British Astronomical Association Hydrogen Line Group (BAA H-Line Group) Meeting 1st September 2025
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The video from this meeting is available here:
Radio observation in hydrogen line (1420MHz)
How to take the signals from multiple antenna pairs and turn them into an actual sky image using Fourier transforms
Good question — you’re asking about the heart of radio interferometric imaging: how to take the signals from multiple antenna pairs and turn them into an actual sky image using…
Adding 2nd monopole onto cantenna to improve signal reception
Two monopoles at 90 degrees in cantenna One connects to splitter immediately Two connects via coax either 1/4 wavelength or 5/4 wavelength (more practical length = 26.5cm x 66% (velocity…
How do I normalise data from multiple radio telescope systems so I can combine them together?
How do I normalise data from multiple radio telescope systems so I can combine them together? Great question, Andrew. Here’s a practical, radio-astronomy-friendly playbook for putting multiple systems onto the…
GPIO Labs 1420 MHz amplifier and filter
Provides an alternative to the Nooelec SAWBird H1 low noise amplifier and filter for hydrogen line radio astronomy. Currently the SAWBird is not available. I have not myself used the…
Is there a tutorial from Bonn University that demonstrates how professional astronomers convert raw radio data—particularly HI 21 cm observations?
You’re asking about a tutorial from Bonn University that demonstrates how professional astronomers convert raw radio data—particularly HI 21 cm observations—into calibrated intensity measurements. Here’s what I found: Resources at…
How professionals convert raw telescope voltages into intensity maps of hydrogen in different parts of the Milky Way
Great question, Andrew — this is right at the heart of how the Milky Way has been mapped in neutral hydrogen (HI) at 1420.405 MHz. Professional radio astronomers follow a…
Comparing “RTL2832U SDR” vs “RTL-SDR V3”
Here’s an image of the RTL-SDR Blog V3 dongle for reference. Comparing “RTL2832U SDR” vs “RTL-SDR V3” What’s in a Name? What Makes RTL-SDR V3 Stand Out? TL;DR: V3 vs…
Latest LRO 2D Map of Milky Way Arms 2 September 2025
Result of combining entire available data set start of data collection up to 17 August 2025, from LRO 1, 2, and 3 hydrogen line radio telescopes.
Fly-through of 3D plot of Milky Way Spiral Arms created using data from LRO 1, 2 and 3 radio telescopes from start of data collection to 17 August 2025 (extended 3D slices revised version 4 September 2025)
Compare the 3D results below with 2D map using same data: Latest LRO 2D Map of Milky Way Arms 2 September 2025 – astronomy.network The Website of Lichfield Radio Observatory…