Search results for: Spectrum Analyzer

SATSAGEN: Software to use a PlutoSDR as a Tracking Spectrum Analyzer

Thank you to Frank, HB9FXQ for submitting news about a new Windows program called SATSAGEN which allows you to use a PlutoSDR as a wideband spectrum analyzer. SATSAGEN was created by Alberto IU1KVL and is entirely free to use. This makes it possible to get wideband scans of RF components like filters and attenuators. Together with a directional coupler it could also be used to measure the SWR of antennas as HB9FXQ demonstrates in his Twitter post.

The PlutoSDR is a low cost RX/TX capable SDR with up to 56 MHz of bandwidth and 70 MHz to 6 GHz frequency range. It is typically priced anywhere between US$99 - US$149 depending on sales.

In the video below Alberto demonstrates SATSAGEN performing some wideband scans, and he shows the various features of the software. He writes that the system has a scan range from 70 MHz to 6 GHz and can show results in dBm. The spectrum analyzer works with the TX part of the PlutoSDR to provide a tracking generator with resolution of up to 1024 points. The software can also use the PlutoSDR as a frequency generator with 1 kHz of resolution.

There is also a support group available at

SATSAGEN Screenshot
SATSAGEN Screenshot


SDRplay Spectrum Analyzer Software Updated to V1.0a

Steve Andrew, the author of the SDRplay Spectrum Analyzer software has recently released an update which enables several new features. This software allows you to use SDRplay SDRs to scan a wide swath of bandwidth by rapidly scanning in 10 MHz (or less) chunks over the SDRplay's frequency range. The SDRplay team write:

We are pleased to announce the availability of V1.0a of the Spectrum Analyser software developed by Steve Andrew specifically for the RSP line of products. This is a very-much upgraded version of the original alpha release and includes many new features as well as removing the limitations imposed on the previous version. New features include multiple traces, a versatile marker system with maths, peak find and display functions, Zero or non-Zero IF options and an upgraded tracking generator system. Currently support are: 

RSPduo (single tuner mode)

SDRplay Spectrum Analyzer
SDRplay Spectrum Analyzer

RTL-SDR Retrogram: ASCII Art Spectrum Analyzer

Over on GitHub, Rakesh Peter (r4d10n) has uploaded a new terminal/ssh based console application called "retrogram~rtlsdr". This program uses an RTL-SDR and terminal window to display a spectrum analyzer drawn in ASCII art. Because it is terminal based, it is even possible to view the spectrum of a remote device over an SSH connection. The program is based on software designed for Ettus USRP SDRs, and has been adapted for RTL-SDR.

For other SDRs r4d10n has also worked on a "retrogram~soapysdr" version which should work with any SoapySDR compatible SDR, and "retrogram~plutosdr" for PlutoSDR SDRs.

Spektrum SV Mod: RTL-SDR Spectrum Analyzer Software Now with Improved UI

Spektrum is a popular spectrum analyzer program that is used with RTL-SDR dongles. It is based on the command line rtl_power software and is compatible with both Windows and Linux. Thanks to it's easy to use GUI it is an excellent piece of software for scanning and determining where active signals exist, or for measuring filters and antenna SWR with a noise source.

Recently SV8ARJ (George) and SV1SGK (Nick) have been working on extending the original open source Spektrum code. Their improvements focus around the UI and making it more functional and easier to use. Currently the updated branch is in alpha, and they are hoping that any testers could help report bugs, issues and wishes to them. The code is available on their GitHub and the latest Windows test build can be downloaded from their DropBox.

The changelog reads:

  • 2 Cursors for Frequency axis.
  • 2 Cursors for Amplitude axis.
  • Absolute and differential measurements with cursors.
  • Zoom functionality of the cursors's defined area (gain + frequency).
  • Mouse Wheel Gain adjustment on graph (Top area for upper, low area for lower).
  • Mouse Wheel Frequency adjustment on graph (left area for lower frequency, right for upper).
  • Mouse Wheel in the centrer of the graph performs symetric zoom in/out.
  • View/settings store/recall (elementary "back" operation, nice for quick zoomed in graph inspection).
  • Right click positions primary cursors.
  • Right Double Click positions primary cursors and moves secondary out of the way.
  • Left Double Click zooms area defined by cursors (Amplitude + frequency).
  • Left Mouse Click and Drag on a cursor moves the cursor.
  • Middle (mouse wheel) Double Click resets full scale for Amplitude and Frequency.
  • Middle (mouse wheel) Click and Drag, moves the graph recalculating limits accordingly.
  • Reset buttons to Min/Max range next to Start and Stop frequency text boxes.
  • Cursor on/off checkbox now operate on all 4 cursors.
  • ZOOM and BACK buttons.
  • Filled-in graph option (line or area).
  • Display of frequency, Amplitude and differences for all cursors.
  • Modified: Button layout.
  • Fixed: Save/Reload settings on exit/start. IMPORTANT : delete the "data" folder from the installation location if you have it.
  • Filling in graph option (line or area).
Spektrum UI Updates
Spektrum UI Updates

SDRplay Spectrum Analyzer Alpha Version Released

Steve Andrew has just released an alpha version of a Windows Spectrum Analyzer app for SDRplay SDRs that he's been working on. The app is currently still in alpha, meaning that all the features are not yet implemented. In particular, scans larger than the SDRplay's maximum bandwidth of 10 MHz are not ready yet. In the future the app will be able to scan swath's of bandwidth up to 2 GHz wide, similar to what SpectrumSpy for the Airspy and rtl_power for the RTL-SDR does.

We are pleased to announce the availability of the first cut of Spectrum Analyser software developed by Steve Andrew specifically for the RSP line of products. Please note that this is first alpha software and so it is still very much in development and some features are still to be added. Currently supported are:


This first alpha release gives a good idea as to the look and feel for the software. The main functional limitation is that sweeps of greater than 10 MHz are not currently supported. Steve is currently re-working the algorithms for providing wider sweeps than 10 MHz to improve sweep time and remove the issue of the DC spike in ZIF mode, so please bear with him.

We recommend using the software with AGC turned off and use manual control of the gain for better display stability.

Please use this forum thread to post any issues. Read the issues already raised and only post if the issue you have found hasn’t been raised. This will help Steve in his development.

Further development information can be found on the forum.

Click here to download the 0.9a Alpha release.

SDRplay Spectrum Analyzer Alpha
SDRplay Spectrum Analyzer Alpha

Viewing Drone Signals with HackRF being used as a Wideband Spectrum Analyzer

Over on his YouTube channel user Andy Clarke has uploaded a video where he demonstrates his HackRF being used as a wideband spectrum analyzer with the HackRF Spectrum Analyzer software. About a year ago the HackRF team released a new firmware update which enabled the HackRF to be able to sweep through the frequency spectrum at a rate of up to 8 GHz per second. This allowed the HackRF to be used as a wideband spectrum analyzer which is able to display an arbitrarily large swath of spectrum. Shortly after the firmware update spectrum analyzer program by 'pavsa' was released on GitHub.

In the video Andy demonstrates the HackRF being used to view the WiFi band and show a 2.4 GHz WiFi connection between a drone and it's controller. He also shows it working with a handheld radio and the uplink of his mobile phone. Andy hopes to use the HackRF to avoid losing his drones due to interference.

Software Defined Spectrum Analyser - Hack RF

Poor Mans Spectrum Analyzer with an RTL-SDR and Noise Source

Over on YouTube channel Bootstrap Workbench has been running a series on using an RTL-SDR and noise source to create a poor man’s spectrum analyzer. So far he has three videos available. The first shows how to install and setup Spektrum, his preferred Windows based wideband scanner for the RTL-SDR.

The second video shows how the RTL-SDR, noise source and Spektrum can be used to tune a cavity duplexer. A cavity duplexer is an adjustable set of filters that allows you to use a single antenna for TX and RX at different frequencies. It can be tuned by adjusting screws on the unit body.

In the third video he shows how to examine the response of a dual ferrite isolator/circulator which is a device that can be used to ensure RF only travels in one direction. This could be use for example to prevent damage to a TX power amplifier from reflected signals due to high VSWR or other nearby powerful signals.

Poor Man's Spectrum Analyzer – Installing Spektrum and Testing an RTL-SDR com 88-108 Bandstop Filter
Poor Man's Spectrum Analyzer – Tuning Cavity Duplexers
Poor Man's Spectrum Analyzer – Examining a Dual Ferrite Isolator/Circulator

If you’re interested in this we also have our own tutorial available about setting something like this up, but using alternative software.

HackRF Sweep Spectrum Analyzer for Windows

A few weeks ago the HackRF drivers and firmware were updated and one new feature added was hackrf_sweep. This new feature allows us to scan across the spectrum at up to 8 GHz per second, which means that a full 0 – 6 GHz scan can complete in under a second.

Previously only Linux software such as QSpectrumAnalyzer was compatible with hackrf_sweep, but now over on GitHub user pavsa has released a new Windows based Spectrum Analzyer which is compatible with hackrf_sweep.

We gave the software a test and it ran flawlessly with our HackRF. The features include:

  • Optimized for only one purpose – to use HackRF as a spectrum analyzer
  • All changes in settings restart hackrf_sweep automatically
  • Easy retuning
  • hackrf_sweep integrated as a shared library
  • Peak display
  • High resolution waterfall plot

Remember that to run the software you will need to have updated your HackRF to the latest firmware. The spectrum analyzer software is also Java based, so you’ll need to have the Java JRE for Windows x64 installed.