On 05/10/2023 22:46, JMB99 wrote:
> On 05/10/2023 22:43, Brian Gregory wrote:
>> Not having to radiate any sidebands would save power.
>
>
> Rather defeats the object of broadcasting if you do not transmit any
> modulation?

Try reading the _whole_ of this thread

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Mark
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Brian Gregory <void-invalid-dead-dontuse@email.invalid> wrote:

> Ever seen an AM signal on a spectrum analyser?
>
> As the modulation varies in strength the strength of the sidebands
> increases and decreases with the loudness of the modulation while the
> strength of the carrier stays constant.
>
> Not having to radiate any sidebands would save power.

I think we are all agreed on that. My comment was that the additional
losses of an A.M. modulator, which was no longer required for
modulating, could also be avoided by switching it off entirely.

Actually some stations do reduce the carrier power on heavy modulation,
I have seen it on actual broadcast signals using an Eddystone Panoramic
Adaptor. I don't know how they do it without causing all sorts of
distortion problems, but I suppose a bit of distortion on shortwave
signals might be considered worth the power savings it could bring.

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~ Liz Tuddenham ~
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On Thu, 5 Oct 2023 22:48:50 +0100, Brian Gregory
<void-invalid-dead-dontuse@email.invalid> wrote:

>On 05/10/2023 22:01, Scott wrote:
>> As I pointed out, some of the Pure radios could be upgraded by
>> software. I think it cost AUD 10.
>
>Australian dollars??

Yes, I saw it at the time Australia was moving to DAB+.

On 05/10/2023 19:57, Scott wrote:
> Am I not correct then that there must be very few DAB (no DAB+) radios
> in use and therefore little to prevent the BBC switching? Is there any
> cost or is it simply a case of resetting the coders?

Well we have a DAB radio about 16 years old in use every day which doesn't do DAB+. Since it has a record to SD card function that I can't find on any more modern radio, I'd be loth to give it up. There are already quite a few stations that come up on its programme guide that it can't actually receive, but provided the BBC stations stay in DAB non-plus that's ok.

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Clive Page