Questions tagged [spectrum-analyzer]
Questions about the use and theory of spectrum analyzers. For spectrum displays that are not test equipment, use [panadapter-and-waterfall] instead.
22
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Is the noisy spectrum from 20MHz to 330 MHz normal?
I have recently been testing some VHF/UHF antennas for reception in my Lab, and have noted something I could not explain. Following are the spectrum plots captured on our R&S FSV spectrum analyzer,...
- 23
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votes
1
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Why would a VNA not make a good Spectrum Analyzer? Or an SDR a good VNA?
Happy to be corrected where I'm wrong in any of this but in broad strokes my understanding is:
Spectrum Analyzer
measures input signal strength while sweeping across frequencies, measuring RF ...
- 7,421
-2
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1
answer
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How to know whether aliasing occurs when observe unknown signal?
Per my good but downvote question,I am hard to set sample rate even to a standard cosine wave.
When I observe unkwon signal,how to judge whether aliasing occurs?
- 650
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answer
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Why is 9 kHz the lowest frequency for spectrum analyzers?
I researched a number of spectrum analyzers and it seems that the lowest frequency that these operate at is 9 kHz.
Why is the lowest frequency supported by spectrum analyzers 9 kHz?
- 650
-1
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1
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91
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What's the negative float of rtl_power output means?
I got below float numbers after soapy_power -f 80M:100M -B 1000 --output a --format rtl_power:
...
- 650
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1
answer
82
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0
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1
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181
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Why so high values of noise température of a spectrum analyser?
We know that the displayed average noise level(DANL) and noise figure(NF) of a spectrum analyser is given by the following equation:
\begin{equation}
NF_{𝑆𝐴} = 𝐿_{𝐷𝐴𝑁L}[dBm] + 174dBm −10 \cdot ...
- 165
7
votes
3
answers
832
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What cause the spectrum peak of `center frequency`?
I use gnuradio and fosphor to view the spectrum from USRP B210, default gain set to 34, output looks like concave as below:
...
- 650
2
votes
1
answer
222
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How the ELF-VLF background noise spectrum looks like?
In the ELF-VLF frequency band,some background noise like Schumann resonances shows in the spectrum analyzer as peaks.
I want to have a overview look of the background noise of ELF-VLF frequency band,...
- 650
3
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3
answers
3k
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How to increase the range of the spectrum analyzer in SDRSharp?
I'm trying to visualize the frequency band utilization during a GSM phone call using SDR. Ideally, I would like to plot the whole 900 MHz range, i.e. 876-959 MHz. However, even setting the zoom to the ...
- 133
2
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0
answers
178
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Is this signal BFSK or BPSK?
I'm trying to analyse a signal from a HVAC remote control (864 MHz) with my HackRF, but I'm facing an interrogation about the used modulation:
Is it BFSK (frequency modulation) or BPSK (phase ...
- 21
1
vote
1
answer
320
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Looking for a convenient audio frequency spectrum analyzer
I would like to have a convenient tool to measure filters and amplifiers in 20 Hz - 20 kHz frequency range. Currently I'm doing this with a signal generator, an oscilloscope and LibreOffice. It's not ...
0
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1
answer
288
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What determines the bandwidth of an FM signal?
With an FM signal, it takes up more room in the radio spectrum presumedly because the carrier frequency is changed. On average what's the width of the FM sidebands?
Does the deviation from the center ...
- 7,421
0
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1
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312
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Most accurate way to measure signal power with (cheap) Spectrum Analyzer
I am using an USRP X310 which is unfortunately not calibrated and the specs given are only very vague.
Hence I would want characterize the device with first-order measurements. Unfortunately I only ...
- 163
1
vote
1
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496
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Retuning 2m Duplexers (Q2330E) with Spectrum Analyzer and Tracking Generator
Yesterday I was trying to tune up the duplexers one can at a time as listed in this Sinclair Youtube Video.
After tuning them my receive is awful and my transmit is somewhat not what it used to be. ...
