Mini-Circuits SLP-21.4+ Coaxial Low Pass Filter 50Ohm DC-22MHz Data Sheet
Admin
Download data sheet below: https://www.astronomy.me.uk/wp-content/uploads/2025/10/Mini-Circuits-SLP-21.4-Coaxial-Low-Pass-Filter-50Ohm-DC-22MHz-Data-Sheet-261025.pdf
Radio Astronomy
Was the Orionid meteor shower a flop this year?
The Orionid meteor shower is described by the Royal Museums Greenwich, London, website as: Orionids 22 October 2 Oct-7 Nov 15 Fast with fine trains. Associated with Comet Halley (https://www.rmg.co.uk/stories/space-astronomy/meteor-shower-guide-2025…
Two-core plastic-coated cable (e.g., speaker twin, figure-8) works fine for a VLF loop wound on a wooden cross
Two-core plastic-coated cable (e.g., speaker twin, figure-8) works fine for a VLF loop wound on a wooden cross. Here’s how to make it work well: So yes: two-core plastic cable…
Two-core plastic-coated cable (e.g., speaker twin, figure-8) works fine for a VLF loop wound on a wooden cross.
Short answer: yes—two-core plastic-coated cable (e.g., speaker twin, figure-8) works fine for a VLF loop wound on a wooden cross. Here’s how to make it work well: So yes: two-core…
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…
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…
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…