[mythtv-users] Picking the best signal strength (DVB-T and DVB-T2, UK)

[John Pilkington]

On 04/12/11 12:04, Keith Edmunds wrote:
> Hi List
>
> Background: I'm in the UK, Forest of Dean, nearest transmitter Ridge Hill
> (about 21.5Km away).
>
> If I carry out a scan, I get the usual unique and duplicate channels
> found, and I add them all. I will then find that I have, for example, two
> "BBC HD" channels. I suspect they are from different transmitters, but how
> can I tell which is the strongest signal?
>
> What I used to do: I used to edit the dtv_multiplex table and remove all
> the entries with frequencies that were not listed at
> http://www.ukfree.tv/txdetail.php?a=SO630333 (ie, those from Ridge Hill).
> I'd then remove any entries in the channel table that referred to the
> now-deleted mplexid entries.
>
> I've recently added an HD receiver (PCTV Nanostick 290e). According to
> the URL above, the Ridge Hill transmitter uses 482.2MHz for the mux with
> the HD channels on. However, I find that a) I have two entries for each for
> the four HD channels and b) the dtv_multiplex table doesn't include the
> frequency 482.2MHz.
>
> So I'm confused. I think what I want is to only receive stations from the
> Ridge Hill transmitter, but I don't understand why the HD mux frequency
> isn't in the dtv_multiplex table.
>
> Bottom line: what's the best way to ensure that each and every channel is
> being received from only the strongest signal?
>
> Thanks for any help.

Unless you have a good directive aerial pointing to a suitable 
transmitter there's no guarantee that the best signal for one multiplex 
will be the best for all, but given that, I suggest you delete all 
channels and all but one transport that you know comes from the best 
transmitter;  I've used the bbc SD mux as a starting point.  Then rescan 
with the 'link transports' option enabled.  You may need to scan more 
than once.  I think the dvb-t2 mux should show up then, so you should 
end up with six transports and no duplicate channels - but I think your 
region has more transmitter options than mine so ymmv.

HTH

John P