Re: SDR-Console Power dBm Accuracy


jdow
 

Hm, of note the hot and cold noise source CAN become a problem during measurement. You must know both actual temperatures at the time of measurement. The assumed "290K" does not necessarily work. The old HP 340B had a noise head featuring a (gasp) actual 6AL5, empty state electronics, noise diode. It's filament power heated up the reference resistor above room temperature. So the meter COULD read out a negative noise figure. Boy howdy that weirded me out when it happened.

{^_-}

On 20210623 23:03:48, Simon Brown wrote:

Larry,

 

Relative values will be perfect, or at least as perfect as the ADC / tuner chip in the SDR. No doubt there’s a professional methodology which could be used, I’m not aware of this so wait to be informed.

 

Obviously there’s Windowing applied and with the Spectrum the optional smoothing.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Larry Dodd
Sent: 24 June 2021 01:53
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] SDR-Console Power dBm Accuracy

 

I have been asked the question, "How accurate are the SDR-Console dBm spectrograph and dBm meter readings?"  Can anyone answer that question? We are interested in measuring the noise floor of various SDR receivers.
Thanks,
Larry, K4LED


--
- + - + -
Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.

Join main@SDR-Radio.groups.io to automatically receive all group messages.