S meter Graph. How to enable S/N function?

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Rob PE1ITR

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Apr 22, 2020, 7:56:07 AM4/22/20
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Hi,

I would like to use the S/N function in the linrad S meter.
I am in linrad expert mode and can only toggle S, db, dbm and db/Hz.
How can I turn on S/N?

Using linrad 4.15.

73 Rob PE1ITR


Dominique DEHAYS

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Apr 22, 2020, 8:31:30 AM4/22/20
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Hi ,

 

there is no s/n mode , U have to measure S and N separately but U can normalize one of the measurements ( so choose your 0dB). It is a marvelous tool , I use it very often.

73

Dom

 

 

 

> Message du 22/04/20 13:56
> De : "Rob PE1ITR" <r...@itr-datanet.com>
> A : "Linrad" <lin...@googlegroups.com>
> Copie à :
> Objet : [Linrad] S meter Graph. How to enable S/N function?
--
There is an excellent Linrad User Guide by Gaetan, ON4KHG, at:
http://w3sz.com/Linrad%20Installation%20&%20Configuration%20User%20Guide%20-%20V1-0.pdf
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Rob PE1ITR

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Apr 22, 2020, 10:16:26 AM4/22/20
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Hi Dom,

There must be a convenient S/N function without having to calculate it yourself.

Press help in the S graph

"[91]Press left mouse button to toggle scale between db, dbm, S-units, db/Hz and S/N."
"[3]..There is also a mode to display S/N where S is from a narrow bandwidth as specified in the baseband graph while N is computed from the full bandwidth. The S/N mode is only available for expert users. .."


It is also showing on this page: http://www.sm5bsz.com/lir/nf/nf3.htm

73 Rob PE1ITR


Op woensdag 22 april 2020 14:31:30 UTC+2 schreef f6dro:

 

Hi ,

 

there is no s/n mode , U have to measure S and N separately but U can normalize one of the measurements ( so choose your 0dB). It is a marvelous tool , I use it very often.

73

Dom

 

 

 

> Message du 22/04/20 13:56
> De : "Rob PE1ITR" <r...@itr-datanet.com>
> A : "Linrad" <lin...@googlegroups.com>
> Copie à :
> Objet : [Linrad] S meter Graph. How to enable S/N function?
>
>
Hi,
>

>
I would like to use the S/N function in the linrad S meter.
>
I am in linrad expert mode and can only toggle S, db, dbm and db/Hz.
>
How can I turn on S/N?

>
Using linrad 4.15.

>
73 Rob PE1ITR
>

>

>

>

--
There is an excellent Linrad User Guide by Gaetan, ON4KHG, at:
http://w3sz.com/Linrad%20Installation%20&%20Configuration%20User%20Guide%20-%20V1-0.pdf
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f6dro

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Apr 22, 2020, 10:47:24 AM4/22/20
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Ok , sorry,   expert mode fonction,I'm not brave enougth to feel an expert on linrad
:0)




Envoyé depuis mon smartphone Samsung Galaxy.


-------- Message d'origine --------
De : Rob PE1ITR <r...@itr-datanet.com>
Date : 22/04/2020 16:16 (GMT+01:00)
Objet : Re: [Linrad] S meter Graph. How to enable S/N function?

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Leif Asbrink

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Apr 22, 2020, 11:48:26 AM4/22/20
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Hello Rob,

the S/N function uses the power from the second fft. You must
enable fft2 in order to get this mode.

The reason is that the power computation from the second fft
excludes those frequencies that are red in the main spectrum.
This is because we normally want to excluse spurs from S/N
measurements. In some cases it is meaningful to also eliminate
pulse noise in the S/N evaluation.

The signal is computed as the total power within the selected
baseband filter. The S/N ratio comes in an arbitrary scale
but since N is measured in a wide bandwidth and S in a very
narrow bandwidth one can do accurate measurements of S/N in
a short time.

73

Leif
> --
> There is an excellent Linrad User Guide by Gaetan, ON4KHG, at:
> http://w3sz.com/Linrad%20Installation%20&%20Configuration%20User%20Guide%20-%20V1-0.pdf
> ---
> You received this message because you are subscribed to the Google Groups "Linrad" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to linrad+un...@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/linrad/bb8d78b1-cfca-408b-836e-49382adcd8f3%40googlegroups.com.

Rob PE1ITR

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Apr 22, 2020, 3:12:47 PM4/22/20
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Hi Leif,

Thanks. I found it and it works now.

73 Rob

Op woensdag 22 april 2020 17:48:26 UTC+2 schreef SM5BSZ:
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