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On Sat, Jul 08, 2006 at 12:43:01PM +0100, Rob Beard wrote:
> Thats what I thought. It works ok with out Freeview box although we
> can't get Channel 5. The ariel is not a proper digital ariel so I guess
> that doesn't help.
There's no such thing.
Digital and Analog TV are broadcast on the UHF spectrum, in 8MHz
channels, from channel "21" to "68" inclusive. BBC1 Analog might be on
24, ITV on 27, for example. BBC Mux 1 might be on channel 41, Mux B (the
second BBC one) on 22, etc. etc. The reason it's so spread out is due to
interference with neighbouring regions (and countries).
Normally channels aren't broadcast next to each other, although
ocassionally Digital will be interleaved with Analog.
If you get Five on analog, chances are it's arround channel 36, there
were problems when it launched as many VCR's used UHF36 to output their
signal. To add complications, many people get "Five" from a different
transmitter to normal TV.
Nethertheless, most areas of the country has analog TV clustered in the
same portion of the UHF spectrum. Channel 21 - 36 for example. This
means many aeriels are in certain "groups", which provide high
gain/pound for certain UHF channels.
When digital started, it wasn't always possible to broadcast the 6 DTT
channels in this range. As such, while your aerial might get a great
picture for BBC1 on UHF23, it might not for Mux A on UHF56.
A "digital" aeriel is a wideband aeriel, which gives a good gain
across the UHF spectrum. They may sometimes give a lower gain on some
channels than a "Grouped" aerial.
The fact you can pick up two MUXes fine, but not the rest, leads me to
believe that your local transmitter broadcasts something like
BBC1 UHF56
MUX1 UHF57
BBC2 UHF58
ITV UHF62
C4 UHF60
MUXB (BBC) UHF62
MUX2 UHF28
MUXA UHF30
MUXC UHF34
MUXD UHF40
As such, a wideband ("digital") ariel should mean you'll get the full
complement of channels (all DTT enabled transmitters broadcast all
muxes, I believe, and I'm fairly sure at the same power too)
Depending on cost, have a word with a reputable arial installer and ask
about it.
(And no, I can't spell aeriel/arial/ariel/aerial!)
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