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As the title suggests, I would like to try to use an AVerMedia A835B USB dongle to receive radio signals (not just TV). Why? Because I happen to have one and would like to try to get it to work for this purpose if possible.

I have seen post such as this which talk about using gqrx with an "RTL" based receiver - obviously this does not work with my dongle, but I am hoping I can do something similar with this device.

FWIW, it appears that the dongle is recognised by my system. Following is the output of dmesg as pertains to the insertion of the receiver:

[  140.320451] usb 1-1.2: new high-speed USB device number 5 using dwc_otg
[  140.455205] usb 1-1.2: New USB device found, idVendor=07ca, idProduct=3835, bcdDevice= 2.00
[  140.455242] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[  140.455262] usb 1-1.2: Product: A835B
[  140.455279] usb 1-1.2: Manufacturer: AVerMedia TECHNOLOGIES, Inc.
[  140.455295] usb 1-1.2: SerialNumber: 202065500049
[  190.980613] dvb_usb_af9035 1-1.2:1.0: prechip_version=83 chip_version=02 chip_type=9135
[  190.989075] usb 1-1.2: dvb_usb_v2: found a 'Avermedia A835B(3835)' in cold state
[  190.993750] usb 1-1.2: dvb_usb_v2: downloading firmware from file 'dvb-usb-it9135-02.fw'
[  191.099255] dvb_usb_af9035 1-1.2:1.0: firmware version=3.40.1.0
[  191.099308] usb 1-1.2: dvb_usb_v2: found a 'Avermedia A835B(3835)' in warm state
[  191.099325] dvb_usb_af9035 1-1.2:1.0: [0] overriding tuner from 38 to 60
[  191.100211] usb 1-1.2: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer
[  191.100313] dvbdev: DVB: registering new adapter (Avermedia A835B(3835))
[  191.100330] usb 1-1.2: media controller created
[  191.102994] dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered.
[  191.141098] af9033 11-001c: firmware version: LINK 3.40.1.0 - OFDM 3.40.1.0
[  191.141139] af9033 11-001c: Afatech AF9033 successfully attached
[  191.141255] usb 1-1.2: DVB: registering adapter 0 frontend 0 (Afatech AF9033 (DVB-T))...
[  191.141293] dvbdev: dvb_create_media_entity: media entity 'Afatech AF9033 (DVB-T)' registered.
[  191.161875] it913x it9133bx-tuner.2.auto: ITE IT913X BX successfully attached
[  191.176878] Registered IR keymap rc-it913x-v2
[  191.177637] rc rc1: Avermedia A835B(3835) as /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/rc/rc1
[  191.178962] rc rc1: lirc_dev: driver dvb_usb_af9035 registered at minor = 0, scancode receiver, no transmitter
[  191.180028] input: Avermedia A835B(3835) as /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/rc/rc1/input2
[  191.181082] usb 1-1.2: dvb_usb_v2: schedule remote query interval to 500 msecs
[  191.181227] usb 1-1.2: dvb_usb_v2: 'Avermedia A835B(3835)' successfully initialized and connected
[  191.183183] usbcore: registered new interface driver dvb_usb_af9035

So, it appears that the receiver is recognised by my pi (running bullseye). But I can't seem to get past the point of finding some software that works with it.

Also, FWIW, i appear to have some dvb devices created when the driver loads:

glennm@adsb-test:/etc $ ls -l /dev/dvb/adapter0/
total 0
crw-rw----+ 1 root video 212, 0 May 24 19:57 demux0
crw-rw----+ 1 root video 212, 1 May 24 19:57 dvr0
crw-rw----+ 1 root video 212, 3 May 24 19:57 frontend0
crw-rw----+ 1 root video 212, 2 May 24 19:57 net0
glennm@adsb-test:/etc $

At the end of the day I would like to be able to use it as a general purpose receiver (as per the article I linked above ). I get that dvb relates to TV, but if I black list the driver (dvb_usb_af9035) obviously I don't get the dvb devices created (the method proposed in the gqtr article above), but I also cannot seem to find the link that enables me to get a piece of software working with this device.

What am I missing? Or am I attempting to do the impossible? Is there any software that supports this receiver as a generic radio receiver?

FWIW, I've tried googling various phrases involving af9035, A385B, sdr with raspberry pi, raspbian and other terms, but either I always get "there aren't many good matches" or video server examples - which is not what I am after.

The more I research this, the more I believe what I am trying is either non-trivial or not possible, but still would appreciate a second opinion.

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  • 1
    This isn't Pi specific. You are reducing the chance of finding solutions. Look for Linux solutions, not Raspberry Pi solutions.
    – joan
    May 26, 2022 at 9:26
  • What happened when you followed the steps outlined by the author of the article you referenced?
    – Seamus
    May 27, 2022 at 20:04

1 Answer 1

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It's been a while since I used one of these SDR dongles on my RPi, and I've never used the model that you've asked about specifically. Assuming it's a legitimate SDR receiver, the procedure you referenced looks competent, and should work. To verify, I've just plugged my Nooelec SDR dongle into my RPi 3B+ (bullseye)...

Let's check it out:

$ lsusb
Bus 001 Device 007: ID 0bda:2838 Realtek Semiconductor Corp. RTL2838 DVB-T
...
$ dmesg | gawk '/RTL283/ || /Realtek/'
[    4.634458] usb 1-1.1.2: Product: RTL2838UHIDIR
[    4.638049] usb 1-1.1.2: Manufacturer: Realtek
[  542.644751] usb 1-1.1.2: Product: RTL2838UHIDIR
[  542.644768] usb 1-1.1.2: Manufacturer: Realtek
[ 3142.583945] usb 1-1.1.2: Product: RTL2838UHIDIR
[ 3142.583962] usb 1-1.1.2: Manufacturer: Realtek

So here's the thing:

The RTL28xx ICs produced by Realtek Corp. were designed to demodulate DVB-T (digital TV) signals, and output the TV signal over the USB bus. However, Realtek's chips have an additional mode supporting reception of consumer FM radio. This feature was discovered by a kernel hacker, and drivers were developed that put this additional mode to use. This gave us the ability to re-purpose these devices as Software Defined Radio (SDR) receivers - more than just a TV receiver! For more on the story...

However not all DVB-T receivers have this additional mode. If you filter your dmesg as I've shown above, and you don't see any mention of Realtek or of RTL28xx, there's a fair chance you're only going to be watching television instead of learning about SDR.

As I see nothing in your dmesg listing, I'm afraid you're only going to watch TV with that AverMedia USB stick. Sorry about that. But the good news is RTL-SDR dongles are still readily available and super-cheap given their capabilities.

And the answer to your question is, "No - it is not possible to use an AverMedia A835 USB dongle as a general-purpose radio receiver."

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  • Thanks for that, you have confirmed my own research, but I still had to ask just in case I missed something. FWIW, it does receive TV - so at least there is that :-) I do have some RTL dongles on (back) order, so I will park this until they arrive. Thanks again for your reply.
    – GMc
    May 29, 2022 at 1:19
  • @GMc: Thanks for asking :) Your question prompted me to dig my RTL-SDR out of the parts bin, and reading about gqrx I decided to try it on my Ubuntu system. Unfortunately, it seems the package is broken - or poorly documented, but the installation is now on my "to-do" list.
    – Seamus
    May 29, 2022 at 16:56
  • All the best with that @Seamus, FWIW, I have a FlightAware (rtl-sdr stick) which works well with dump1090-fa and the flight aware package for producing a radar like display of aircraft near me. When I get my next receiver, I will explore gqrx and some other packages mentioned in this post .
    – GMc
    May 31, 2022 at 7:56

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