All posts by Briantist
Below are all of Briantist's postings, with the most recent are at the bottom of the page.
murgatroyd: OK, I have done that .. see Map of all DAB transmitters | ukfree.tv - 11 years of independent, free digital TV advice for example.
| link to this comment |
Kieron Quinn: It doesn't look like Real Radio is on any local radio multiplex, at least yet.
Details of REAL RADIO DAB radio station | ukfree.tv - 11 years of independent, free digital TV advice
| link to this comment |
michael: http://stakeholders.ofcom….pdf defintions for FM
For DAB, see http://stakeholders.ofcom….pdf - which states "The revised planning criteria for indoor coverage, described in Section 1.2, seem appropriate in the light of the review of building loss measurements (section 2.7) and the receiver performance measurements (section 2.4)."
1.2 UK planning limits
DAB planning parameters are set out in the Ofcom document Technical Policy Guidance for DAB Multiplex Licensees [Ofcom, 2006].
This document notes that new DAB transmitters (i) must avoid causing interference to existing, co-channel, services (ii) should not serve overspill zones beyond the licensed coverage area and (iii) should not cause interference to DAB services in the same area.
The last requirement relates to the need to avoid hole-punching to existing networks due to the use of non-co-sited transmissions. Such transmissions will, inevitably, cause the necessary protection ratios to be infringed for some area
around the new site. There is, therefore, a strong incentive to co-ordinate transmitter sites where possible, and this is formalised through the Reserved Assignment List. This list, drawn up collaboratively by multiplex and transmission
operators and Ofcom, identifies locations that are likely to be useful for DAB coverage and (i) requires use of the site to be on a non-exclusive basis and (ii) makes explicit to all operators that any other licensees in the area may be expected
to use the site at any time.
The technical planning standards are set out in Section 5 of the Ofcom document, and are specified in terms of the median field strength at 10 m above ground, with predictions made to the centroids of 100 m x 100 m squares. Two thresholds are
used:
58 dB(V/m) [a mobile listening environment, and above a first floor level indoors, on typical portable receivers]
65 dB(V/m) [indoor reception, in the majority of domestic buildings].
Within the licensed area, a protection ratio of 25 dB is to be ensured for 99% of time. The document notes that this is based on calculation, supported by field trial data gathered in 1997 by Ofcoms predecessor, The Radio Authority).
Revised planning criteria are currently being developed. These leave unchanged the 58 dBV/m figure for mobile coverage, but give four criteria for indoor coverage. In dense urban areas useful coverage is defined to be provided for a 10 m field
strength of 71 dBV/m and robust coverage at 77 dBV/m. In other areas, the corresponding limits are 64 dBV/m and 70 dBV/m.
| link to this comment |
murgatroyd: Thanks for pointing out what needed to be done.
There is little point providing maps if they don't convey information to make them useful.
| link to this comment |
michael: I'm interested in your comment
"DTT mis-planning resulted in CCI which Ofcom would neither recognise nor rectify"
could you be more specific please?
| link to this comment |
Scott Andrews: Oh. Eutelsat 28A & Astra 1N/2A/2F at 28.2°E - LyngSat says STV HD is on it too.
| link to this comment |
Brian Wright: It was a reasoned choice that was taken by all those involved.
There were arguments on both sides, as you outline, and the decision was taken as I have said.
What was important was that a decision was made, so everyone knows where they stand.
It's not "madness", it is quite, quite rational.
| link to this comment |
Mark A.: The Ofcom/Arqiva documents didn't have lat-long or national grid locations, so for new DAB transmitters , I had to:
1. See if there was an UHF transmitter;
2. Then see if there was a VHF transmitter;
3. See if there was a mobile phone mast
.matching the description. Those that still remain were copied as best I could from the blurry maps in the PDFs.
| link to this comment |
Thursday 12 September 2013 5:11PM
Kieron Quinn: Please see Four regional DAB multiplexes to close in 2013 to allow for better local DAB | Digital radio | ukfree.tv - 11 years of independent, free digital TV advice - 12C/North West DAB multiplex closes on 24 September 2013.