Search found 122 matches

by hotpaw2
Wed Jan 31, 2018 6:10 pm
Forum: Troubleshooting Help
Topic: NooElec NESDR SMArt - Error: Cannot access RTL device
Replies: 4
Views: 5133

Re: NooElec NESDR SMArt - Error: Cannot access RTL device

I also helps to have more than one RTL device available to test, to see if the problem is with software or with hardware. I had one of the smaller NooElec devices get hot and fail.
by hotpaw2
Mon Jan 29, 2018 9:04 pm
Forum: RTL-SDR Discussion
Topic: Looking for SDR software with plugins
Replies: 3
Views: 2273

Re: Looking for SDR software with plugins

On my Raspberry Pi, running a Linux variant, I use rtl_tcp to connect to the RTL-SDR, and plug my own DSP software (filters, demodulators, spectrum visualization, etc.) directly into the tcp-ip socket IQ data stream from rtl_tcp, which is an extremely simple interface to the raw IQ data.
by hotpaw2
Fri Jan 05, 2018 8:08 pm
Forum: Other SDR Devices
Topic: Airspy HF+ on a Raspberry Pi?
Replies: 4
Views: 5991

Re: Airspy HF+ on a Raspberry Pi?

The issue turned out to be that the permissions in the udev rules on the Raspberry Pi were different between default installations of the RTL-SDR library and the HF+ library. Changing either the user's group, or the device permissions, or the udev rules fixed the issue. After fixing this issue, the ...
by hotpaw2
Wed Jan 03, 2018 9:36 pm
Forum: Other SDR Devices
Topic: Airspy HF+ on a Raspberry Pi?
Replies: 4
Views: 5991

Airspy HF+ on a Raspberry Pi?

Has anyone got an Airspy HF+ working on a Raspberry Pi? I can compile and run SDR applications that link to libairspyhf on macOS. And libairspyhf builds and links without error on my Raspberry Pi 3. But the same code that runs on my Mac, reports no Airspy HF+ devices found on the Raspberry Pi. The c...
by hotpaw2
Sat Oct 21, 2017 1:27 am
Forum: RTL-SDR Discussion
Topic: How does the image rejection filter in the R820T(2) work?
Replies: 6
Views: 5568

Re: How does the image rejection filter in the R820T(2) work

So why is 65dB image rejection mentioned in the data sheet specification?
by hotpaw2
Mon Oct 09, 2017 5:48 pm
Forum: Troubleshooting Help
Topic: Command to rtl_tcp
Replies: 1
Views: 2796

Re: Command to rtl_tcp

There are both command-line options when starting rtl_tcp, and 5 byte parameterized-command messages that can get sent to the tcp socket/port when the socket is open (usually on port 1234). You can find source code to rtl_tcp here: https://github.com/osmocom/rtl-sdr/blob/master/src/rtl_tcp.c (Note t...
by hotpaw2
Sun Aug 20, 2017 11:46 pm
Forum: RTL-SDR Discussion
Topic: Weird interference and reception
Replies: 2
Views: 3475

Re: Weird interference and reception

Hi there, I am very confused as to what's going on here, I have a ground plane antenna designed fr air band My current location picks up the police fine, but not the tower, if I lean the antenna back 10cm it pick's up tower but not police. Also getting some kind of interference any help would be ap...
by hotpaw2
Mon Aug 07, 2017 4:53 pm
Forum: RTL-SDR Discussion
Topic: raspberry pi 2 make a lot of noise
Replies: 4
Views: 4521

Re: raspberry pi 2 make a lot of noise

Hi I asked in an other Forum but there was no solution. The Pi make a lot of noise! :o I cant use the Dongle for reception its insane how noisy it get and its impossible to receive anything. The Pi is in a Metal Case. :roll: I put the RTL-SDR dongle on a USB extension cable (with ferrite beads on i...
by hotpaw2
Thu Jul 20, 2017 4:05 pm
Forum: User Projects
Topic: Demodulate FSK
Replies: 6
Views: 19379

Re: Demodulate FSK

If you want to do this in code (your own program), and you know the bit or baud timing plus the two FSK frequencies, then two running Goertzel filters will work. They are roughly equivalent to narrow band-pass filters. Just take the difference of the two Goertzel filters magnitude outputs and look f...
by hotpaw2
Thu Jul 13, 2017 3:58 pm
Forum: RTL-SDR Discussion
Topic: I will make a SDR Spectrum software.
Replies: 3
Views: 2946

Re: I will make a SDR Spectrum software.

I will make a SDR Spectrum software. I want to know that RTL2832 only send RAW DATA(RF-signal digitalised)???? hent I just get these raw Rf stream data from USB (Yes, I will install driver for linux of this chip) and Then do FFT to these stream, Then I will get spectrum. You have the basic idea. An...