Beginner Level Project: Creating a Digital Video Recorder (DVR)
 
Not So Standard Disclaimer Some people who do things to their computers, especially for the first time, destroy them. If you have not destroyed a computer, you should know it is expensive and time-consuming. The destroying part actually just takes a second, but the results can take a long time to fix. Especially if you have to save money to replace the parts you destroyed.

In other words, I am merely showing how I modified my own computer, at my own expense, and at my own risk. If you choose to try the same, it is at your own risk, your own expense, and you are responsible for the results. I take no responsibility for your actions.
Reasons you may choose to create a DVR from an existing computer rather than buying special equipment:
  • Special equipment is expensive
  • Multiple types of special equipment may be needed for the "total experience". I.E. Tivo can record shows, but not burn them to DVD. DVRs can often record shows even from VCRs but still not burn to DVD. A computer DVR, properly equipped, can perform all these actions for a reasonable price. The primary premise being a computer is available.
  • With the equipment listed in this project, this computer can record shows or movies from wither the cable feed or from VCR tape, save recordings to the hard drive for storage, and burn DVDs from stored footage (personal use only), send video to the monitor for watching, record footage from any RCA source (i.e. XM radio), and turn the computer into a television. NOTE: "Pirating" movies is illegal. Only personal use is allowed. Don't do stuff that is illegal in your area.
Equipment, beyond a basic computer used in this project:
  • An ATI "TV Wonder PRO" PCI TV capture card with S-Video Input and RCA Input compatible with nearly any VCR. ($30.00 w/rebate)
  • An NVIDIA MX440 AGP Video Card with 64 MB RAM and a S-Video TV Out port. ($20.00 used)
  • A Sony DRU-710A 16X +All Format DVD Recorder ($89.00 brand new). The DRU-720A is available at $89.95 as of 06/03/2005. The DVD burner can be used for data backups, restore DVDs, and other uses beyond this project of course.
  • A spare Coaxial cable (free from cable guy)
  • A Radio Shark...err Shack coaxial splitter ($3.00)
  • Total cost: $142.00
To do this project, it need to have access to a coaxial antenna. This could be a cable outlet (seen here), a satellite feed, or a standard "over the air" antenna that connects to the TV using a coaxial connector. You do not need to have "pay" TV, just an antenna with the coaxial connector.
Second, you may need a standard coaxial "splitter". The splitter divides the signals strength, or amplitude, into (usually) equal parts but maintains the information in the line (frequency). The splitter is needed if you only have one coaxially source but you need to send the signal to another device other than your computers TV tuner card. An example would be a cable modem.

Note that splitters will make an already weak signal even weaker. Probably half as strong. This has to be taken into account if you are using a cable modem and are having problems syncing up with the broadband companies node.
Third, you will need a TV tuner card for your computer. This component will be the heart of the DVR.

The card should have the ability to not only tune (decode) the TV signal but also send the resulting signal to the hard drive as digital information in a common format (ex.: MPEG2, MPEG4, AVI, etc.). Some cards can only receive and decode the TV signal but have no ability to record the show to a hard drive. These card should be avoided. They are perfectly fine for viewing TV on the PC but cannot be used to create a DVR.

Here an internal PCI TV tuner card is shown. This particular card cost $29.95 (after rebates, yikes) and is powered by a Phillips-Magnavox TV tuner with coaxial input connector. This card is distributed by ATI technologies under the marketing name "TV Wonder Pro".

The so-called "PRO" feature is the ability to record the TV to the hard drive rather than just show it to the computer monitor and the PRO has an input connector making recording from a VCR possible.

Other popular brands include Haughtpage and NVIDIA. Note that most manufacturers offer cards of various capabilities and price is not necessarily a good determinant of capability. Spending more money does not always get a better product. Make sure the card does every thing you need before buying.

Caveat: In my experience, ATI is excessively difficult to get rebates back from and they have had multiple complaints filed with the Better Business Bureau in 2005 for this reason. However, I still like their products from a technical point of view. Caveat Emptor!
The silver box attached to the card is the Phillips tuner. The black chip is the controller/integrator chip from ATI.
Here, the connector is (somewhat fuzzily) seen along side the input port and sound output port. The card decodes the sound from the TV signal and pipes it out the small port on the right. This is the sound output port.
You will need an open PCI slot for this type of card. You will also need to know how to install the card. Here, I evaluate the situation, and decide to place the card in the right most slot because the Advanced Graphics Port (AGP) is farthest from this position. Some tech folks claim this helps minimize collisions between the graphics card and the TV tuner card. In my experience, I have only had trouble when installing the TV tuner card on a machine that had an NVIDIA graphics AGP card with a VIA technologies North Bridge controller.

Legend has it that this is caused by a video loop problem that occurs on systems that have a VIA Northbridge controller chip, NVIDIA graphics accelerator, and an AMD CPU. NVIDIA and VIA have taken turns pointing fingers at each other but I know of no repair outside of hacking the BIOS (Turn off the RX55 register). This machine here has a Pentium 4 CPU so it does not fall into said category.
While upgrading the machine, I chose to remove the existing 32 MB video card in exchange for this NVIDIA 64 MB MX440 AGP card. The MX440 is an older model and can be had very inexpensively. This particular MX440 was chosen because it has an S-Video output port so I can send the recoded shows to my TV's S-Video input port. This will allow me to watch the recorded shows on a regular TV rather than just the computers monitor. Additionally, the MX440's higher processing power and onboard memory make it a better playback choice. Finally, it is worth mentioning again that these great performers are now inexpensive due to far more powerful cards being on the market. This card was acquired "used" for $20.00.
The MX440 used has a standard video output port for an analog computer monitor and an S-Video output port for transmission to a TV, VCR, DVD recorder, amplifier, etc.
Now we have the TV tuner card in the last PCI slot and the MX440 video card in the only AGP slot. Once the computer is buttoned up, we install the TV tuner drivers, then the TV tuner recording software bundle. Each tuner cards software bundle is unique and proprietary. The basic features to look for are the ability to schedule shows, record in multiple formats, and play back recorded shows.
As mentioned, the ATI TV tuner has a sound output port and a proprietary input port that uses a provided cable. The "PRO" card comes with a sound cable and a multi-input video cable.

The purple multi-input video cable here has S-Video input, along with right and left sound channels. This allows a VCR or other video source to be sent into the tuner card as both video and stereo sound.  Having the input connector is useful for transferring VCR tapes to DVD. To create DVDs, you will still need a DVD burner or access to a computer that has one. This computer does not have a burner but is on a network with another computer that has a Sony DRU-710A 16X burner. Making DVDs is easily done after recording the VCR tape by setting the cards input from "external antenna" to "input cable source" and recording to the hard drive. One digitized, the video can be transferred and burned at a later time.

The small black cable is the sound card cable. The sound cable simply transfers sound from the TV tuner card to the computers sound card via the sound card input port.

A close-up reveals the input ports positions and the special purple multi input cable provided by ATI.
Some more advanced video card come with adapters that can output the shows  recorded by the tuner using various methods. Here an NVIDIA adapter outputs the video as Component and S-Video. This allows the video card output to be sent to devices that receive input in various ways. For example, some TVs use S-Video for input while others use composite video/sound cables.

At this point, all software for your card needs to be installed. Test that the card can display TV on the monitor first, then try recording a short piece. The most common problems will be driver issues but most cards will run reasonably easily on Windows XP. Linux is the hardest to get running die to poor support by manufacturers of the cards. Perhaps Haughtpage is the best choice for Linux.