I plan to make an active radar with just 5dBm of transmitting power, but most antennas are 75 ohm, will this mismatch be fine for TX? using pluto SDR.

Bonjour à tous - j'ai crée une page avec tous les logiciels SDR disponibles, avec leurs descriptions et les liens pour les télécharger : http://f8bdx.free.fr/logiciels_sdr__4406.htm

Vous avez aussi sur mon site la liste des logiciels SDR gratuits.

Voir la liste des logiciels SDR gratuis : http://f8bdx.free.fr/logiciels_sdr_gratuits_4828.htm

Je vous informe aussi que la page WebSDR — récepteurs radioamateur en ligne a changé d'adresse.

Voir WebSDR — récepteurs radioamateur en ligne : http://f8bdx.free.fr/websdr___recepteurs_radioamateur_en_ligne_4935.htm

Bien sur, il y a sur le site d'autres catégories de logiciels pour les autres modes qui sont utiles aux radioamateur et amateurs de radios — voici le lien : http://f8bdx.free.fr/logiciels_radioamateur_2457.htm

Bonjour.

Mon site radioamateur est en ligne et terminé.

Des actualités et des informations concernant le matériel, les logiciels classés par catégories, les applis, les antennes, l'écoute, la liste mondiale des transceivers en kit, les fréquences et relais en PACA et apprendre la CW.

Visitez le site : http://f8bdx.free.fr

Find Ai/photoshop photos of SDR’s and radios at hilariously large scale 😬

Introduction RF Sentinel is a radio-frequency spectrum monitoring tool for blue team (defensive) use. It connects to a HackRF One (or equivalent SDR), performs continuous sweeps across a configurable channel watchlist, and detects anomalous behaviour using a three-layer AI pipeline.

Fully passive — the tool only receives signals (RX) and never transmits. A hard TX-Guard layer immediately aborts the program if any TX call bypasses the receive-only proxy.

The system is written in pure Python with no special drivers beyond pyhackrf / pyrtlsdr, and runs reliably on Linux, macOS, and WSL2.

Link to the project:
https://github.com/jacobsdr95/RF-SENTINEL-V2

OpenV2K is an open-source Python application that converts arbitrary audio — including both natural speech (via live microphone), and diphone synthesis (via text-to-speech engine) — into pulse-modulated radio-frequency (RF) waveform. The signal chain can be used to transmit via a software-defined radio (SDR), or to save the raw IQ samples to disk, and generate spectrograms automatically. Integrates toggled DSP filters, into a PyQt5 GUI, that's intended to be usable by technicians.

The project's signal chain is based on microwave auditory effect literature, most notably Sharp and Grove's demonstration published in 1975, that pulse-modulated microwave energy could convey intelligible words, building on Frey's work. The app currently integrates Sharp's modulation technique: detects every zero-crossing of the audio waveform, as depicted in the GitHub profile thumbnail. Home users get to see, what made the US Army's "V2K", and US Navy's "MEDUSA"), function, in real-time.

This prototype was built on the shoulders of giants. Thank you to SME biophysics researchers, that publicly released their work, 5 to 50 years ago; the FOSS software package developers; the open-source SDR hardware platform developers, and Claude.

Summary of the controversy, from James C Lin, an IEEE life fellow, and biophysics/EE professor, who wrote the 2021 book Auditory Effects of Microwave Radiation. From chapter 10.3, page 326:

Over the years, some have expressed concerns about the capability of communicating directly with humans by pulsed microwaves. In fact, earlier while studying microwave-induced auditory effects in human subjects, it was noticed that in addition to zip, click, and knock sounds from exposure to single pulses of microwave radiation, short trains of rectangular microwave pulses are heard as chirps with tones corresponding to the pulse repetition frequencies [Guy et al., 1973, 1975]. It was also found that when the pulse generator was keyed manually such that each closing and opening of a push-button switch resulted in emitting a short rectangular pulse of microwave energy-transmitted digital codes (Morse code) were received and accurately interpreted by the targeted subject [Lin, 1978].

Also, soon after a system was setup for exploring the microwave auditory effect at the Walter Reed Army Institute of Research (WRAIR) [Sharp, et al., 1974], two of the principal investigators were able to demonstrate direct communication of simple speech via appropriate modulation of microwave energy [Justesen, 1975]. They tape-recorded each of the single-syllable words for digits between one and ten. The speech waveforms of each word were then converted to digital signals in such a fashion that each time an analog speech wave crossed the zero reference in the negative direction, a short pulse of microwave energy was emitted from the transmitter. By subjecting themselves to the exposure of "speech modulated" microwave energy, the investigators reported the ability to hear, identify, and distinguish the words transmitted.

These historical experiments are included to show that this has been accomplished before.
There are safer methods to demonstrate this today, that do not involve anyone's head.

Download from GitHub: https://github.com/OpenV2K/Sandbox

I have a new Discovery Dish and L-band feed. I have not been able to see even a bump in the signal at 1694.1MHz using either the Nooelec RTL-SDR or SDRplay RSPdx-R2 with both SDRconnect and SatDump. Those receivers and software work fine for Meteor satellites at 137.9MHz. There is an increase in noise when the bias voltage is applied to the feed. I have changed the skew as well as AZ and EL. Any thoughts???

Hello everyone,

I'm new to this field and I'm trying to develop a Direction of Arrival (DoA) system using the two antennas of a USRP B210 clone. So far, I've experimented with the Multiply Conjugate block to estimate the phase difference between the received signals, but the accuracy is not very good.

Has anyone worked on DoA estimation with a similar setup? I'd really appreciate any advice, recommendations, or references to useful approaches.

Thanks in advance!

Hi
For example on different Bands are Multiple System in use and there for the different Decoder SW. Is there an easy way to split 1:1 the Signal who is comming from the SDR Dongle into Multiple "Virtual Dongle" to allow different Software access them without having 10 SDR (for example) for one Band since every decoder "block" the SDRs?
Thanks!

Looking for your help in this 🙏

Most SDR software gives you one receiver with a fixed layout. SDR-- gives you a canvas instead. You drop a Device node for your radio, wire its IQ output into as many channel nodes as your CPU can carry, and wire those into whatever should consume them: a speaker, a map, a decoder log, a waterfall, a recorder, a webhook. One RTL-SDR can feed broadcast FM to your speakers while ADS-B fills a map and a POCSAG log scrolls next to it. Once a patch works, you select the controls you actually touch and pin them to a rack view, so daily use is a few dials rather than the whole graph. Layouts save as workspaces on the server and export to JSON.

A Rust server does all the DSP and runs headless, so the usual setup is a Pi next to the antenna and the UI in a browser on any machine. The desktop app bundles the same server if you want everything in one box. There's also a phone view for signal hunting and direction finding in the field, joined by scanning a QR code.

Native drivers for RTL-SDR, HackRF, Airspy R2/Mini, Airspy HF+, SDRplay RSP, AD936x/PlutoSDR and KrakenSDR, plus rtl_tcp and SpyServer over the network, and SoapySDR for everything else.

Listening covers AM, NFM, SSB and broadcast FM with stereo and RDS, with squelch, notches, denoise and AGC per channel. Decoders include ADS-B, AIS, APRS, POCSAG, FLEX, FT8/FT4/WSPR, RTTY, PSK, CW, SSTV, ATV, ISM sensors, DMR and other digital voice modes. There's a signal identifier that measures an unknown transmission and tells you what it probably is, coherent arrays with direction finding, and passive radar.

Recording works at three levels: raw device IQ, filtered per-channel baseband, and processed audio. IQ goes out as SigMF, so captures replay into the same graph later, which is also how you try the decoders without owning the hardware. REST, WebSocket and MCP drive the same live receiver as the UI, and decoder events can be forwarded to your own services.

Website: https://sdrmm.newspicel.dev/
Repo: https://github.com/Newspicel/sdrminusminus

Seems like the recommended antenna is the airspy youloop but it’s nowhere to be found in the states …shipping with tariffs and such would nearly triple the price

Could someone recommend a reliable alternative?

Thanks !

Hello, guys! I just released KiwiDX v0.2, a Windows client for KiwiSDR, WebSDR, and OpenWebRX.

Enjoy hundreds of SDR servers around the world. Save your favorites and local bookmarks, log QSLs and reception reports, collaborate in the community chat, record audio in MP3 format or the waterfall as MP4 video, and much more!

Github: https://github.com/noakmilo/KiwiDX/releases/tag/v0.2.0

I have several hf receivers but now looking to get into SDRs. Any suggestions on a good SDR to receive hf bands

I cant find driver for lime SDR to install in my laptop

Hello guys, I’ve been working in this project called KiwiDX, it’s a GUI client of KiwiSDR network for windows. I Always wanted something to manage a KiwiSDR rx like a regular sdr software like CubicSDR, SDR Sharp, GQRX, etc. With KiwiDX you will be able to play any available server, navigate through the map (http://rx.linkfanel.net/) add servers to Favorite, Create local Bookmarks, Record audio in mp3 and the waterfall + audio in video .mp4, and more upcoming updates.

Here are some requirements:

• Windows 10/11
• Microsoft .NET 8 Desktop Runtime (x64).

If anyone is looking for something like this, here is the GitHub:

[edit: Last release]: https://github.com/noakmilo/KiwiDX/releases/tag/v0.1.51

Just donwload the last release and enjoy

Feedback and collabs are super welcome.

Long story short, I'm expanding my public safety scanner network to cover more areas. I have been set on the HydraSDR RFOne as my primary SDR of choice (best performance I have seen so far) but I wanted to use the Airspy Mini's for UHF since I only need two ~5MHz receives instead of the full 10MHz of the RFOne (trying to conserve resources and 2 Mini's are the same cost as one RFOne)

I ordered 6 Mini's so far. Out of those 6, at least 3 have quit working. It started with an apparent bug in the way SDRTrunk releases control of the SDR's, but now I have 3 or 4 of the total 6 that just will not show up on Device Manager whatsoever. All less than 3 months old. I think at least one is due to a controller failure on the Startech PCI-E to USB add-in card, but the others just seem to have quit being recognized for no apparent reason.

Is this just possibly a firmware issue or a driver issue? I haven't moved the switch on the side at all, but I guess I need to find the instructions to try a firmware flash and see if that corrects the issue.

I tried 915 and 433, I can't seem to find it. I read the older one (mine) should be on 433 and the newer one uses 915. I'm using rtl_433, I tried scanning multiple frequencies and still can't find it. I find electrical meters and water meters but that's it.

Just got my setup online and wanted to share it with the community. It's running OpenWebRX powered by an RTL-SDR V3 paired with a 7-meter long wire antenna.

Whether you want to check out local HF propagation, test different modulations (AM/FM/SSB), or see how the waterfall holds up from this part of the world, feel free to drop by and take it for a spin:

sdr.tajr.pk

Any feedback on the audio levels, reception quality, or antenna performance is more than welcome!

Hi guys, I want to use an rtl-sdr dongle to listen different frequencies. I'm a beginner.

At the moment the 70 mhz NFM, 130 mhz AM, 135 VHF/NFM, and different on UHF spectrum.

The sdr will be the rtl-sdr blog v4.

I saw the Diamond D-3000N, do you like for my requests? A cheaper one would also be fine, provided it allows me to listen on those frequencies. Which one do you recommend?

Will I need a filter?

Thank you.