How do switch blocks and selector blocks in GNU Radio work?
Admin
These two get mixed up all the time in GNU Radio because they sound similar but solve slightly different problems. I’ll explain them intuitively first, then a bit more technically,…
Software
I am looking for a GNU Radio flowgraph on Github or elsewhere that shows me how to incorporate ability to choose between SDRs whilst running the program.
Here are some open-source GNU Radio flowgraphs / projects on GitHub that you can study or adapt when you want to choose between different SDR hardware sources (e.g., RTL-SDR, USRP,…
QT GUI Vector Sink in GNU Radio – does it show offset of the signal from centre?
Short answer: no — not by itself 🙂 The QT GUI Vector Sink does not inherently show frequency offset from centre. It just plots whatever numbers you feed into it,…
In GNU Radio how can I make positive complex number negative?
Nice, this is a very GNU Radio–ish question 🙂 In GNU Radio, a complex number doesn’t have a “positive” or “negative” sign the way a real number does. If you…
How to figure flush value for GMU Radio GRC flowgraph which changes frequencies regularly and where saved data must not include data from previous frequency?
How to figure flush value for GMU Radio GRC flowgraph which changes frequencies regularly and where saved data must not include data from previous frequency? Great question — this bites…
Presentations for GNU Radio Meeting 31/1/2026
Presentation for meeting: https://www.astronomy.me.uk/wp-content/uploads/2026/01/Talk-Demo-BAA-GNU-Radio-Meeting-DRAFT-260126@2300.pdf Andrew Sutowski’s attempt to answer homework from last meeting: My own attempts to answer homework from last meeting: Exercise: Create your own AM radio: https://www.astronomy.me.uk/wp-content/uploads/2026/01/BAA-GNU-Radio-Meeting-Exercise-AM-Radio-201225.zip Exercise:…
Push button blocks in GNU Radio, and how to continuously display a variable state such as the one changed by a push button or other mechanism
Is there push button block in GNU Radio Companion? Yep — there is 👍 In GNU Radio (QT GUI) you’ve got a couple of button-style options, depending on what behavior…
Data .txt Files & Timelapse Video of Data Collection of comparison between ezCol.py & ezColGR (GNU Radio version) on LRO-H2(SCRT) using same 150cm dish, feed and SDR 24-25/1/2026
These are both relatively long integration times on the Intel i5 MiniPC used for this experiment. The numbers are not equivalent – in both cases I attempted to obtain an…
How to use GLon.py in ezRA (Easy Radio Astronomy)
ezRA’s ezGLon.py program studies cross sections of the Milky Way, along one Galactic Longitude (GLon). ezRA’s ezGLon.py program processes *GLon.npz files. Above, the ezGLon.py program errored because it found *Gal.npz…
Easy Radio Astronomy Software (ezRA)
LRO-H2 Radio Telescope (150cm Solar Cooker Dish)
Radio observation in hydrogen line (1420MHz)