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media pc

This information dates from 2007

Background

I've always been on the fringe of the technology boom, trying to use modern ideas early without spending big bucks. My interest in satellite TV started way before Sky had launched on Astra, indeed before Astra itself. An old Pace box picked up Discovery, The Children's Channel, CNN and The Learning Channel on Intelsat and Super Channel on Eutelsat. The dish was turned by a windscreen wiper motor and a car jack which was controlled by a home made positioner with a cable remote taken from a defunct video recorder.

Rationale

I started working on a media PC or home theatre PC (HTPC) as they're called a couple of years ago when I realised Sky and TIVO were charging for the technology and HTPC's were starting to appear on the internet, though not at PC World. Not being a big TV watcher I always felt I saw the first five minutes of every crap TV program and the last five minutes of every good one. The ability to have a quick look through the listings and record everything I fancied or a whole series appealed. We also needed an outlet for the digital photos that were clogging the PC. We rarely printed them and those we did hardly ever got looked at, being able to slideshow them could be a good option. Listening to the radio or some music at the same time would be an added bonus and could even free up some living space.

Hardware

Media PC's were and still are huge slabs of metal substantially bigger than HIFI separates or very limited micro systems not capable of expansion and using expensive components. All the commercial ones were loaded with Windows Media Centre, a very limited piece of software. My plan was to achieve a good looking box which could sit under the TV, use standard PC components and be quiet. I had an idea of using my now redundant Mimtec analogue satellite box as a case. It was a full size HIFI width, good looking, in my opinion and available.

In order to package all the required bits I had to do a cut and shut job, extending the case front to back by about 50mm and the height by about 15mm. I also had to weld in the brackets for the drive caddy and cut the vent for the motherboard fan. The back panel was completely new. The photograph shows the later SFX version. (The mess around the vent is silicone mastic to support the fan when it's in place, now replaced by a piece of foam from an old mouse mat).

Noise

It's no good having a PC in the lounge if you can't hear the TV over the fans. That said, our DVD player is very noisy and has more quirks than even Microsoft could dream up! Many people are playing with heat pipes and huge finned cases but I decided early on to use the lowest spec (lowest power) CPU I could get that would do the job and fit the biggest, slowest Zalman fan I could find. I also wanted the air intake to be on the bottom to minimise dust problems. The power supply was going to be passively cooled via a big heatsink on the back.

Video Output

This was my biggest mistake and bugged me for several months.

In Europe the best video out for TV is RGB. (ignoring all the digital stuff since I have a reasonably new 32" widescreen CRT), S-video is an also ran and quiet difficult to find. However video cards only offer S-video or Composite TV out. Matrox are alone in making a video card with RGB out so I duly bought one from Ebay. Unfortunately they are not fully Direct-X 9 compliant and none of the HTPC software would run very well. Finally I called it a day and bought a compliant card. By this time of course I'd bought an AGP motherboard which appears to have all but disappeared now. The nVidia card I bought still isn't trouble free and occasionally screws up the graphics on resume from standby. To get around this problem I've installed a piece of software called 'Hibernate Trigger' and asked it to reboot the PC on resume from standby. This may seem Double Dutch but the theory is this:-

When you schedule a TV program to record, Media Portal wakes the PC from S3 standby, records the program and put it back into standby. Obvoiusly it can't wake the machine from shutdown, nor do I want to leave it fully powered.So Media Portal wakes the machine a few minutes before the program is due to start, Hibernate Trigger detects the wake-up and reboots the machine. Media Portal starts automatically so the program is recorded correctly before the machine goes back into S3 standby. The only problem with this method is that it takes a couple of minutes to get going when you wake the machine with the remote but at least the picture is watchable.

I've tried numerous different drivers and done all I can think of to fix the problem, if anybody has a better idea please let me know...

Power Supply

Most cheap power supplies have two finned tee shaped heat sinks inside. Since they won't fit into the proposed case boxed the board was removed and a finned heatsink bolted on. This appeared to work fine until the unit was bolted in place, after an investigation, it was clear the heatsinks weren't grounded correctly due to poor manufacturing quality.

In use the PSU is partially passively cooled and partially cooled by the Zalman CPU fan.

It worked successfully but eventually I tracked down very random reboots to the PSU and have replaced it with a standard SFX micro ATX PSU. I'm sure this wasn't a cooling related matter since the reboots sometimes occurred from cold but looking at the quality of the manufacturers soldering I should not have installed it in the first place.

Fitting the SFX PSU allowed all the parts to be assembled into the base of the case rather than having the PSU and motherboard mounted on the lid thus making assembly much easier and more standard.

TV Card

Since analogue TV transmissions are about to die in the UK it can be dismissed immediately. DVB-S would be great but Sky encryption isn't easily available, ITV isn't broadcast clear and DVB-S isn't supported by Windows MCE and has modified drivers for other software. That leaves DVB-T as the only easy option. In terms of free TV it's often better than DVB-S anyway as many channels are soft encrypted on the Sky platform.

My Mimtec case however was very low profile and could only fit a low profile card if the bracket was removed. A 90 degree riser card was investigated but extended the card outside the motherboard plan into space that didn't exist either. Being restricted to a low profile card limits the number of options especially as it need to be a 'hardware card' to work with most HTPC software programs and also keep the CPU requirements low.

Drives

Since this was going to sit in the living room and wasn't going to be a PC as such I decided to fit a simple DVD drive and a large hard drive. Anything worth backing up could be done elsewhere as could DVD burning. The priority was space and noise.

I hadn't realised but the length of DVD drives varies quiet a lot, so as well as checking the reviews on noise also keep an eye on the length. Again I used only standard parts not laptop parts.

The hard drive I used was a 250gB serial ATA one. It seemed a good compromise between size and price at the time and the S-ATA cable is much smaller allowing easier routing and better airflow.

Both drives were mounted in a home made caddy which was rubber mounted using isolation mounts from a car ABS modulator which I had to hand.

The front of the DVD drive was modified with an aluminium trim plate and the correct button for the case. Both parts were stuck in place with double sided foam tape.

Motherboard

Micro ATX motherboards are very popular and many full size systems use them, be warned though the actual sizes vary tremendously and almost all are less than the standard size. By now I was quiet limited though, many due to the AGP requirement of the original Matrox G-550 card. I also needed a board that was laid out to allow the use of the big Zalman cooler.

Remote

The TV card actually comes with a remote but I also tried making a remote sensor for the serial port to run with some interface software. Neither were successful. Studying 'professional' HTPC's it became clear everyone was taking the guts out of the Microsoft external receiver and mounting it internally. I eventually did the same and its actually a great solution and a really nice transmitter too.

Final Packaging

I wanted to make the whole unit look like a HIFI separate so it could sit with the amp under the TV. The front panel was very simple having only the DVD tray, 1/4" jacks for headphones and microphones, a pair of USB ports holes for the remote eye, power on light and a power switch.

The front is painted in high gloss black with a polished aluminium centre strip. The lettering is by the old fashioned Letraset rub off transfers. Can you still buy them?

The back panel is also quite simple with remote extender sockets (not used yet), LAN connector, 4 USB ports, TV aerial (F connector), Scart in (composite), DVI (VGA with new card), Scart out (S-video and composite) and audio phonos. The power in connector is to the right of the power supply heat sink.

All these connectors are attached via short jumper leads to the motherboard or cards. The only reason I no longer have DVI out is I can't find a jumper lead and don't fancy making one! (I don't need it yet either).

Network

I had a wireless network and tried using a USB dongle but reception at the back of the TV is fairly poor. Using a HomePlug 'over mains' network has proved an excellent solution.

Final Specification

Overall dimensions 435 x 340 x 85mm (plus 10mm for the rubber feet).

Software

There is actually quiet a number of pieces of software that could do what I wanted and I think I tried every one of the windows ones (well the free ones anyway) because I wanted to run with the Matrox card.

If you haven't found a list these are the ones I tried.

Windows Media Centre 2005 Edition

Media Portal and Media Portal TV Server

Meedio

GB-PVR

Got All Media

The two that stand out are Media Portal and Meedio.

Meedio

Unfortunately Meedio has been sold to Yahoo which isn't available in the UK. The old Meedio is still available through Meedios and has a great interface and a huge number of add in modules. I would have used it if I could have got DVB Radio to work (A module to play the BBC radio streams from the internet works very well). I found the music section easy to follow and the pictures could be tagged via many add in modules.

If they'd got TV card section a bit more sorted this would have been perfect.

MEDIA PORTAL

This is the most capable piece of software BUT the writers are always modifying it. Trying to find a stable version that does all you want is difficult. I guess they are trying to satisfy too many people and never get to a version that does all it was intended properly. Even the stable releases have bug, Leaving the TV picture on top of the album info when switching screens is the most annoying in RC3.

Media Portal TV Server

This is a stand alone unit and works well I think but it's difficult to know where the bugs are. Often I get a frozen screen but the server is still going. You have to stop it to reboot though...

Other Software

I've installed Avast anti-virus protection, Kerio Personal Firewall (old but simple), Tight VNC, to edit the setup from the office PC and Acronic True Image to make a copy when it all goes wrong.

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