and you have an almost perfect PVR?
I have a fair bit of experience with MythTV. I've been using it for around 6 months now with both a Bt878 card and a PVR-350. And I wouldn't say "almost perfect". Pretty nice/cool, yes, but far from perfect. A friend has a TiVo that we use a lot.
Here are some thoughts:
MythTV/PVR can be somewhat cheaper (and big/ugly) or it can be quite a bit more expensive than a TiVo when using a nice case like in this article.
TiVo subscription fees suck.
MythTV and/or the PVR drivers crash or flake out. Some times I get interference bars across the recordings, a reboot fixes it. Not all the time, but sometimes. TiVo don't crash.
MythTV can run multiple tuners. Although not really that great a bonus. I used to run several tuners but I never watched all the crap it recorded anyway. I'm using one tuner now and that's more than enough.
MythTV can be daunting to install and configure. It takes a lot of time. There is KnoppMyth which is pretty easy and preconfigured, but it doesn't always work and still requires some configuration.
MythTV makes it "easy" (if you ignore configuration pain) to use remote frontends so you can watch TV on any computer on the network.
MythTV makes it easy to burn DVD's of your recorded shows or save the video for archival purposes.
Just use slow spinning 120mm, 92mm, and 80mm fans rather than fast spinning 70mm and 40mm fans.
My microATX system runs with a 120mm fan in its ATX power supply. When idle it spins at about 1,000 RPM's. It's maximum rating is 2,000 RPM's. It self adjusts depending on load. That is less than 20db once the case is closed up.
Then I modded that same case for a 120mm fan in the front of it (from the normal 80mm fan) and I run it at 1,200 RPM's (I use a rheostat to adjust its voltage/RPM). Then I use a 92->80mm fan adapter on the cpu heatsink with a large Alpha 8045 (80x80x45mm) heatsink with copper inlay. This fan runs at about 1,000 RPM's, but it has a heat sensor on a wire that I can place anywhere. I chose to tape it to the side of the heatsink and that keeps the fan at about 1,800 RPM's under load and 1,000 RPM's idle. If you tape the thermal sensor for this fan to another area, it will run at a slower or faster rate, depending on how hot that surface gets.
Then I modded the back of the case (click on the "back view" to see it) to allow a 92mm fan in there rather than 80mm. I run it at 1,000 RPM's.
Now, every fan in a normal default factory case runs at about 2,500-4,000 RPM's by default and are only 60-80mm wide. A 120mm fan at 1,000 RPM's pushes the same amount of air (provided there is little restriction in the airflow pathway, and the shape of the finns, but on average...) as an 80mm fan running at 3,000 RPM's.
Also, using the built in fan grill in your case (the ones they just punch out small holes in a pattern the shape of 60 or 80mm fan) is the worst thing you can do, even if you are going to use default sizes. You should always dremel out the built in grill and use a standard wire grill rather than those fancy air restricting/turbulence creating grills.
Then use a 5400RPM Hard drive. If you want to blow money you can even get a heatpipe cooler for your hard drive that screws into a 5.25in bay with rubber washers, and isolates the HDD from the case. Then the heatpipes keep the drive cool. This works up to even with 10krpm drives. But I use 7200RPM's on my desktop systems.
That is the basics. On top of all this you can do even more: Rubber washers between each fan and the case to prevent oscilations. If you use 2 identical fans, don't allow them to both run at the same voltage, as they will give you a beating effect because they will never spin at EXACTLY the same rate (unless you buy expensive computer controlled fan regulators which are only available in servers). Put a rubber washer between the power supply and the back of the case before screwing it in. Then put thin padding on all the joints of the case (like where the side pannel touches the rest of the case). This will dampen the oscillations throughout the case, and regulate all oscillations to be contained in a single pannel, rather than the entire case.
There is much more you can do, but this post is getting long. You handy people should get modding. You don't have to be fancy and rice out your case with glowing lights to be a case modder. I don't, and my mods are what draws the attention when my friends compare computer systems with eachother. They just don't see how I can pack the fastest video card, the fastest CPU, and the best everything in such a small case, overclocked, and still keep it quieter than a Mac G5.
Your ignorance is infinitely greater than you realize.
As I'm sure we all know, upgradability is a big issue with computer hardware. My MythTV box is using a Cooler Master case (but in black), with this motherboard.
I've already added a DVB-T (HDTV in the US) card, which you can't do with this box (i.e. you will never get digital TV with this box).
My box is a bit bigger, but looks like a stereo component (brushed steel). I'm also planning on adding an extra analogue capture card (bringing my capture sources up to three). This will fill the PCI slots on the Micro-ATX board, so I'm damn glad I didn't buy a smaller box!
I've got a DVD-ROM drive, DVD burner and currently one 160GB hard disk. Planning on adding another much bigger hard drive (waiting, waiting, I want 1TB)
If you are thinking of building a PVR (it's a fun project), you really should think about expandability and upgradability.
Also check Jarod's PVR Hardware Database, and his excellent Install Guides page.
Also, don't forget MythTV is a very nice client/server architecture, so you can run your "backend" on some beefy ugly PC in a cupboard, and us anything (including an XBox) as a frontend.
--
"Puritanism - the haunting fear that someone, somewhere, may be happy."
-- Henry Mencken
My blog: http://yi.org/blog, Latest entry : Muscle powered microrobot's