The VP305/6 is a decoder for digital satellite television transmissions to the European Broadcast Union ETS 300 421 specification (ref. 1). They receive digitised I and Q signals from the tuner, demodulate the QPSK data and provide a complete Forward Error Correction, (FEC) and descrambling function. The output is in the form of packetised MPEG2 transport stream data. The VP305/6 also provides automatic gain control and synchronising signals to the RF front end devices.