Re: [Discuss-gnuradio] Digital Audio Broadcast (DAB), anybody running gr-dab?
Hi Ruben and all, thank you for your response. I am not sure if my last response found it's way to you and the list. Nevertheless it contained a typo error. To keep it short: I could just test it again and indeed the -c switch (fine frequency correction) did the trick. Both USRP N210 and an rtl-sdr dongle work perfectly. Am Mittwoch, 26. August 2015 18:01 CEST, Ruben Undheim li...@beebeetle.com schrieb: (...) Extending the code to support audio reception will be happily appreciated. I was intending to do that, but I was a bit overwhelmed back them, and didn't get time for it. It should not be very hard according to Andreas. I'm not aware of any other GNU Radio code that supports audio reception. Anyone else? Before receiving audio I think a few additions have to be made to the fib_sink_vb_impl class. The process_fig method needs to be extended to support more FIG types and their extensions. I tried to do that on my own yesterday, but it is quite exhausting -- you really need some time to read the standard and implement the code. Nevertheless the project is really well-prepared and it's pretty nice to already work on bits instead of symbols as the signal processing, demodulation and channel decoding is already done. There is another nice DAB project at [1], but as far as I have seen it is not based on gnuradio. Nevertheless USRPs are supported via UHD (not sure if yet available as not displayed in the GUI) and several other hardware. Though I haven't compiled it because of lack of dependencies on my Linux Mint. In my Win7 VM I have trouble to get the rtl-sdr driver issues resolved. In /src/backend you find their fib_processor. An MSC handler is implemented as well (for DAB/MP2, DAB+/MP4). Cheers Matthias [1] http://www.sdr-j.tk/index.html ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] ALC662 audio card causes underruns and overruns
Make sure you're using 'plughw:' for the audio device so the driver does resampling (check ALSA docs). Without looking at the flowgraph, I'd guess this is a clock domain problem and your new computer (and audio card) clocks are somehow different than your old ones. On 08/28/2015 04:40 AM, Murray Thomson wrote: Hi, I have a flow graph that receives, demodulates and filters a signal before sending it to the audio card. It's been working in a single board, single core, computer with an audio card ALC888 for months. I occasionally had underrun messages, specially when changing filter parameters. This messages were normally less than 10 and very spread, about every 30 seconds. It didn't cause any noticeable noise or problems. Recently I moved to a better computer with better CPU, 4 cores and a ALC662 audio card. The Python script works fine, with no visible bottlenecks in the processor. However, I now get constant overruns and underruns reported, making the audio noisy. The audio card is able to work correctly when using the speaker-test command so, there isn't a fault in the hardware. It's also capable of running at the required sample rate. Is there any test I could make to understand and fix this issue? Has anyone had a bad experience using this audio card with GnuRadio? Thanks, Murray ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] ALC662 audio card causes underruns and overruns
Hi, I have a flow graph that receives, demodulates and filters a signal before sending it to the audio card. It's been working in a single board, single core, computer with an audio card ALC888 for months. I occasionally had underrun messages, specially when changing filter parameters. This messages were normally less than 10 and very spread, about every 30 seconds. It didn't cause any noticeable noise or problems. Recently I moved to a better computer with better CPU, 4 cores and a ALC662 audio card. The Python script works fine, with no visible bottlenecks in the processor. However, I now get constant overruns and underruns reported, making the audio noisy. The audio card is able to work correctly when using the speaker-test command so, there isn't a fault in the hardware. It's also capable of running at the required sample rate. Is there any test I could make to understand and fix this issue? Has anyone had a bad experience using this audio card with GnuRadio? Thanks, Murray ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] SDR R820T2
Hi Pedro, i dont know about your linux distro or the way of your gnuradio installation. You need the gr-osmosdr package for the RTL block in gnuradio. You have to blacklist the dvb_usb_rtl28xxu module in your modprobe configuration. This are the basics in a short for driving RTL sticks in gnuradio. Andy Am 27.08.2015 um 21:54 schrieb Pedro Gabriel Adami: Good afternoon, I bought the SDR R820T2 (you can see it on: http://www.amazon.com/NESDR-Mini-Compatible-Packages-Guaranteed/dp/B00P2UOU72) and now I have to configure my Gnuradio to use with my SDR. Do you know the steps to do it? I found some websites, but they seem a little confuse. Please, It would be great if someone could help me. Thanks a lot. -- Cheers, Pedro Gabriel Adami ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] R820T2 in Gnuradio
Hello, I followed some instructions and I installed the files in Gnuradio which respect to R820T2. Now, to start and continue my research, I need some tutorial to teach me to use this device and how to make a communication between Gnuradio and R820T2. Please, can anyone help me to find this? Or maybe you have already used this before. Thanks a lot. -- Cheers, Pedro Gabriel Adami ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] ALC662 audio card causes underruns and overruns
Also make sure that the ALC662 also supports the audio sampling rate you're using -- 44100 is the only rate I've been able to use on any platform [1]. Best regards, Marcus [1] http://gnuradio.org/redmine/projects/gnuradio/wiki/ALSAPulseAudio On 28.08.2015 12:31, Jeff Long wrote: Make sure you're using 'plughw:' for the audio device so the driver does resampling (check ALSA docs). Without looking at the flowgraph, I'd guess this is a clock domain problem and your new computer (and audio card) clocks are somehow different than your old ones. On 08/28/2015 04:40 AM, Murray Thomson wrote: Hi, I have a flow graph that receives, demodulates and filters a signal before sending it to the audio card. It's been working in a single board, single core, computer with an audio card ALC888 for months. I occasionally had underrun messages, specially when changing filter parameters. This messages were normally less than 10 and very spread, about every 30 seconds. It didn't cause any noticeable noise or problems. Recently I moved to a better computer with better CPU, 4 cores and a ALC662 audio card. The Python script works fine, with no visible bottlenecks in the processor. However, I now get constant overruns and underruns reported, making the audio noisy. The audio card is able to work correctly when using the speaker-test command so, there isn't a fault in the hardware. It's also capable of running at the required sample rate. Is there any test I could make to understand and fix this issue? Has anyone had a bad experience using this audio card with GnuRadio? Thanks, Murray ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] ALC662 audio card causes underruns and overruns
Thank you for your suggestions. The card supports 96 KHz and I'm using hw. I'll try to use plughw. I've solved this problem upgrading to the latest kernel in 12.04 which is 3.13.0-62. Regards, Murray On 28 August 2015 at 13:52, Marcus Müller marcus.muel...@ettus.com wrote: Also make sure that the ALC662 also supports the audio sampling rate you're using -- 44100 is the only rate I've been able to use on any platform [1]. Best regards, Marcus [1] http://gnuradio.org/redmine/projects/gnuradio/wiki/ALSAPulseAudio On 28.08.2015 12:31, Jeff Long wrote: Make sure you're using 'plughw:' for the audio device so the driver does resampling (check ALSA docs). Without looking at the flowgraph, I'd guess this is a clock domain problem and your new computer (and audio card) clocks are somehow different than your old ones. On 08/28/2015 04:40 AM, Murray Thomson wrote: Hi, I have a flow graph that receives, demodulates and filters a signal before sending it to the audio card. It's been working in a single board, single core, computer with an audio card ALC888 for months. I occasionally had underrun messages, specially when changing filter parameters. This messages were normally less than 10 and very spread, about every 30 seconds. It didn't cause any noticeable noise or problems. Recently I moved to a better computer with better CPU, 4 cores and a ALC662 audio card. The Python script works fine, with no visible bottlenecks in the processor. However, I now get constant overruns and underruns reported, making the audio noisy. The audio card is able to work correctly when using the speaker-test command so, there isn't a fault in the hardware. It's also capable of running at the required sample rate. Is there any test I could make to understand and fix this issue? Has anyone had a bad experience using this audio card with GnuRadio? Thanks, Murray ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] ALC662 audio card causes underruns and overruns
Wow, 12.04 (though still supported by GNU Radio!) feels ancient. Any particular reason you stick with that? On 28.08.2015 15:09, Murray Thomson wrote: Thank you for your suggestions. The card supports 96 KHz and I'm using hw. I'll try to use plughw. I've solved this problem upgrading to the latest kernel in 12.04 which is 3.13.0-62. Regards, Murray On 28 August 2015 at 13:52, Marcus Müller marcus.muel...@ettus.com mailto:marcus.muel...@ettus.com wrote: Also make sure that the ALC662 also supports the audio sampling rate you're using -- 44100 is the only rate I've been able to use on any platform [1]. Best regards, Marcus [1] http://gnuradio.org/redmine/projects/gnuradio/wiki/ALSAPulseAudio On 28.08.2015 12:31, Jeff Long wrote: Make sure you're using 'plughw:' for the audio device so the driver does resampling (check ALSA docs). Without looking at the flowgraph, I'd guess this is a clock domain problem and your new computer (and audio card) clocks are somehow different than your old ones. On 08/28/2015 04:40 AM, Murray Thomson wrote: Hi, I have a flow graph that receives, demodulates and filters a signal before sending it to the audio card. It's been working in a single board, single core, computer with an audio card ALC888 for months. I occasionally had underrun messages, specially when changing filter parameters. This messages were normally less than 10 and very spread, about every 30 seconds. It didn't cause any noticeable noise or problems. Recently I moved to a better computer with better CPU, 4 cores and a ALC662 audio card. The Python script works fine, with no visible bottlenecks in the processor. However, I now get constant overruns and underruns reported, making the audio noisy. The audio card is able to work correctly when using the speaker-test command so, there isn't a fault in the hardware. It's also capable of running at the required sample rate. Is there any test I could make to understand and fix this issue? Has anyone had a bad experience using this audio card with GnuRadio? Thanks, Murray ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org mailto:Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org mailto:Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org mailto:Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] R820T2 in Gnuradio
Hey, Jan, My only problem is how to start using the R820T2. I already know Gnuradio, but I didn't used it with R820T2. Cheers, Pedro 2015-08-28 11:06 GMT-03:00 Jan Krämer kraemer...@gmail.com: Hey Pedro, if you don't have any experience with GNURadio you should start with the guided tutorials[1]. To use the R820T2 with GNURadio you should build and install gr-osmosdr [2], if you haven't done it already. Cheers, Jan [1] https://gnuradio.org/redmine/projects/gnuradio/wiki/Guided_Tutorials [2] http://sdr.osmocom.org/trac/wiki/GrOsmoSDR 2015-08-28 15:46 GMT+02:00 Pedro Gabriel Adami pedrogabriel.ad...@gmail.com: Hello, I followed some instructions and I installed the files in Gnuradio which respect to R820T2. Now, to start and continue my research, I need some tutorial to teach me to use this device and how to make a communication between Gnuradio and R820T2. Please, can anyone help me to find this? Or maybe you have already used this before. Thanks a lot. -- Cheers, Pedro Gabriel Adami ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio -- Atenciosamente, Pedro Gabriel Adami ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] R820T2 in Gnuradio
Hi Pedro, you got answers to this question yesterday. Was something wrong with them? Where can we pick you up to help you get further? Best regards, Marcus On 28.08.2015 15:46, Pedro Gabriel Adami wrote: Hello, I followed some instructions and I installed the files in Gnuradio which respect to R820T2. Now, to start and continue my research, I need some tutorial to teach me to use this device and how to make a communication between Gnuradio and R820T2. Please, can anyone help me to find this? Or maybe you have already used this before. Thanks a lot. -- Cheers, Pedro Gabriel Adami ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] General_Work Not Executing
Hello All, I recently rewrote the Chat Sanitize and Chat Receiver blocks from the Tutorial module(Example 5) in C++. I did this because I wanted to add an acknowledgment feature into the blocks in order to add some robustness to it(I'm not sure yet if the chat example will lend itself to being robust but it was the starting point I chose). The problem arose when I added an input port to the Text Sanitize block and added an output to the Chat Receiver block and connected them together. Instead of a linear program I now had a loop of a program. I did something wrong because now the Text Sanitize block wasn't outputting anything, so I commented out the input code for Text Sanitize and the output code for Chat Receiver. I went to retest the program to see if it behaved just like Example 5(which it was before I started adding on the acknowledgment bits) but now Text Sanitize wasn't outputting anything still. I tried putting some cout's in the general _work function where the message publishing code is and I have determined that it's not even entering the general_work function. Does anyone have any thoughts on the matter? I must have changed something when I commented out the input portion of the Text_Sanitize code but for the life of me I can't figure out what it is. I have even since made two new blocks to try and redo the functionality of Text Sanitize but the same problem still persists. My code can be found at: https://github.com/loganwashbourne/Thesis.git The juicy files are in the Thesis/OOT/gr-ACK/lib folder. There might be some profanity in the commit messages, it was a stressful day. I appreciate your time, Logan Washbourne Electrical Engineering Graduate Student (Electromagnetics) ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] performnace monitor runtime usage to the whole system
Daer Marcus, Thank you for your detailed answer. Now I feel I am getting to it... But, not fully, yet :) What I've said 'one' in the previous post is, you can understand with the figure: http://i.imgur.com/QG5uryH.png I've posted the same figure in another thread some days ago. Anyway, 'one' I meant is, the total sum of percent runtime. That is one and should be. Regards, Jeon. 2015-08-27 2:09 GMT+09:00 Marcus Müller marcus.muel...@ettus.com: Hi Jeon, But I don't think that GNU Radio uses 100 percent (= one) of CPU capability. Well, that obviously depends on what you *do *with GNU Radio. Generally, GNU Radio scales pretty well, so I'm going to reply with: GNU Radio tries to consume as much CPU as possible. There's limiting factors, mainly RAM access and IO that limit how much CPU can get consumed. As you seem to be running a receiver: There's the upper limit on how much CPU can get used of samples coming in. You can only process as much signal as there is. Also, things that are out of the scope of the GNU Radio process tend to play an important rule here: The kernel has to talk to your radio hardware, etc. I'm not quite sure what you refer to with one; do you mean the 1 that tools like top would display (namely: one fully occupied CPU core according to a more or less useful statistic; single processes can in that metric actually have CPU loads 1)? In order to calculate runtime usage of each block, therefore, it can be done by multiplying usage of GNU Radio process. No. GNU Radio is a heavily multi-threaded architecture, so each block runs in its own thread. Assuming you have a multi-core CPU, multiple threads will run at once; one core of your CPU might be 100% occupied by the GNU Radio block thread(s) running on it, whereas another is only 80% busy etc. This does not allow direct mapping of percentage of CPU load to actual time. However, the performance counters offer exactly what you seem to need: The percentages your looking at are computed from the microseconds that each block spends in its work function. So just look at these total times. I think it would be interesting to hear what you want to do, maybe we have an idea how to measure what is of interest to you. Best regards, Marcus ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] What factor determines input_item size (ninput_items)?
I am testing my OOT module in various condition of different machines. A certain block implementing a state machine requires a certain number of items or more. Thus, I've stated it in forecast(): https://gist.github.com/gsongsong/9ba1cb974a57a0861678#file-forecast-my_block-cpp In general work(), the block determines how many items it should be consume: https://gist.github.com/gsongsong/9ba1cb974a57a0861678#file-general_work-my_block-cpp With these codes, it works find with my own machinie. Ubuntu 14.04, 2 CPUs and 4 GB RAM allocated virtual machine. The host has i7-3770 and 16 GB RAM. But it fails on machine that my school gave to me for educational and research purposes. I can't tell you the exact spec. of the machine, but it apparently has a poor CPU and a lower memory space. Do these difference on machines' specs affect on ninput_items? I think they have a certain relation to each other... since GNU Radio scheduler allocates available memory over all blocks...? If so, can it be resolved if I manually set a larger memory/buffer size to GNU Radio? (If my memory is correct, I remember there's a configuration file to do it...) Regards, Jeon. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] What factor determines input_item size (ninput_items)?
Hi Jeon, What factor determines input_item size (ninput_items)? these are two things: the input item size is the size of a single item, and ninput_items is the amount of items that your (general_)work call sees. You are referring to the second thing: Consider this flow graph: A - B - C A is the upstream block (e.g. USRP source), B is your block, and C is a downstream block (e.g. Vector sink). ninput_items is determined by how many samples are available. Your block B has no influence on it; whenever the upstream block A finishes doing its (general_)work, GNU Radio updates the number of items available in the buffer between A and B. It then asks B whether it wants to work on this amount of input samples. I see your forecast method, and it seems to do the right thing: If your block is in the SYNC state, to output anything, it needs 480 items. If there's no 480 input items, GNU Radio won't call your general_work, usually. You should try printing ninput_items, to see if that's correct. Now, your block has two input streams. If they are somehow related, timing and buffer sizes might actually lead to a deadlock situation. Can you give us an overview over the whole flowgraph? Best regards, Marcus On 28.08.2015 19:00, Jeon wrote: I am testing my OOT module in various condition of different machines. A certain block implementing a state machine requires a certain number of items or more. Thus, I've stated it in forecast(): https://gist.github.com/gsongsong/9ba1cb974a57a0861678#file-forecast-my_block-cpp In general work(), the block determines how many items it should be consume: https://gist.github.com/gsongsong/9ba1cb974a57a0861678#file-general_work-my_block-cpp With these codes, it works find with my own machinie. Ubuntu 14.04, 2 CPUs and 4 GB RAM allocated virtual machine. The host has i7-3770 and 16 GB RAM. But it fails on machine that my school gave to me for educational and research purposes. I can't tell you the exact spec. of the machine, but it apparently has a poor CPU and a lower memory space. Do these difference on machines' specs affect on ninput_items? I think they have a certain relation to each other... since GNU Radio scheduler allocates available memory over all blocks...? If so, can it be resolved if I manually set a larger memory/buffer size to GNU Radio? (If my memory is correct, I remember there's a configuration file to do it...) Regards, Jeon. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] performnace monitor runtime usage to the whole system
Agreed :) On 28.08.2015 18:16, Jeon wrote: Daer Marcus, Thank you for your detailed answer. Now I feel I am getting to it... But, not fully, yet :) What I've said 'one' in the previous post is, you can understand with the figure: http://i.imgur.com/QG5uryH.png I've posted the same figure in another thread some days ago. Anyway, 'one' I meant is, the total sum of percent runtime. That is one and should be. Regards, Jeon. 2015-08-27 2:09 GMT+09:00 Marcus Müller marcus.muel...@ettus.com mailto:marcus.muel...@ettus.com: Hi Jeon, But I don't think that GNU Radio uses 100 percent (= one) of CPU capability. Well, that obviously depends on what you /do /with GNU Radio. Generally, GNU Radio scales pretty well, so I'm going to reply with: GNU Radio tries to consume as much CPU as possible. There's limiting factors, mainly RAM access and IO that limit how much CPU can get consumed. As you seem to be running a receiver: There's the upper limit on how much CPU can get used of samples coming in. You can only process as much signal as there is. Also, things that are out of the scope of the GNU Radio process tend to play an important rule here: The kernel has to talk to your radio hardware, etc. I'm not quite sure what you refer to with one; do you mean the 1 that tools like top would display (namely: one fully occupied CPU core according to a more or less useful statistic; single processes can in that metric actually have CPU loads 1)? In order to calculate runtime usage of each block, therefore, it can be done by multiplying usage of GNU Radio process. No. GNU Radio is a heavily multi-threaded architecture, so each block runs in its own thread. Assuming you have a multi-core CPU, multiple threads will run at once; one core of your CPU might be 100% occupied by the GNU Radio block thread(s) running on it, whereas another is only 80% busy etc. This does not allow direct mapping of percentage of CPU load to actual time. However, the performance counters offer exactly what you seem to need: The percentages your looking at are computed from the microseconds that each block spends in its work function. So just look at these total times. I think it would be interesting to hear what you want to do, maybe we have an idea how to measure what is of interest to you. Best regards, Marcus ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] FSK receiver
Hi Hoang, Yes it's a problem with your design. You have 2 Msps feeding into an audio sink that probably goes up to 48 ksps. You need to change your sample rate from 2 Msps to a rate your sound card supports. I would target one of the default rates you can select from the audio sink. You can use polyphase arbitrary resampler block with the proper resampling ratio 2M/48k entered leaving the taps blank and the other parameters to default. Hope that helps, Rich On Fri, Aug 28, 2015 at 2:19 PM, Hoang Nguyen Tran hoangn...@gmail.com wrote: Dear all, I have just built a FSK receiver aim to receive Cubesat data with FSK modulation with 9600 baud rate, below is my flow graph. I have just tested it with usb dongle RTL-SDR, however when I'm using audio sink, I received O (overrun I think) continuously . Does it have anything wrong with my set up ? samplerate 2M cut off freq 9600 transition 4800 I really appriciate for any comment on my FSK receiver flowgraph, I am a newbie :) Thank you and best regard, Hoang -- -HoangNT- PhoneNo : +841654248782 Skype : hoangastro FB : https://www.facebook.com/kenshin.rorouni ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
