How to change an username on Linux Ubuntu
Admin
To change a username in Ubuntu cleanly and safely, follow these steps from a different admin account (not the one you’re renaming) — or from a root shell. ⚠️ Important:…
2025
Extreme difficulty detecting Jupiter or Saturn at 10 GHz.
From SARA meeting 19/10/2025: Eduard Mol: Just found Joachim Köppens planet observations at 10 GHz, I believe he used a 7.2 metre dish: http://sat-bodenstation-roenne.uni-kiel.de/. Jupiter was only 0.015 dB! Saturn…
Controlling Skywatcher mounts on Linux
Hi Andrew — good to see your interest in Linux astro-control setups (especially given your radio astronomy background!). For a Sky‑Watcher mount (SynScan-based) under Linux, here’s a breakdown of what…
Compare specifications of SDRplay RSP1, RSP2, RSPDuo, HackRF, PlutoSDR, and USRP B210 USB Software-Defined Radios.
Compare RSP1 RSP2 RSPDuo HackRF PlutoSDR USRP. Here’s a practical, spec-level compare of the popular SDRs you named, with notes for radio astronomy / interferometry use. Device RX freq. range…
Test data from LRO-H2, using GNU Radio and RSPduo 16/10/2025
https://www.astronomy.me.uk/wp-content/uploads/2025/10/DSES251016_10.txt Not worked! This first attempt to generate GNU Radio Companion GRC script with SDRplay RSPduo SDR which creates data files in ezRA’s ezCol.py .txt format does not appear to…
Is it beneficial to increase the physical size or number of turns of wire on the cross of the antenna used in a VLF SID Monitoring system?
Generally, the bigger the better within practical limits. Consider its orientation (N-S or E-W), where it will be located, will it be moved, will the mount support the weight of…
How to build a horn antenna at 1420 MHz
Building a horn antenna tuned for the 21 cm (1420.405 MHz) hydrogen line is a popular and effective way to do amateur radio astronomy. A horn antenna is especially good…
Measuring Earth’s Orbit at 1420 MHz
I asked ChatGPT how to do this, and here is its suggestion:
WR-650 Waveguide
WR-650 already covers 1.12–1.70 GHz, so 1.420 GHz sits comfortably in-band—you don’t need to resize the guide. What you do need is a simple, well-tuned coax-to-waveguide probe with a backshort…
WR-14 Waveguide
The WR14 waveguide (also known as WH14) is a rectangular waveguide used for millimeter-wave applications in the K-band. Here are the key technical specifications: Parameter Value Designation WR14 (WH14) Frequency…