Understanding HD television reception on my PC

What is HDTV?

First, let's explain the concept of HDTV. HDTV broadcasts are available in higher resolution than standard analog television. HDTV is typically 720p to 1080i resolution, where standard definition analog resolution is broadcast at 480i. The number 480 refers to 480 lines of resolution, while the 720 and 1080 refer to 720 and 1080 lines of resolution in the HD TV broadcasts. The more lines per TV image, the better the television image quality.

In addition to more lines per TV image, HD television also has more dots per line (called 'pixels'). The more dots per line, the better the television image. Standard definition television has 640 dots per line (or 640 pixels per line) while 1080i has 1920 dots per line. So you can see, HD television has both more dots per line and more lines per TV image.

Because of the larger number of dots per line and more lines for each TV image, HDTV broadcasts offer much more clarity for a sharper, clearer television image.

The little 'i' in 1080i refers to 'interlaced'. Interlaced video, as used in the 1080i format, is good for HD movies but not as good for HD sports programs since interlaced video tends to blur with fast motion. Blu-ray DVD disks use 1080p as their standard HD format.

ATSC vs. Clear QAM vs. HDTV from my cable or satellite box

There are a few different broadcast standards for HDTV in North America. Here are the differences.

ATSC: ATSC broadcasts are over-the-air (also called 'terrestrial') HD digital TV. ATSC is the new TV standard for over-the-air TV broadcasts. If you live in the U.S., you are familiar with the TV commercials which were run by the FCC in June of 2009 alerting U.S. residents to the switch over to HD TV. The FCC was referring to ATSC TV, which is the new digital TV standard for North America.

The highest definition format for ATSC is 1080i. But many ATSC broadcasters transmit lower resolution TV, as low as 480i. Prime time sports programs, such as the Superbowl and the Olympics, are broadcast in 720P since this format is better for fast moving sport events.

If you are using a roof top antenna or rabbit ears and you live in the U.S., after June 2009 you can no longer receive analog TV broadcasts. Instead, you will get ATSC over-the-air HD TV broadcasts (as long as you are using an HDTV ready TV tuner such as one of the Hauppauge WinTV-HVR series of products).

Clear QAM: Clear QAM TV are free HDTV channels transmitted by cable companies. These are typically limited to local broadcasts only, (re-broadcasted ATSC channels.) Sometimes cable providers may pass some other channels in the clear as well, however you will not receive any premium or 'pay' channels with clear QAM. In general, the highest definition clear QAM channels are 1080i.

HDTV with a set top box: If you are using a cable TV or satellite TV set top box, you can watch and record TV from the set top box by using the 'auxiliary A/V inputs' on most WinTV-HVR products. When you connect a set top box to a WinTV product, you can watch all of the TV channels that are decoded by your cable or satellite set top box. When you connect your set top box using 'auxiliary A/V inputs' on the WinTV, the image you will receive will be in standard definition.

When you connect a set top box to the Hauppauge HD PVR, you will use the Component video output (YPbPr, which are colored red, green and blue) from your cable or satellite set top box. In this case, the TV format recorded will be HD, up to 1080i.

Example using the WinTV-HVR-1850 PCIe Board:


Analog TV (+FM radio) Coaxial input: You can connect your existing cable TV to this input to watch analog cable TV channels. The WinTV-HVR-1850 model also supports FM, so by connecting an FM antenna instead, you can listen toFM radio on your PC with Windows Media Center or the Hauppauge WinTV v7 application.

You can also connect the coaxial (RF) output from your cable or satellite set top box to this input. When you connect to your set top box through this connector, you will normally tune to channel 3 in the WinTV program to see TV from your set top box. Note: The broadcasts will be in viewed and recorded in standard definition.

Digital TV/ATSC/QAM Coaxial input: You may connect digital cable TV to this input to tune your digital QAM channels, or you may connect an antenna to this input to tune ATSC channels. All of the channels on this input will be digital and displayed and recorded in the native format of the broadcast (from standard definition up to 1080i).

A/V inputs: For the WinTV-HVR-1850, there are options for S-Video and composite (yellow RCA jack) video inputs. You can connect the S-Video or composite video output from your cable TV or satellite set top box to the A/V inputs. The video formats for both composite and S-Video are standard definition, though the video quality is higher than if you were to connect via the Analog coax input.

You will need to also connect audio from your set tio box to the 1/8” stereo line input for sound. The audio output from most set top boxes are RCA (red and white), and would require an adapter to convert them to one 1/8” stereo input. Other video sources such as external DVD players, game consoles, VCR’s, and video cameras may also be connected using this method.

Example using the Hauppauge HD PVR:


To record HD from a cable TV or satellite set top box, you can use the HD PVR. The HD PVR is normally connected to the Component video outputs of the set top box. The HD PVR does not have a built-in TV tuner, so you cannot connect it directly to an ATSC antenna or clear QAM coax cable TV. It can only be connected through a set top box.

Any programs which you can watch on your cable TV or satellite set top box can be recorded in the original format onto your PC with the HD PVR. The maximum resolution of your recordings on HD PVR is 1080i. Note: you can also connect to a PS3 or Xbox360 to record your game play.

Component video input: To connect HD PVR to a set top box, you will normally use the Component video output of the set top box. Component video from a cable TV or satellite set top box is normally 1080i maximum resolution. Note: the HD PVR also has S-Video and Composite video inputs, which can be found on the front of the HD PVR box.

Stereo audio input: is Left/Right stereo audio and is recorded as the audio part of your TV recording.

Optical audio input: Optical audio out is often found on cable TV and satellite TV set top boxes. Optical audo can be either 2 or 5.1 channel audio. This is a digital audio stream which can be recorded as part of your TV recording.