kana
op25
Our great sponsors
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
kana
-
Ask HN: What weird technical scene are you fond/part of?
usig modern web technologies to develop high performance scientific applications. We built a highly optimized, interactive and exploratory application for single-cell data analysis[1]. it runs purely in the browser with no backend and scales upto 200K cells. similar efforts include the biowasm project [2].
op25
-
How can we convert a DMR signal into clear voice by RTL_SDR?
I have no experience with DMR myself, but my understanding is that the Boatbod fork of OP25 has experimental DMR support, and I believe SDRTrunk software does, too.
-
Ask HN: What weird technical scene are you fond/part of?
Using OP25[1] with RTL-SDR dongles to implement scanners for trunking P25 radio systems on a computer. And as a sidebar to that, listening in on geographically remote public safety radio systems using Broadcastify[2]. It's basically the old "radio scanner" culture, but taken online and distributed worldwide. People listen to all sorts of stuff, but given my background as a former firefighter and former 911 dispatcher, my main interest is listening to public safety dispatch stuff.
That said, another commenter below mentioned modern "phreaking" and how it's become more radio centric... and while I won't admit to doing anything illegal, let's just say that there's some interesting stuff you can do / look at / listen to these days, especially with ubiquitous and inexpensive SDR hardware and related resources. See the recent story about the KrakenSDR passive radar stuff, and some of the papers that are out there about P25 security flaws, some of the automobile hacking stuff that's RF based, etc., etc. There's a fascinating world out there buzzing around on invisible electromagnetic fields... and you can tap into it with a $30 dongle and a Raspberry Pi (or your PC).
-
Is this encryption or frequency hopping or just not FM modulation? Not law enforcement, just a school they use Motorola handhelds.
If it's P25 Phase I or Phase II then SDRTrunk might work. boatbod's op25 might be another option, but more complicated to set up.
-
Using a Raspberry Pi without a GUI to stream scanner audio to a phone
I don't have a full guide for you, but I use https://github.com/boatbod/op25 for receiving and decoding P25 Phase 1 digital signals on the command line.
-
What do you use your homelab for?
op25
What are some alternatives?
sdrtrunk - A cross-platform java application for decoding, monitoring, recording and streaming trunked mobile and related radio protocols using Software Defined Radios (SDR). Website:
gqrx - Software defined radio receiver powered by GNU Radio and Qt.
sdrangel - SDR Rx/Tx software for Airspy, Airspy HF+, BladeRF, HackRF, LimeSDR, PlutoSDR, RTL-SDR, SDRplay RSP1 and FunCube
dsd - Digital Speech Decoder
rdio-scanner - Rdio Scanner is an open source software that ingest and distribute audio files generated by various software-defined radio recorders. Its interface tries to reproduce the user experience of a real police scanner, while adding its own touch.
rtl-sdr - library for turning a RTL2832 based DVB dongle into a Software DefinedReceiver; mirror from https://gitea.osmocom.org/sdr/rtl-sdr
multimon-ng
SVM-Face-and-Object-Detection-Shader - SVM using HOG descriptors implemented in fragment shaders
AdGuardMV3 - AdGuard browser extension prototype based on the new Manifest V3
new-wave - Stack Computer Bytecode Interpreters: The New Wave
FreePSXBoot - Exploit to allow loading arbitrary code on the PSX using only a memory card (no game needed)
rtl-power-fftw - Power spectrum for RTLSDR dongles.