The point is, officially I shouldn't be getting SDN at all, for the following reasons.
1) SDN is not available on the Bath relay, therefore the SDN signal I'm now getting on UHF channel 48 must be coming from Mendip.
2) The aerial I use is
a) pointing at the Bath relay (wrong direction for Mendip).
b) vertically polarised (correct for Bath relay, but wrong polarity for Mendip).
c) about 10 elements (ideal for the Bath relay, but inadequate for Mendip where I live).
d) to the best of my knowledge, group A (wrong group for Mendip).
Despite all that, my Panasonic DVD recorder managed to store the SDN channels on UHF 48 last Wednesday morning following the modifications to Mendip. The signal quality for SDN on UHF channel 48 through that aerial is about 2½ to 5 out of 10. For comparison PSB1 (BBCA) on UHF 25 and PSB2 (D3&4) on UHF 28 come from Bath relay, and register signal quality of almost 10 out of 10.
My Panasonic DVD recorder tried repeatedly to lock on to UHF 52 (which at Mendip now carries ArqB), but was unable to store its channels.
B1 = BBC One B2 = BBC Two B3 = BBC Three B4 = BBC Four B5 = CBBC Channel B6 = CBeebies B7 = BBC News 24 B8 = BBC Parliament
I am 4 ... dozen