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joma

Rtl DVB-T Problems

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Hi,

 

After today upgrade (Kernel / Firmware) my DVB-T pen stop working with dump1090.

 

Error message:

 

/usr/bin/dump1090 --net --gain -10 --modeac --net-bo-port 30005 --net-bi-port 30104
Found 1 device(s):
0: Realtek, RTL2838UHIDIR, SN: 00000001 (currently selected)
 
Kernel driver is active, or device is claimed by second instance of librtlsdr.
In the first case, please either detach or blacklist the kernel module
(dvb_usb_rtl28xxu), or enable automatic detaching at compile time.
 
usb_claim_interface error -6
Error opening the RTLSDR device: Device or resource busy
 
 
It's possible to revert the upgrade?

 

 

Thanks in Advance.

 

Jorge Mota

 

Orange PI PC

Jessie 3.4.112-sun8i

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Hi,

 

After today upgrade (Kernel / Firmware) my DVB-T pen stop working with dump1090.

 

Error message:

 

/usr/bin/dump1090 --net --gain -10 --modeac --net-bo-port 30005 --net-bi-port 30104
Found 1 device(s):
0: Realtek, RTL2838UHIDIR, SN: 00000001 (currently selected)
 
Kernel driver is active, or device is claimed by second instance of librtlsdr.
In the first case, please either detach or blacklist the kernel module
(dvb_usb_rtl28xxu), or enable automatic detaching at compile time.
 
usb_claim_interface error -6
Error opening the RTLSDR device: Device or resource busy
 
 
It's possible to revert the upgrade?

 

 

Thanks in Advance.

 

Jorge Mota

 

Orange PI PC

Jessie 3.4.112-sun8i

 

Hi! Had the same issue after upgrade! Really easy to solve:

 

Edit  /etc/modprobe.d/rtl-sdr-blacklist.conf

 

and add: 

 

blacklist dvb_usb_rtl2832u

 

Then reboot :) 

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Hi

I'm trying to get gqrx-sdr to work with my RTL 2832 DVBT dongle.

In spite of having the driver blacklisted it loads at start up but can be easily

removed by

rmmod dvb_usb_rtl2832u as root

No need to reboot and TV applications can use the dongle normally

Then you have to install pulse audio for an unknown reason

Here the strange behaviour begins:

At start the sound on an FM station is very poor. Only bits of sound in fact.

On a text console running Armbian monitor -m shows lots of fall back to 480MHz

although my well cooled CPU is around 30 degrees

waiting about 10 minutes it gets perfect

temperature rises to 45

and CPU clock stays at 1296 MHz

But waiting more the sound gets bad again at times.

htop shows that pulse audio is using a rather big % of CPU

The only other OS that allows me to use gqrx on my OPI PC is XFCE Kali.

There CPU frequency  is steady at 1540 MHz temperature is higher

and pulse audio use less CPU .

I managed to get a fixed 1296MHz CPU frequency by putting 

GOVERNOR =performance

in /etc/default/cpufrequtils

It changes absolutely nothing :D

So I believe my problems are due to pulseaudio which seems rather complicated

May be a fifo written at 44Khz and read at 48 or the opposite.

Any idea is welcome :wacko:

Edit :

Partial success I plugged a pair of USB speakers It is OK

So the problem seems to be somewhere between pulse audio and HDMI sound.

Now the CPU temperature rise to 54 degrees and it makes me happy because

since I used Armbian I thought that the big radiator I put on the CPU was useless :D 

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Hi

I'm trying to get gqrx-sdr to work with my RTL 2832 DVBT dongle. :D 

 

 

Could you put up a bit more information on how you are going, getting GQRX working.

 

Is it worth trying to do or is GQRX such a CPU intensive app it wont work effectively on a H3 processor.

 

I am very interested in any HAM related uses for my Orange Pi's.

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The problem when I first installed gqrx-sdr on my Armbian OPI PC is that it crashed

Starting it from a console there was a brief obscure allusion to pulseaudio

and a lot of messages :could not resolve property : pattern 10600

Those are not important at all.

The pulseaudio one is as it appears that Debian uses that by default and it is not used in Armbian

So you have to install it too.

Next problem is that if you want to use an RTL2832 dongle you get a message

saying that it is not available .

This is because Armbian loads the TV driver but you just have to type as root

rmmod dvb_usb_rtl2832u

I could not manage to get a correct audio on the HDMI but with either an USB speaker

or the analog audio output it works nice.

You may have to use a mixer in case the volume is muted.

GQRX can be quite CPU intensive if you try for example to view 2MHz while

demodulating an FM stereo signal.

I won't recommend using it without good cooling of the CPU.

In that case the sound gets bad and the launching console fills with zeros.

But it doesn't crash and stays reactive so you can correct parameters.

One interesting feature is that you can select Demod Off

then CPU use is much lower than in FM stereo

 

To load  back: the TV driver for the dongle :

modprobe dvb_usb_rtl2832u

Or simply unplug it and plug it again.

 

I have tried with success :

A Funcube dongle pro

An RTL dongle with E4000 tuner

An RTL dongle with R820 tuner

Forum for GQRX:

https://groups.google.com/forum/#!forum/gqrx

 

PS : The gqrx forum recommends to run  volk_profile.

Don't

It takes a long time and then nothing works any more :)

You have to delete/hide/rename the .volk dirctory in your home.

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