User Manual:Setting Up

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In this context, by "setting up" we mean "here's this box on the counter; how do I connect it to the outside world?"

Please note: some things will be explained somewhat in-depth here, for the benefit of users who may not be as technically astute as others.

Any given MythBox will likely have these connections to the outside world:

  • AC power
  • Video out
  • Audio out
  • Video source(s)
  • Networking

Let's talk about each of these connections and what you do with it.

Additional information about setting up High Definition systems can be found at Configuring HDTV.


AC power

Electronics tend not to work well without electricity. Exactly what this will want depends (as will so many other things we'll talk about when we get to them) on the choices made by whomever built your Box, but it will commonly be "that computer power cord".

That connector is called an "IEC connector", and it's usable at all voltages, with the appropriate power supply; it's likely (though not certain) that whomever built your box set it to 120 or 240 VAC already, but it never hurts to check — some power supplies don't have a switch; they're good all the way from 100 to 250 volts automatically.

Since your MythBox needs to be running at all times, to be able to record scheduled programs at inconvenient hours, it's a very good idea to plug the power cord into a UPS — an Uninterruptible Power Supply, or 'battery backup'. It's likely this should be one with surge suppression, just because that's a good idea, and probably one with surge suppression not only for the power, but for the TV cable, too, if you're using cable TV to feed your box.

At the very least, you should have your MythBox plugged into a good surge protector — there's almost surely a nice sum of money tied up in your MythBox, and a good surge protector is cheap insurance.

Graphics cards

To connect our MythBox to a display we need to have a graphics card.

We have three main choices today. ATI, Nvidia and Via Unichrome. Some of you may have Matrox cards which have good Linux support, but are harder to find.

Via Unichrome

The Unichrome tends to be built into motherboards these days especially the small form factor MiniITX motherboards and PC's.

ATI and Nvidia

Both ATI and Nvidia have not yet released their drivers as OpenSource. These are only available as proprietary binaries which can be downloaded from the ATI and Nvidia web sites.

Video acceleration

This has become much more important now with HDTV and HD Video. The two key hardware features we are interested in are Xv and XvMC. Linux graphics desktops make use of the Xwindow system from MIT.

Xv and video acceleration

Xv is an extension to X (the X window system) that provides for video integration into the desktop environment. Basically X provides a rectangular window that video devices can render the video into. The rendering of this video window will be hardware assisted with the correct drivers installed.

XvMC X video motion compensation

XvMC is an extension to Xv that allows for hardware acceleration of the Video in the Xv window for MPEG video streams. This is especially needed with DVD's and DVB broadcast streams because these video streams are typically compressed like zip files and need to be decompressed before they can be displayed. Both DVD and DVB use MPEG-2 as the Video compression. XvMC provides hardware decompression of MPEG-2 video streams.

The good news is that MythTV as of 0.18.1 now supports XvMC, though there are still problems with on screen menus flashing when XvMC is enabled

As of January 2006 there is no XvMC support for ATI cards, but we do have XvMC for Nvidia and Unichrome.

Connecting your display

There are several methods you can use to connect your MythBox to your display, whatever it may be (e.g. monitor, TV, etc):

Composite TV out

Composite.png

This provides an NTSC (or PAL) standard video output signal, which can be sent to a normal TV set using a normal RCA cable.

If your box has NTSC/PAL video out, you'll find an RCA video connector (usually yellow), or a 4-pin Mini-DIN S-Video connector on the back somewhere, which you can connect your monitor to, with the appropriate cable.

VGA output

Vga.png

This can be sent either to a CRT monitor, an LCD or plasma flat-panel, or a projector. If you have a satisfactorily large monitor, you might find this a better solution; most such monitors and projectors will accept the higher scan-rate signal that a composite output provides.

If you are going to use VGA then you will use an HD-15 cable up to the VGA connector which you will find on the back panel.

Component video

Component.png

This will require a VGA to component adapter and a video card that supports component out. Component video offers the best quality for an analog signal.

You can also use the Component-Out feature on some nVidia Cards. (I use the 6600GT and it works great) Read my how-to Here

DVI digital connection

Dvi.png

For the best quality, especially to modern digital displays such as big-screen LCD, plasma or micro projection solutions, this is the preferred option. Note that DVI has both digital and analog or combined versions on the same connector. The analog version is compatible with VGA (using an adapter). The digital section is compatible with the latest HDMI connector found on some Hi-Def displays.

Be aware that some of the latest digital displays have hardware content protection built in.

HDMI

Hdmi.png

This is a more modern version of DVI and is technically backwards compatible. It uses a smaller more manageable connector. You can get an HDMI to DVI adaptor if you need to connect your PC graphics card DVI connector to the latest HDMI displays. The latest HDMI connections will also be able to carry digital multi-channel audio down the same cable.

Audio out

There are two options to connect the audio out from your MythBox to your amplifier, TV, or powered speakers.

Analog

This is almost always the standard 3.5mm stereo audio jack that most sound cards have, and indeed, the sound card (or onboard audio) of your box is where the audio comes out.

Advanced configurations may support multi-channel (surround) sound making use of the surround sound decoder on your sound card. Typically this will be 5.1 or 7.1 channels of surround sound, the first number denoting the number of speakers/channels and ".1" denoting the subwoofer channel.

Digital

This is the best option if you are after absolute sound quality. This will be via a SPDIF optical or coaxial connector from your sound card direct to your home theatre surround sound amplifier or receiver. The decoding of the surround sound is done external to your MythBox.

You may find it helpful to read the section on Sound card.

Video sources

RF tuner

This is done via the threaded "F-connector" or coaxial connector on your tuner card(s), into which you connect the cable from your cable TV feed or outside antenna. If you have more than one tuner card, you'll need a splitter and some jumpers to hook everything up. (Note: in Europe (and maybe other places), you may not have an "F-connector," and it may or may not be threaded.)

If you're recording HDTV or satellite TV signals, there may be special considerations about cabling and tuner cards.

Other capture card inputs

Most tuner or capture cards will allow you to capture not only RF signals from your antenna or cable TV provider, but also locally generated video signals, be they from a VCR, a DVD player (though there are better ways to accomplish this) a LaserDisc player (and alas, there aren't better ways to accomplish this), or a cable box or satellite receiver, for channels you can't get a tuner card to tune directly. More later on this, too.

The input jacks for this, both video and audio, will usually (always?) be on the tuner card itself, in the card cage, as opposed to the video, VGA, and audio-out connectors, which are usually on the motherboard these days (in a section called the "ATX backplane").

You can find a list of capture cards that work with MythTV in the video capture card section.

Storage

As this is a significant topic you might find it helpful to read the section on file storage.

In the event that you want to add fault tolerance and redundancy to your storage then you should read the section on RAID.

Networking

If you have a standalone MythBox, then you might not ever connect to a network, though this is highly unlikely.

Myth supports multiple front-end machines (for controlling TV's in different rooms) and multiple back-end machines (for splitting up storage, transcode/commercial marking and tuner support), and you connect all of these through a network, preferably using 100-Base-T or Gigabit Ethernet.

In addition, extension modules like MythWeb, MythWeather, and MythBrowser require Internet access. (Actually, MythWeb doesn't need the Internet, just a network connection.)

The biggest reason you will connect to the network is because (most of the time) MythTV gets its program guide data over the Internet. Program guide data is the information in the program guide grids, that allows MythTV most of its PVR functions, like scheduled recordings, etc.

If you are making your MythBox accessible from the outside world, you should almost certainly put it behind a router, and possibly investigate the firewall features of your Linux operating system.

If that's too complicated for you to understand at the moment, then ask a geek for help, or don't open outside-world connections to your box yet.

Ethernet

Most of the time, you'll network your MythBox via Ethernet. The standard jack and plug for this is known as RJ-45, and it looks slightly wider than a telephone jack and has 8 pins (telephone/RJ-15 has 2 or 4 pins). If you have broadband, you most likely use an Ethernet cable to connect to the Internet.

Wireless

If you don't happen to have Ethernet strung around your house, you could use Wi-Fi, or 802.11b/g. 802.11b provides speeds up to 11 Mbits/s and 802.11g provides up to 54 Mbits/sec. Wi-Fi is slightly more difficult to set up than regular Ethernet, just because Linux drivers are usually less mature, so you must check and ensure that the 802.11b/g card that you buy supports Linux before buying it. Oh, and you'll need a wireless router too. Those are cheap these days. Once you have that up, you don't need Ethernet run to the box(es) anymore, which is great!

If you're planning multiple frontend/backend boxes, you will probably find 802.11b far too slow for acceptable playback. Since 802.11g provides much faster speeds, it should work much better for this purpose.

Remote controls

There are three options for getting remote controls working under Linux

Linux Infrared Control (LIRC)

LIRC provides the software interface between an Infrared Receiver and MythTV. Most modern distributions will have this as standard. It provides great flexibility in mapping infrared remote control keys to MythTV functions. The downside of using LIRC is that you need to get an Infrared Receiver. The easiest way to do this is to buy the Microsoft MCE remote and receiver bundle which is quite low cost. Several popular tuner cards, for example the Hauppauge PVR-150, also come with a built-in IR receiver.

See the Remote Controls category for information on different remote models.

Infrared Keyboard emulation

This is probably the easiest way of getting a remote control to work with MythTV. You simply teach a learning remote such as any of the popular One 4 All or Logitech Remotes the keys from your keyboard and hey presto your remote now does exactly what your keyboard does. It's interesting to note that the official Microsoft Media Centre Keyboard is an infrared keyboard but is not yet supported under Linux.

WI-FI Remote plugin

There is now a plugin that provides a web remote front end that can be displayed on a PDA to remote control your Myth Frontend.

http://studwww.ugent.be/~aveys/mythwifi/

Cable/Satellite Box Control

IR

For infrared (ir) output to your cable or satellite box use an IR Blaster.

Serial

Some cable and satellite boxes have serial ports that can be used to control them. See Motorola DCT-25xx.

Firewire

If you cable or satellite box has firewire then you can use firewire to change channels and even capture video (if it is enabled). See FireWire.

Wireless keyboards

Once your Myth box has been setup you wont need to use your keyboard that much. Many users will often just SSH into their machine or use a remote desktop such as VNC to get access. Of course its also nice to have a keyboard directly connected, in which case a wireless keyboard is preferred. Have a look at the section on Wireless Keyboards to see which ones work.



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