My Car Media Center Page

After setting up my Media Center in the house, I was very impressed with the way it manages my music. Having all 200 or so of my CD’s available everywhere in my home, and able to make playlists for any or all of them is a great feature. However, at home isn’t where I generally listen to a lot of music. I listen to music in my car.

This got me thinking. Would it be possible to put the full Mediacenter system in my car? I knew I could by car MP3 players etc, but I really like seeing album art. I don’t know why, it is just a thing with me. If there is no album art, it has to be a really awesome CD to make it on to my Mediacenter. After considering a few options, it seemed that putting a PC in the car with a screen was the best option. I live in South Africa, where unfortunately, petty crime such as car break-ins are common place. Therefore, I had to make sure the system I put in wasn’t too obvious. There are several really nice dash mounted screens available, but most of them are prominent, and would get stolen within a couple of days. I then found a in-dash screen which was motorised for about $220 on, which is a Canadian site selling MP3 players and just about every other kind of digital audio equipment. I was planning on going to the USA a month or two after this, so I ordered it and it arrived where I was going to be staying fairly promptly. They had better, more expensive models available, but this was still very much in proof of concept mode, so I didn’t want to over capitalise on a project I wasn’t even sure would work.

I was planning on using a touch screen interface, however this screen was not a touch unit. I ordered a separate touch screen unit for later attachment. Unfortunately, the touch screen kit looked really, really ugly attached. I decided to stick with the remote for now.

I bought a 700W inverter to take care of the power needs. I could have gotten a smaller one but thought I’d err on the safe side. I needed the inverter to be wired via the ignition so that it wouldn’t stay on all the time and run down my battery. Because this is way too much current to run straight through the ignition, I am using a relay to control it. When the ignition is on, the relay is closed which gives power to the inverter. When the ignition turns off, the relay breaks the circuit and the inverter is shut off. After visiting 3 or 4 Auto Electrician (and being amazed at how little they knew about auto electrical stuff and how unwilling they were to try anything interesting), I finally found one who knew what I was talking about, and was willing to do it. Cape Auto Elecrical in Cape Town. I left my car with them for a day, and it was done. I had a problem almost immediatly when I switched the inverter on. It seemed to be working ok, except that it was making a warning siren. Not good. I took it back to them the next day, and they saw that the ground was not good enough. It took them 10 minutes to fix it, then the noise was gone, and everything seemed to be working well.

I bought a 350W PSU for the machine, which I thought should provide plenty of power. I also bought a small UPS. My problem was how to shut the machine down gracefully after an ignition power down. The inverter would just drop the power, which isn’t good. I decided to put a small UPS between the inverter and the PSU so that when the car was on, the UPS would charge, and provide a few minutes of power once the car was off, then when the battery got low, it would send a shutdown signal and the machine would shut down. Sounds good in theory. In practise however, a UPS requires a sinusoidal AC current to charge, and will not charge off simulated digital AC coming from an inverter. I wish someone had told me this before.

To get around this problem I had to run a cable to the console with a non locking press-button switch. This now enables me to put the machine in hibernation mode just before I turn the car off. It takes about 10 seconds to hibernate, which is fine. When I start the car again, I press the button again, and it resumes from hibernation. This actually works better than my previous idea as it enables the machine to resume the playlist it was busy with instead of having to select the CD or playlist again from a complete shutdown. It also means the PC won’t start up automatically, which is better when going on very short journeys.

Please click here for my blog post and pictures of the power setup and installation.

The PC
I had an old full tower case I planned to use because I was going to have a UPS etc, and wanted the unit to be as self-contained as possible. Now that I’m not using a UPS, I am planning on going to a smaller case, but haven’t found one that fits my needs yet. It does use a lot of boot (trunk) space, but to be honest, I don’t care. What good is a space that isn’t filled with cool stuff?

The specs of the machine are as follows:

Gigabyte GA-7VT600 Mainboard, with onboard LAN and Audio
AMD Sempron 2400+ Processor
512MB RAM with a Copper Cooler
Gigabyte 3D Rocket CPU Cooler
350W PSU
Vortex Hard Disk Cooler
Leadtek Geforce FX5200 Graphics Card
40GB IDE Hard Drive (which I will upgrade as I need to)
CD ROM Drive (to become a DVD drive soon!)

The Hard Disk Cooler is really great. It has rubber mounts which absorb a lot of the bumps of driving around with a spinning disk in the boot. It also does a good job of keeping the temperature down. The graphics card has plenty of power for the Media Center application (which is a Direct3D app) and plays videos smoothly. It is passively cooled, so it doesn’t add any noise. The Vortex cooler does a good job as well. This thing is massive, but I haven’t had any heat issues yet, so it must be ok.

The on-board sound card SUCKS! The sound quality really was awful! Unfortunately when you embark on a project like this, it is hard to know where to start troubleshooting sound quality issues. I figured it would most likely be the cables running to the head unit or my dodgy soldering to put female RCA’s on between the head unit and the CD shuttle. After replacing the cables, and checking my solders, I finally decided to try a new sound card. I had an old Sound Blaster Live! which I installed. Immediatly the sound was 100%. No crackles or supression noises or anything. Fantastic. Unfortunately, this created another problem. The PCI sound card would sometimes cause the machine to crash when going over a bump too hard. The reason I knew it was the sound card was that when the machine came up again, it would tell me that no sound hardware was detected. After 3 or 4 reboots, it usually came right. Of course this only ever seemed to happen when I had someone else in the car and was showing my Car Media Center off a bit. That kind of thing keeps you humble I suppose. I finally threw a bit of money at the problem, and it went away. I bought a new Sound Blaster Audigy 2 card for my home PC, and put my Sound Blaster Live! 24bit External sound card in the car, connected via a USB cable. Now, the sound card can bounce around all it wants, and no problems are experienced. And, because it’s a Sound Blaster, it sounds great!

Please click here for my blog post and pictures of the hardware.

Screen and Cabling
Installing the screen was fairly easy. It has standard car radio requirements. The last time I installed a radio or anything in a car was quite a while ago, in quite an old car. My current car proved to be a bit more difficult. Thanks to the car radio thieves, factory fitted radios are very difficult to modify. The cables and connectors are all very unique and it took quite a while to figure it all out. I have radio controls on my steering wheel, which I wasn’t willing to give up, so I couldn’t substitute my head unit. I also wanted to keep the car as standard as I could in case I want to sell it or trade it in. I first tried using an FM modulator as I had heard good things about the Ipod FM Modulator unit. One word of advice. Don’t go there. The sound was terrible. I had to get directly into the head unit. The only way I could get auxillary sound inputs into the head unit was to cut the audio cables coming from my CD Shuttle. My old car had standard RCA’s going to the CD Shuttle. Not anymore. I had to do a trial and error cable cutting exercise to find the audio cables, then solder female RCA connectors to those very small wires.

The only constant power I could get for my screen that was nearby, I later discovered was connected somehow to the dash dimmer control. I had an issue where when the dash was not on full brightness, the screen would switch on and off all the time. I must fix this at some point.

As mentioned above, I also ran a cable with a push button to the front of the car for ATX power control. I also put a USB 2.0 extension cable into the cubby hole (glove box) to which I can attach an extra hard drive, USB Memory, or a USB DVD drive. This works very well.

I did have a picture quality issue early on. It involved what looked like interference lines running up and down the screen. I fixed this by running a wire from the chassis of the PC to the ground cable of the inverter. This ensured that the PC was well grounded, and cleaned the picture right up.

I am using 802.11g Wirless LAN to home. My Car Media Center has a USB WIFI card connected to it also. I use this to update music, copy videos and TV and install MS patches. My home and car Media Centers Music folders syncronise when my car comes into range. A program called My Trigger detects the LAN connection and fires off a program called Synchromagic. Synchromagic checks my Music folder for changes, and copies any files that are new. Over 54Mb, it only takes a few seconds, (unless I have made significant changes, which I usually know about) and have to wait a few minutes for the copy to take place before switching my car off. Windows security updates just download over a few days when the car is on and in range. I just get a notification every couple of weeks that my computer has been updated and needs to reboot. It works very well. If there are any DivX videos or recorded TV programs I might want to watch during heavy traffic, I usually run an extension lead to the car, and plug the PC in to mains. Then I can copy large amounts of data without worrying about battery or petrol.

The Future
Future plans for my Car Media Center include voice activation and GPS. The voice activation should be fairly easy. I plan to install a small mic near the drivers head, similar to a cell phone car kit. I have the XP Plus Media Player Voice Control, and I have tested it, but it isn’t really good enough yet. There is another product called Media Center Communicator by One Voice Technologies which looks like it will do the business. It costs over $100 though, which is very expensive. Maybe they’ll release a cheaper version one day.

GPS is also fairly easy with a USB GPS unit which are easily available here in South Africa. My issue is my screen. It uses a composite RCA video connection like a old TV, and not a VGA connection. The screens with VGA connections were a good deal more expenisive. I found a really nice one with built in touch and VGA connectivity for US$500. A bit much right now. I need to get decent display quality before I can put anything that hasn’t got a good 10ft UI.

Final Comments
Putting this project together has been a lot of fun. It has made me think a lot about overcoming obstacles, and tested my problem resolution skills. It is working beautifully. I haven’t had a single glitch since swapping the sound card. I recently went on a road trip with my wife which was a good 13 or 14 hour drive both ways. We had the Car Media Center on all the time, and the boot was packed tightly with luggage. I was worried a bit about heat and ventilation, but it just worked the whole way. Having hundreds of CD’s and full seasons of TV shows on demand in the car really is amazing. My only problem now is making sure every car I buy from now on is able to have my screen etc fitted.

If anyone else has done this, or is thinking of doing something like this, please let me know. I would love to help you in any way I can.

Please check HERE for all my Car Media Center blog posts.

1 thought on “My Car Media Center Page

  1. Pingback: .chris - a technology blog » Duncan’s podcast on the Media Center Show

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