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Questions tagged [spectrum-analyzer]

Spectrum analyzers display the amplitude of an input signal versus frequency. Typically the frequency extends along the X-axis and the amplitude extends up the Y-axis of the display. They are used to measure the spectrum of an unknown signal within the frequency range of the particular analyzer being used. Sometimes their name is prefixed by the broad frequency range they cover, hence terms such as Audio / RF / Optical spectrum analyzer.

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RF jammer module power measurement using a spectrum analyzer

I have an RF jammer module that works at 2390-2510 MHz. The voltage is 24-28 V and it can transmit up to 50 W. When I use a spectrum analyzer, the value is around -20 dBm. If I'm not mistaken, -20 ...
Raihan Anwar's user avatar
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Modifying TI schematic to learn more about amplifiers

Let me start off by saying that I'm a complete beginner. I've watched some videos on amplifiers and read about them but it's hard for me to analyze circuits that don't match exactly to the examples I ...
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Spectrum analyzer bandwidth and noise floor

I have a DUT to measure on a spectrum analyzer. The noise floor is -100 dbm. My signal has a bandwidth of 10mhz. I want to measure the amplitude of my signal and I measure the signal amplitude to be ...
user4434's user avatar
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Balun converting 100ohm single-ended trace to 50ohm single ended for spectrum analyzer

On my board, I have 100ohm differential pair traces connected to a 1:1 balun, so the signal impedance becomes 100ohm single ended. I would like to measure the signal spectrum with spectrum analyzer. ...
jsmith's user avatar
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How to calculate the maximum measure level on the spectrum analyser?

Suppose that all individual spectrum lines in the range from 1 MHz to 2 MHz have the same level of 40 dBuV. The distance between the spectrum lines is 35 kHz. Measurements were performed using a peak ...
HAPU's user avatar
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Confusion with spectrum analyser use

Considering broad range of spectrum analysers such as this one or this one. Are they just showing the FFT of a voltage signal? Here someone explaining the difference between the two and mentions: ...
cm64's user avatar
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How to make an 802.11b/g conducted power measurement, getting different results

I am an engineering co-op tasked with measuring the output power of an avionics WiFi unit. I want to measure the maximum conducted power at the coax port to then calculate max EIRP. The challenge is ...
Pxl's user avatar
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How do I calculate the THD of a given spectrum analyzer waveform?

The spectrum analyzer reference level is 0 dBm. The fundamental level is 3.16 dBm. The second harmonic value is -9.51 dBm. The third is -10 dBm. 4th is -19.89 dBm. 5th is -25.32 dBm. 6th is -23.46 dBm....
Hasalanka Nagahawaththa's user avatar
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2 answers
149 views

Measuring rise time with spectrum analyzer

Is it possible to measure the rise time (range 100ps-1ns) of a square wave signal with a spectrum analyzer (my oscilloscope has 100MHz bandwidth only)? My model is Rigol 3030N (9kHz-3GHz). My idea is ...
piotr's user avatar
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Data transfer between computer and Fieldfox N9917A using Python VXI-11 library

I accessed my Fieldfox device using the vx-11 library. But now I don't know which commands to access the data with. For example, with the CALC:FEED:MODE AVER command? I use Fieldfox programming guides ...
aycansgn's user avatar
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Keysight vs Tektronix: AWG+RT SigAn or VSG+RT Oscilloscope?

I'm evaluating some new RF hardware for one of my university's research labs, for antenna testing. We are between a Keysight vector signal generator and a real-time oscope versus a Tektronix AWG and a ...
kconway6's user avatar
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Spectrum Analyzer problem

I am seeing some strange behavior with my spectrum analyzer. It is a Tektronix RSA306B. I have put a 50 Ω termination at the input of the spectrum analyzer and I am seeing a lot of spurious ...
DRF's user avatar
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Power transmitted from Arbitrary Waveform Generator

I have an arbitrary waveform generator. The arbitrary waveform has 2x CW tones of same amplitude. I'm only able to configure the overall power of this waveform, and the generator's manual says this ...
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Calibrating the R&S FPL 1003 Spectrum Analyzer

I am setting up an EMC test bench and I have a spectrum analyzer(SA): The Rohde and Schwarz FPL 1003 Spectrum Analyzer. I am trying to conduct some preliminary tests to ensure that the results seen on ...
ORion's user avatar
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How can I separate differential mode and common mode noise of measured noise spectra on the line and neutral?

The following spectra are the measured EMI conducted noise by a switchable LISN. As this LISN has only one BNC output, the noise separator can not be used. The following spectra are of the noise on ...
WeTech's user avatar
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Converting \$\mathrm{V_{rms}/\sqrt{Hz}}\$ to \$\mathrm{A_{rms}/\sqrt{Hz}}\$ with an associate preamp gain

I connected my SR780 (spectrum analyzer, with PSD setting, y-axis = Vrms/√Hz to a pre-amp (DHPCA-100) in low noise mode/full bandwidth with different transimpedance gain settings (102 - 106 V/A) and ...
Oldrepublic's user avatar
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Reduce loading on opamp when connecting spectrum analyzer (tinySA)

I am trying to measure the spectrum of an output of a signal generator I am building. The output stage of the generator uses the AD826 op amp in differential amplifier configuration. The SA I use is ...
peter's user avatar
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Can I directly use an oscilloscope's FFT function for EMI measurement?

The latest oscilloscopes with FFT and real-time functions are very useful for EMI debugging with a near-field probe, but why can't we just use them for the far-field EMI scan? EMI receivers are much ...
David W's user avatar
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1 answer
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Is my spectrum analyser defective?

I recently acquired a DSA815-TG which comes with a tracking generator option. I currently don't have coax because I am in the process of ordering. So I decided to just use a thin 13 cm wire to connect ...
Dylan Muller's user avatar
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EMC pre-compliance test in the lab [closed]

I would like to test the EMI performance of our product in our lab. I have access to a small shield box, a spectrum analyzer. Should I test the device inside the shield box to isolate external noise? ...
Adnan's user avatar
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1 answer
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Is it ordinary that near-field probes do not detect EM noise?

Last week we did a pre-certification test with a device and it failed. Description of the device: It is powered from Li-ion battery. It integrates a BQ24090DGQT which is a Li-ion battery charger, the ...
JackOfHearts's user avatar
1 vote
1 answer
428 views

Signal Dimensions in Simulink

I'm using R2022a, in Simulink I can not find the Display tab to access Signals & Ports>Signal Dimensions. Could someone point me in the right direction please?. Also, in the figure below the ...
Kalamakra's user avatar
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Calibrating a VNA

I am using the Siglent SSA3032A-R spectrum analyser which has a Vector Network Analyser (VNA). Before measuring the impedance of an antenna under test so that I can match this antenna, I have to ...
MRB's user avatar
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What is the loss of the test antenna connected to the spectrum analyser?

I am testing the gain and radiation pattern of some PCB antennas and have a Siglent SSA-3032X-R spectrum analyser connected to a Tekbox Biconical TBMA1 measurement antenna. The test set up and antenna ...
MRB's user avatar
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7 votes
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Measuring signal with of nanosecond pulse width with a spectrum analyser?

I'm looking to measure the signal width of electronic signals (device under test, DUT). The problem is that these signals have a quite short pulse width which would require me to use a GHz ...
ulix's user avatar
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4 votes
1 answer
136 views

HP 8568B J1 Connector identification

Can anyone identify these 4 individual RF connectors? I think it's some sort of RP-SMB, but it could be something more foreign. I would need to buy 4 cables to connect up the spectrum analyzer. ...
Avid Coder's user avatar
1 vote
1 answer
3k views

Converting dB vs frequency to V/sqrt(Hz)/ frequency

I have taken noise data with a spectrum analyzer. Unfortunately, it doesn't seem able to plot the noise in the units of V/Sqrt(Hz) over frequency (Hz). What I have acquired instead is dB vs frequency. ...
Blackwidow's user avatar
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Approach to determine EMI frequencies in another factory

We produce AC-powered devices that connect to PC via USB. One of which was recently shipped to a factory (which is located in another country) in an environment with high enough EMI to make our device ...
Christianidis Vasilis's user avatar
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3 answers
244 views

Frequency converter for spectrum analysis

I have an oscilloscope/spectrum analyzer that has a maximum sampling frequency of 20MHz and I would like to analyze the spectrum of a higher frequency band (also 20MHz wide) for example 90-110MHZ to ...
zmaj zmajević's user avatar
2 votes
2 answers
329 views

Spectrum Analyzer Parameter Meaning

I have been working on an RF project and wanted to know the RF noise floor present in the lab. I connected the Lora Antenna to the spectrum analyzer as shown in the image below and set the Marker at ...
Adnan's user avatar
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3 votes
1 answer
705 views

What's the name of this spectrum analyser input connector (Agilent E4402B)?

Here's a photograph of the input connector and one of the attachments that came with it (which is this unknown connector to SMA converter).
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AGC circuit for a spectrum analyzer - seeking recomendations

I want to build a spectrum analyzer for my car stereo. 5 bands, left & right channels represented individually, 20 LEDS per band using cascading LM3915s per band and channel. (Yes, 20 LM3915s, 200 ...
Super-Dave's user avatar
1 vote
2 answers
3k views

How to estimate SNR on a spectrum analyser

In the picture, the spectrum analyser shows 1kHz has about -5dB and noise between -40dB and -60dB (I'll just pick a value somewhere in the middle, or -50dB). So the SNR according to the equation: $$ ...
KMC's user avatar
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1 answer
467 views

Passive Probe With Spectrum Analyzer

Is it possible to use a regular passive oscilloscope probe with a spectrum analyzer? If not, what are possible choices of probes to use?
Analog's user avatar
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2 votes
1 answer
290 views

Understanding RF spectrum of SMPS power supply

I have a (third-party) device that has failed EMI testing, and have been asked to investigate the cause and fix the issues. The device is an automobile accessory, and has 12 V DC power input. ...
LachlanI's user avatar
2 votes
1 answer
356 views

What causes the small peak at the start of the spectrum in a spectrum analyzer?

There is a "DC" peak that is at the start of the spectrum. I'm studying the differences between superheterodyne and FFT spectrum analyzers and I'm wondering if the peak is caused by the same ...
Leksi's user avatar
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1 answer
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Is there as way to verify a spectrum analyzer setup?

I just finished setting up my spectrum analyzer and I would like to ensure that everything is as accurate as possible. I was thinking of getting some kind of RF transmitter that transmits at a ...
Ih8th3c0ld's user avatar
2 votes
0 answers
39 views

how to determine max peak of switching regulator in frequency domain (radiated emission)

I want to know how do I determine what should be the switching regulator peak in frequency domain(Radiated emission) , and where should I measure (Output or on inductor , capacitor). Lets do below ...
Shahreza's user avatar
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1 vote
1 answer
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Plasma damage to body cells

Can exposure to plasma or energy from Tesla home windings damage the body's cells? More generally, will the plasma or energy from the Tesla coil ionize?
Merlin's user avatar
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Understanding Output From DFT

I should preface this by saying I'm a novice at all of this: I'm designing a system (using a stand-alone FPGA board combined with an ADC that offloads data to a GPU) that is supposed to look for high ...
bgodfrey's user avatar
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62 views

Real World Small Signal AC Analysis

As stated in this question: Antiresonance of multiple parallel decoupling capacitors: use same value or multiple values? I have been curious to the real-world effects of different capacitors and their ...
Kyle Hunter's user avatar
1 vote
2 answers
180 views

If I have a signal that switches between 5MHz and 4MHz faster than the sample rate of the ADC on a spectrum analyzer

Basically, what happens if your signal is switching between frequencies faster than the sample rate of the ADC in the spectrum analyzer? I have been curious as to what would happen in this case, would ...
electricSoul's user avatar
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188 views

Why does the peak power change with the spectrum analyzer's span?

Consider a continuous wave signal being displayed on a spectrum analyzer at f=5GHz. It's a single peak. When I put marker on the peak it shows me the peak measured power. Now when I decrease the span ...
hacker804's user avatar
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1 answer
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Characterizing a capacitor

I have a capacitor for which I would like to get the output impedance as a function of the frequency. I would like to get something like this: For this I have a spectrum analyzer with an output which ...
Jess's user avatar
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Workflow to test the quality of XLR microphone cables, and have a quantitative measure of this quality

I have more than 10 XLR microphone cables from different manufacturers (some of them quite cheap, some of them more expensive), and as I often do recordings (with condenser microphones) of music / ...
Basj's user avatar
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Spectrum intensity varies depending on the frequency span

I am trying to measure the noise of a photo detector at different frequencies, using an RF spectrum analyzer. The measurement range was spanning from 10 Hz to 20 MHz. To cover not only the higher ...
arc_lupus's user avatar
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1 vote
3 answers
225 views

Input Attenuation and Intermodulation Products

I am measuring intermodulation using spectrum analyzer. How does the input attenuation affect the power of intermodulation products?
annyyaa's user avatar
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0 answers
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Enhance sensivity of my magnetic field measuring setup

I have the following magnetic field measuring setup: Picoscope 2204A 16m wounded up bell wire connected to tip and ground clip as search coil antenna Now I want to enhance the sensivity for 50Hz to ...
Hansebenger's user avatar
1 vote
1 answer
339 views

DC filter for a spectrum analyser - cut off frequency

Most of the available spectrum snalysers do not want a DC component to their 50 ohm input. But how low should the cutoff frequency be? Also which parameters indicates that clearly in the datasheets? ...
Jeres's user avatar
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1 answer
380 views

Power Spectral Density units

I am trying to compare power spectral density values (obtained from dsp.SpectrumAnalyzer) with PSD values obtained from hardware which has a VSA. MATLAB's documentation says that " The power spectral ...
Saira's user avatar
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