Set Top Box (STB) Basics

This page covers Set Top Box basics, often referred to as STB. A set top box is a digital device that sits between a dish antenna and a television set. It allows users to select different TV channels according to their preferences.

The dish antenna receives satellite signals, which contain various broadcast channels from providers around the world.

The set top box has a built-in tuning circuit that selects one channel from the received signals.

Set top boxes have many uses, including digital satellite receivers, digital cable receivers, digital terrestrial receivers, and digital IP TV. As shown in the figure below, next-generation set top boxes can be connected to many home devices/equipment such as tablets, PS3 play stations, laptops, TVs, and XBOX video game consoles.

The figure above depicts a typical set top box block diagram, which is self-explanatory. From this diagram, the following set top box specifications can be derived:

• Satellite input with a 75-ohm female connector
• Output video: 1 x RCA type
• Output audio: 2 x RCA type
• RF output: 75 Ohm male connector
• Supports DVB-S System compliant to EN 3000421
• QPSK modulation
• C/N ratio and symbol rate are compliant with the DVB-S standard
• Input level per carrier is about -65dBm (Min) and -25dBm (Max)
• Supports PAL-B for VHF and PAL-G for UHF in the modulation
• Supports RF output channel as VHF 3/4 OR Agile/UHF