Project Myth [pt1]
I started cooking up Project Myth after I discovered you can get a DVB-T(Digital Video Broadcasting-Terrestrial) USB stick for £30. Everybody probably knew this already, I was just too lazy to find out. I haven’t had a tv tuner card since the 20th century when they cost £100’s.
This comes with a remote and antenna.
This £30 stick is hopefully going to be the basis of my new, thrifty (cheapskate) home cinema setup.
We have a living room (lounge). However, the feed into it is via a primitive ’sky’ ’satellite’ mechanism. There’s also something called ‘DVD’ but I don’t have any of the silver tokens that it apparently requires.
Hence, we tend to huddle in our tiny office watching media on our computers. Not an ideal situation. After ruminating on the subject on and off for several months, I decided to do something about it. One of the main motivators was cost. Here we plunge into the world of A/V (Audio/Video) arcanery, which I once had an interest in.
The hardware
I’m going to run this on a small mini-ITX Via C7 system, which is surplus after our PBX tinkering. Because I don’t have a big enough CF card, it’s using a noisy ancient 10gb disk which will probably die soon. Cost: £0.
MythTV
I’m not particularly interested in compiling and/or getting MythTV working, so I used the Mythbuntu ubuntu clone distro. This installed very simply and the MythTV frontend came up after the system booted. So far so good.
TV-Out
So the whole point of this mythbox is to be able to watch avi’s in the living room, on the tv. Luckily the Via CN-series motherboard that I have appeared to have TV-Out support. A bit of digging revealed that this is a ViaChrome graphics chip. There is a driver named OpenChrome which I installed following the instructions here.
To get TV-Out working on my UK PAL TV, I had to insert the following into my xorg.conf:
In section “Device” :
Option "TVType" "PAL"Option "TVOutput" "Composite"
In section “Screen”, subsection “Display”:
Modes "720x576" "720x576Noscale"
Connection methods
You’ll notice ‘Composite’ in the above xorg config snippet. The wikipedia has a good overview of the connectors you’re likely to encounter.
The TV-out on your video card is probably going to be one (or both) of these two:
A reasonably high-end TV should have this input. Use it if you can, it’s higher quality than Composite as the colour and brightness signals are transmitted seperately.
Combines colour and brightness into one signal. The quality isn’t great for text or menus but it’s absolutely fine for video. Considering the likely quality of a TV that only has composite input, it won’t make any difference anyway.
If your TV has neither of these inputs and only SCART, that’s no problem as SCART is more of a meta-connector that can handle lots of inputs. Adapters are available cheaply to interface either Composite or S-Video to SCART:
This one lets you shove S-Video or composite into a SCART input.
If your TV-Out has more advanced outputs such as Component or HDMI, you’re on your own as you’ve clearly Spent Money, which is against the spirit of this post.
My connection
I used Composite connected to a SCART adapter like the above I had lying around. I used composite because that’s the cable that I found lying around. Cost £0.
Audio
This is really simple. Just connect the Miniplug output of your sound card/onboard sound to the audio input jacks either on the front of the TV or in the right socket on the SCART adapter. I found a cable lying around which did just that, with a headphones style socket on one end and two RCA jacks on the other. Cost £0.
That’s the hardware stuff taken care of. In a later article I’ll talk about getting MythTV actually working. If you’re good. Maybe.
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