This much is correct.
Total rubbish. In a marginal area a GOOD low noise amplifier at the Antenna will give better reception as with any other form of transmission system. It must have a very low noise figure and enough gain to make up for any feedline loss and splitter losses between the antenna and the receiver. Lots of gain is not better but an amplifier can make an otherwise unreceivable signal watchable. There is a requirement that there be a carrier to noise ratio of at least 19+ dB at the antenna to receive DVB COFDM transmissions with a 23Mb/s data rate.
bassett also wrote....
This is the most hysterically funny explanation of how digital works that I have ever seen. It just proves how clueless bassett is about things digital.
Firstly there are not 4 layers of anything transmitted. The transmitted signal used for terrestrial transmission in Australian standard digital consists of either 2K (some 1700 carriers) or 8K (some 6000 carriers) in quadrature each modulated with 64 QAM (Quadrature Amplitude Modulation) giving a stream data rate of 23.052768 Mbits/S with our normal FEC and guard interval. The use of FEC is a method of transmitting extra bits with the wanted stream MPEG data to make it more rugged. The FEC is not in the receiver it's transmitted as extra data bits in the stream that allow reconstruction of damaged packets in the receiver. What 3/4 FEC means is that for every 3 actual bits of data an extra bit is transmitted as FEC. In other words for every wanted 3 bits of information
4 are transmitted. NOT 4 signals only one with extra information.Small corruptions of the stream data will not cause pixellation as the FEC allows the damage to the data to be corrected and no visible degradation is seen. If the data is corrupted more than the FEC being transmitted is capable of correcting then either pixellation will occur or the decoding will fail.
If high values of FEC are transmitted such as 1/2 where every bit in the stream is transmitted twice there is obviously more correction available but at the penalty of loss of wanted data rate.
In particular on satellite transmissions FEC values of 1/2, 2/3 or 3/4 are usually used especially 1/2 or 2/3 where small dishes are being used for reception.
The more robust forms of FEC are not generally used in terrestrial digital transmissions as there is a need for the highest possible data rate to be able to transmit HD and SD at once in the same stream.