Analog TV cards

With analog television, the picture and sound information to be transmitted is prepared according to a modulation process and forwarded on in wave form in a medium such as air or via a cable. This requires an analog TV card with analog antenna input.

Digital TV cards

A digital TV card is required to receive digital programmes via the PC. The signal is transmitted according to the standard for the compression of TV signals, MPEG-2 (Motion Pictures Experts Group, 2nd standard).

The digital technology packs the data as binary code in data packets which are then decoded again by the receiver. This decoding is carried out by the DVB card in the PC.

There are three options for receiving digital television

−DVB-C (Digital Video Broadcast-Cable) reception via cable

−DVB-T (Digital Video Broadcast-Terrestrial) reception via antenna

−DVB-S (Digital Video Broadcast-Satellite) reception via satellite

The reception quality is much better with DVB cards. As the digital programmes are transmitted in MPEG-2 format, the TV programme can also be processed directly on your PC hard disk.

A further difference is in the decoding of the MPEG stream. Differentiation is made between TV cards with hardware MPEG and TV cards with software MPEG.

•With hardware MPEG, the processing power is undertaken by a chip on the TV card. This means that there is practically no involvement of the PC’s CPU. The majority of the CPU’s processing power remains available for other applications.

•With software MPEG, the CPU is responsible for the processing power. Under some circumstances this may lead to the CPU being noticeably overloaded.

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