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Message: <blockquote data-quote="Fisty McB" data-source="post: 1157694" data-attributes="member: 389824">Almost certainly cost - the UK spot beam transponders (or rather, the transponders that can transmit on the UK spot beams) are rumoured to be among the most expensive above the European skies, and with the exception of the 12.5-12.75 GHz band, all capacity at 28E is intended for DTH use, at least in Europe. OTOH a service like Satback which is not intended for DTH reception can use a satellite where larger dishes can be used at TX sites to compensate potentially for lower transmission powers from the satellite used, and thus use cheaper satellite capacity.In addition, using Satback from Astra 2x would probably require more than one transponder - the current Satback transmission parameters gives a net data rate of 78.88 Mbps. Satback needs a minimum data capacity of 64.36 Mbps to carry the data of the two DTT multiplexes that it carries. Also, the in-use Astra 2x transponders are relatively narrow and are unlikely to be able to carry the 44100 symbol rate Satback uses at 27.5W. Some rough calculation would suggest needing to use at least 16APSK modulation to match or increase the 78.88 Mbps data capacity on an Astra 2x transponder.In the meantime, the Freesat "home" transponder on 11426 H is being used for national DAB feeds at transmitter sites for the BBC, D1 & SDN ensembles as there's enough spare capacity on there to carry them, and why let it otherwise go to waste! The duplicates at 9E will probably go away at some point in the future. Just not enough capacity (or indeed anywhere near it) for Satback.Finally, as it is, hobbyists like ourselves have to accept that things like Satback will always be in a state of flux, and that is a hazard of the hobby - not much like this is permanent, same applies for other multistream & T2-MI feeds done via satellite to terrestrial TXs elsewhere. Trying to find a crumb of comfort in thinking that Satback won't eventually finish on 27.5W is a bit like some on here a few years back when Eutelsat 5 West B was found to be having malfunctioning problems that meant it could only ever be used at half of the maximum capacity, thinking that it would prolong 5 West A's mission - 5WA was already on its last legs by the time 5WB reached its final position, and no amount of wishing prevented 5WB eventually entering service with the corresponding reduced footprint for many compared to 5WA. IS901-MEV1 will eventually run its course at some point, next year at the latest, and Intelsat have made no public plans of a replacement bird at this position. C'est la vie.</blockquote>

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