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Old 25th Oct 2017, 6:37 pm   #201
paulsherwin
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Default Re: Radio 4 198 sibilance

Back on topic please.
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Old 26th Oct 2017, 7:47 am   #202
Kevin Hoyland
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Default Re: Radio 4 198 sibilance

Radio 4 198 LW is back to being good today in South Yorkshire. Hope it stays like this.

Kevin.
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Old 29th Oct 2017, 3:32 pm   #203
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Default Re: Radio 4 198 sibilance

My latest report, without attenuator and with showing the RX isn't to blame, pretty terrible.
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Old 29th Oct 2017, 4:47 pm   #204
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Default Re: Radio 4 198 sibilance

It sounds OK to me at the moment but I wear hearing aids so not the best reporter.

There is a puzzle, I have checked the SDR’s at Southampton University and the one in the Netherlands. Both show clean signals of 10KHz width, wider than 9KHz channel width but it won’t cause any problems.

So why does your display show all the splatter, how far down above the peak carrier level is the splatter? I can’t see a scale on the vertical axis.

I am not criticising your results, just interested in the differences. It’s possible that the WebSDR software doesn’t display at a set level below the carrier, that could be an explanation.
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Old 30th Oct 2017, 9:18 am   #205
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Default Re: Radio 4 198 sibilance

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I can’t see a scale on the vertical axis.
No, it's 'out of shot' it is 10dB per division (voltage).

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Old 30th Oct 2017, 9:40 am   #206
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Default Re: Radio 4 198 sibilance

So we are looking at the spurious level 60dB down (voltage) over the carrier. I donít know but is this acceptable for 30 year old technology? Could it be better but the age of the components wonít allow it?

Listening at the moment it sounds ok to me, much less HF audio than either FM or DAB which is to be expected.

Edit. Just checked a WebSDR in Grimsby and the signal waterfall is very clean, all very interesting, I just donít know the answer, frustrating.
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Old 30th Oct 2017, 10:52 am   #207
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Default Re: Radio 4 198 sibilance

But they are only 35dB down on the sidebands, an audible amount.
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Old 30th Oct 2017, 10:59 am   #208
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Default Re: Radio 4 198 sibilance

I think the regs are based on the carrier not the sidebands but I could be wrong, I thought I saw a figure of -50dBc but this could relate to another frequency or modulation type.
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Old 30th Oct 2017, 11:43 am   #209
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Default Re: Radio 4 198 sibilance

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I think the regs are based on the carrier not the sidebands
And I think it is for harmonics only, spurious out of band emissions should be a lot lower.
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Old 30th Oct 2017, 2:38 pm   #210
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Default Re: Radio 4 198 sibilance

Outstanding good sound today, just been listening to the Archers on my Ekco A23, I wish it would permanently stay as clear and pleasant as this.
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Old 30th Oct 2017, 3:37 pm   #211
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Default Re: Radio 4 198 sibilance

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Originally Posted by merlinmaxwell View Post
And I think it is for harmonics only, spurious out of band emissions should be a lot lower.
Thatís fair enough, I donít know the regs, but does not explain the difference in the two designs of SDR unless you are using the same, then it gets more confusing.

The station sounds fine so unless there are complaints from the ITU or other stations I donít think much will be done.
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Old 5th Nov 2017, 12:19 pm   #212
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Default Re: Radio 4 198 sibilance

I noticed yesterday that on all the reports on the VHF-FM Radio 2 news transmissions, the intake of breaths between sentences were very evident, making the correspondents sound distinctly asthmatic.

Switching to the news on Radio 4, the intakes of breath on the same reports were very less noticeable, sounding much better.

Is this a normal 'artifact' in the different ways Radio 2 and Radio 4's audio responses are configured?

best regards ... Stef
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Old 5th Nov 2017, 3:43 pm   #213
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Default Re: Radio 4 198 sibilance

The audio processing settings are likely to be completely different. If you have only noticed this recently, it's possible that the R2 processors have been reconfigured.

Many stations use heavy processing of the studio mics to create a distinctive station sound, and the BBC is no exception.

Back to the topic of R4LW please.
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