[HN Gopher] Detecting Starlink Satellites with a Portable Raspbe... ___________________________________________________________________ Detecting Starlink Satellites with a Portable Raspberry Pi and RTL- SDR (2022) Author : ctoth Score : 65 points Date : 2023-03-03 19:47 UTC (3 hours ago) (HTM) web link (www.rtl-sdr.com) (TXT) w3m dump (www.rtl-sdr.com) | sgtnoodle wrote: | I always bring this up in the hope that it's seen by someone that | has deep knowledge on the subject. The Raspberry Pi's USB 2.0 | implementation seems to be horribly inefficient. An RTL-SDR uses | over 40% of a CPU core on a Pi 4 just doing USB transfers. It's | less than 5% on a typical laptop, as well as on other aarch64 | SoMs such as Nvidia Xavier. What's going on? Is the peripheral | itself just really cheesy? Is the driver not using DMA when it | could be? | nimbius wrote: | wild. does anyone know if linear polarization is specific to | starlink? youd imagine a circular polarization would make for | better reception over all. | | the second example in the video may have failed as the | directionality/alignment of the LNB and the use of a parabolic | dish are typically encouraged for best satellite reception | results. a Dish TV or direcTV setup for about $10 at a junkyard | might outperform? i dont think these "branded" setups are as | discrete or fine tuned as the author suggests. | | https://www.reddit.com/r/Starlink/comments/s83ahf/using_dire... | | ive been using PI and RTL/SDR to decode ADS-B for about a year | now and i gotta say the temperature issues aside it works a | treat. just waiting to see ole muskys jet pop up at some point ;) | CliffStoll wrote: | Absolutely sweet! | | What a delight to see a rasp-pi enthusiast mix satellite | detection with antenna design and junk box hacking! | | Long ago, this was the ham radio mindset... still is, for some. | lxgr wrote: | Speaking of ham radio mindset, I'm continuously amazed by the | existence of VHF and UHF amateur radio relay satellites, as | well as the ham station on the ISS. | | It doesn't seem like pointing a handheld radio at the sky could | possibly be enough to talk to astronauts, yet it seems to work! ___________________________________________________________________ (page generated 2023-03-03 23:00 UTC)