Local TV

5,000W.... Its bad enough due to the hills around Edinburgh 1/3 of the locals will not be able to get the Craigkelly but the fact even more people will not be able to view it due to a reduced wattage is beyond a joke.

Who on earth do there expect to watch this channel or even the two ( soon to be four) other four channels on the freq?

People who actually live in Edinburgh, mostly.

Yes, it is only 5kW, but what the UK Free website fails to explain, is that it's QPSK modulation, that is a more robust form of modulation than 64QAM used for the other (SD DVB-T1) muxes. Everything else being equal,
5kW QSPK , would easily match (I'd say probably exceed) the coverage of the 10 and 20 kW 64QAM muxes (Although that's not to say the local mux has different directional radiation characteristics)

Yep - but the Local TV mux is broadcasting using a different modulation system. Local TV muxes in the UK use QPSK not 64QAM (which is used by the other SD muxes on Freeview) to compensate for the lower power.

QPSK is far more robust than 64QAM and thus for a given broadcast power will 'go further'. This is the trade-off for the mux carrying a far lower bit rate. The Local TV mux carries 8Mbs, in comparison to the PSB SD muxes carrying 24Mbs (3 times as much) and the COM SD muxes carrying even more (as they use less error correction than the PSBs)

Each symbol in QPSK carries 2 bits, whereas in 64QAM each symbol carries 6 bits, so a QPSK symbol carries 1/3rd the information of a 64QAM symbol, and both system are using roughly the same symbol rate (and the PSB and LTV muxes use the same amount of Forward Error Correction).

In other words you only have to be able to detect 4 different symbol states for QPSK, but 64 different states for 64QAM, which requires greater signal to noise, and thus a higher received signal power etc. for clean decoding.

Try another brand - they're all the same, just a different box
("aerial" not "ariel")

I think in some cases the Local TV mux radiates in a different pattern (you can, to a degree, tailor the directions in which an aerial broadcasts) to the other muxes, so you can't always judge based on reception of existing channels.

Indeed. According to Ofcom data, the L-MUX antenna at Craigkelly, is 65 metres above ground level, the
antenna for the main six national muxes, is at 130 metres. No info available on directional characteristics,
that might require an FoI request, because the broadcasters don't seem to want that in the public domain

However, the data does drive the Digital UK postcode checker, what do you get sticking your details into that ? (Remember to tick 'Detailed View')

http://www.digitaluk.co.uk/

Are receivers all QPSK compatible?

They're supposed to be, but we all know about so called 'compatibility' from some manufacturers
ever since the UK DTT platform, went 'into the wild' in 2002.

This would explain why I was told to contact "Bush" The maker of my small telly I use for freeview.

There still one problem, 1/3 of people in Edinburgh cant get Craigkelly, thus wont get this new channel either. When is Blackhall getting the channel to cover this problem.

That's not a problem unique to Edinburgh. The majority of people in Sheffield don't receive their signal from the Crosspool mast that broadcasts the local mux. While there are plans to built a new transmitter in line with Emley Moor which a significant number of people do receive from, this will only affect a similarly small number of people - there's no chance of everyone in the city being able to pick up the new mux.

(not that they're missing out)