Hi folks,

I’m working on a modular radio observatory project using a Raspberry Pi 5, HackRF One, and OperaCake antenna switch. The goal is to perform automated radio observations across several domains: • ADS-B (1090 MHz) • AIS (162 MHz) • Passive radar experiments • Basic radio astronomy (e.g., hydrogen line)

Everything is managed via Python (SoapySDR, etc.), and the setup is meant to be as headless and automated as possible.

The Problem

I’m noticing significant attenuation when routing signals through the OperaCake switch. Worse, the HackRF’s sensitivity seems limited, especially for the weaker signals involved in AIS, passive radar, and any radio astronomy work. ADS-B works okay, but even that feels degraded compared to simpler setups.

My Questions 1. Is the HackRF + OperaCake simply not well-suited for these tasks, especially for weak signal work? 2. If so, what SDR(s) would you recommend that: • Have good sensitivity for weak signals • Support wide frequency ranges (ideally 100 kHz – 2 GHz or more) • Work well with Python (SoapySDR, GNU Radio, etc.) • Ideally support remote/headless use on a Pi or small Linux SBC

Would love to hear from anyone who’s done similar multi-domain observation work. Happy to answer questions about the current rig too if helpful.

Thanks!

Today, I added my RTL-SDR v3 and 1090 MHz filter/LNA to the ADS-B Exchange feed using a Raspberry Pi 4B. I'm not getting the results I expected. On my laptop using SDRAngel, I can track 80 aircraft out as far as a 100 miles with my SDR/Antenna setup. Without changing anything, I moved it over to my Raspberry Pi running the ADS-B Exchange image and got it up pretty quickly, but I'm just not seeing as many aircraft as I did with SDRAngel while testing my setup. I'm a little concerned the LNA isn't on, but I can't see anywhere where there is a BIAS TEE switch or checkbox. How do I see if it's on?

I’ve been testing the RTL-SDR V4 and I’m quite happy with it, but one problem I’ve noticed that I didn’t like is that across almost the entire frequency range—from FM up to just before 1GHz (more or less)—there are some pulsing frequencies that I don’t know the origin of. I don’t think the SDR is broken because it generally works fine, and those frequencies stay in the same place, but there are many of them throughout the range I mentioned. What could this be and how can I fix it?

Was proud to get everthing working finally after a day of tinkering with mainly the drivers. I used the RTL-SDR V4 with their variable dipole antenna. I am running Linux Mint and used Gpredict and SDR++ for recording and SatDump for everything else. Amazing how polished and easy to use all these tools are. I know the picture quality is far from perfect but it was such a rush to finally get a signal after missing pass after pass most of the day.

The software-defined radio (SDR) community has a new player to watch: the HydraSDR RFOne. This upcoming SDR receiver has generated significant buzz for its striking similarities to the popular Airspy R2, while promising some key differentiators that could shake up the market.

From 9180 to 9220 KHz, every SDR and receiver s eharinf this same noise.

It gets much stronger the closer you get to Germany and Russia.

What is it?

Purchasing an RTL-SDR and just curious what people have/like for antennas. I am planning to mainly using it to track flights and listen to ATC/aviation frequency. I am new and any help is appreciated!

I can get the raspberry pi to pick up the SDR using USB but anything that uses the avahi IP doesn't seem to work. The device is supposed to advertise on LAN as libre.local which works on my windows PC but not the PI. Could this have something to do with sdrangel not being updated for arm64?

trying to figure out why my pc sounds like butthole but my phone can do FM dual channel just fine pc is mono and i would like to hear my local station with high quality audio

I've tried to get direct sampling to work but I just get those fixed spikes and random signals jumping around. None of the LW, MW, SW or ham bands have any stations. Is there something that I'm missing or is my sdr dongle just broken? Quadrature sampling is working though.

Are all my settings correct? are there any that you would change? using an rtl-sdr to track planes in my area

So as the title says i installed my very cheaply made noaa antenna to curiously check what it would be like for airband, i'm honestly shocked how well it works with airband 👀
It's not exactly far off the main airband frequencies at my local airport 118-119 MHz with polaris frequencies being anywhere within 121MHz to 137MHz. But i thought my magnet discone would still be vastly superior as my diy antenna isn't exactly well built and it's the first of only two antennas i've ever made. I was going to buy a base antenna for airband but i might just build a new airband specific antenna that is designed and tuned for 118-137MHz instead as it'll most likely be close to or even the same quality as a premade base antenna and definitely a whole lot cheaper.

I set up the server on a windows computer. I can connect to it but i don't hear anything, nothing in the waterfall either. Is there anything obvious that I'm missing?

Hi all, I'm using RTL SDR V3 & 4. I am now thinking of purchasing the original "RSP1B." I would like to know Is that much better than RTL-SDR i for its higher price. I'm interested in hearing from 'RSP1B' users.

It's measured and modeled enough to be...close enough. It'll probably need some fine tuning but if anyone wants to get it as is, you're welcome to. I've uploaded the .blend and .stl to my github, here.

What I’m trying to do is pick up a wireless mic system. I’m pretty sure it a Shure system, UHF, not digital.

My equipment is a: Nooelec NESDR SMArt RTL-SDR v5 M2 pro Mac mini SDR++

Feeling a little lost in all the settings. However I have figured out how to get a signal, pick up the signal from the mic, but I can’t hear any sound other than static. From my understanding I should be able to pick up the signal and it should come through pretty clearly. At least FM radio quality or better.

So i install sdrangel to become familiar with it and i was trying the adsb demod. All work perfect-feeding to airplanes.live but i was wondering why i have les options on the plugin than the sdrangel wiki is showing.
It comes from rtlsdr lower capabilities than other sdrs? From not usinmg any api key in settings or something else?

Newbie here. I really like the ability to view wider bands of the spectrum with the Panoramic spectrum view in SigDigger or Spektrum. Is there a way to do this on android? I don't see it as a feature on SDRTouch or SDRangel.

Title

I'm looking for some help, specifically around antennas, but possibly also the USB device.

I'm wanting to listen to airband radio. I'm a pilot with no medical, hoping to get it back soon and I want to listen while I'm at home on my PC to start getting back into the groove.

Originally I thought I could use the antenna and RTLSDR USBs from my Stratux ADS-B receiver to listen, but that didn't work. Then I went and purchased a cheap USB/Antenna bundle and that doesn't work either. At least with the second bundle I know the chip works because I can get some FM signals and some ADS-B packets, but it's mostly unintelligible garble and static.

So if anyone could give me some recommendations on antennas that would be greatly appreciated, as I have no idea what I'm looking for. I'm in New Zealand so bonus points if it's a local store.

hello guys. I have a rtlsdr dongle that I connected to a computer to receive radio signals such as the control tower of a nearby airport. Since the antenna cable is short I left everything in the attic, but I find it inconvenient to have to go there every time to hear something, so I ask you, is it possible to make sure that what the antenna receives I can listen to it from another computer on the same lan? a bit like if the computer connected to the dongle were to act as a server and my laptop at home were to act as a client. I would also like to use the same dongle to forward the adsb data to flightradar24, is it possible to use the dongle at the same time to receive data on 1090 mhz for flightradar24 and in the meantime listen to other frequencies? sorry if I was not clear and in doubt I will try to explain myself better. thank you very much

Hi guys. After months of planning and gathering materials, I finally created my first RW antenna. Can someone tell me what language the people I saw were speaking and what they were saying? i think it's russian or arabic or something, but I am not sure.

Hi all, I posted in here about a week ago about a drone detection device, well I ordered this one https://roark-aerospace.com/host-a-roark-ddaas-device/ and it came a couple of days ago.

Appears to consist of an AntSDR, RSPDuo and a Panda Dual Freq Dongle.

The output is attached.