Zitat

Originally posted by npumcrisz
May be the first question is, does dvb-c work in USA.

The digital cable system used in the US is related to DVB-C, but I don’t think it is quite the same. For example, the US documents always seem to mention only 64-QAM and 256-QAM as the two possible modulation parameters for cable tv transmissions, but the DVB-C standard specifies 16-QAM, 32-QAM, and 128-QAM as well.

• The DVB-C standard is defined in ETSI EN 300 429 (“Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for cable systems”)
• The US digital cable standard is defined in ANSI/SCTE 07 2006 (“Digital Transmission Standard For Cable Television”)

Curiously, the Wikipedia page about the US system (see the first link in this message) mentions that it is “part of the DVB standard”. Go figure. This document might (or might not) explain the differences better:

• NCSC Digital Cable Report

Also see the comments by “CityK” on this page. I’d say it’s all clear as mud, but it is probably sufficiently safe to say that the US cable standard(s) is(/are) not compatible with DVB-C.

The question then becomes would it be possible to support the US cable standards on the DM 7025 hardware, given a compatible tuner module?

Theoretically speaking, yes, but the contents of the transmitted MPEG-2 transport stream metadata (service lists, etc.) are likely to be in a different format. Hence, the underlying logic related to tuning, parsing service lists, EPG, closed captions, etc. in Enigma2 would need to be rewritten from scratch for the US system. Not impossible, but a non-trivial amount of work.

The beaty of the DVB standards – as used in Europe and other parts of the world – lies in that the transport stream remains, logically speaking, pretty much identical regardless of whether you receive it from cable (DVB-C), antenna (DVB-T), or satellite (DVB-S). This common base between all DVB transmission methods is what allows the current modularity of the DM 7025. Once you add in support for a completely different system, or require a single device to support two different digital tv transmission standards at the same time – as would be the requirement for the DM 7025 – the implementation details get more hairy.