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--></style></head><body lang=EN-US link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi Marcus and thanks for your reply.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>>Your video is about 13 minutes longer than I'd like – can you pinpoint<o:p></o:p></p><p class=MsoNormal>>at which time in that video your transmission stops?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>You can watch this <a href="https://www.youtube.com/watch?v=G0tjzPHFFA8">video</a> between 7:00 & 8:00 to observe the breakdowns.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>>As usual, debugging on the side of the observing party might very well<o:p></o:p></p><p class=MsoNormal>>be helpful here. Figure out whether the program halts (a software<o:p></o:p></p><p class=MsoNormal>>debugger, e.g. gdb, would be the appropriate tool), the USB transfers<o:p></o:p></p><p class=MsoNormal>>stop (wireshark might be helpful here), or whether just something<o:p></o:p></p><p class=MsoNormal>>happens inside the device while the computer and software happily<o:p></o:p></p><p class=MsoNormal>>continue to work. Observing the spectrum might help.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>You just gave me a good point to start debugging this issue! Actually I don’t have a RTL-SDR or anything else in hand right now to observe the spectrum but I will do the tests soon.<o:p></o:p></p><p class=MsoNormal>--------------------------------------------<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hi Steve, did a great job!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>>This will happen if the host cannot supply enough data to the device,<o:p></o:p></p><p class=MsoNormal>>you need to use a lower sample rate in this case, or get rid of<o:p></o:p></p><p class=MsoNormal>>a hypervisor like VMware, as is the case in this video.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I tried fl2k_fm both in VMWare and in GNU radio live image booted from a flash drive and in both I had the problem. and why should I use a lower sample rate when my system can handle the samples well? (take a look at attachments)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m using VMWare Workstation Pro (Version: 14.1.2 build-8497320) on a brand new ACER laptop (Model: Aspire A715-71G-71Y3) running Windows 10 Pro 1803 (Build: 17134.112) with 16 gigabyte RAM and an Intel Core i7 7700HQ CPU. The USB host controller is <u>Intel(R) USB 3.0 eXtensible Host Controller - 1.0 (Microsoft) </u>witch I believe it can handle up to 157 MS/s. all drivers are updated. <o:p></o:p></p><p class=MsoNormal>However, I didn’t see anything wrong with virtualization except that the maximum achievable sample rate was a little lower than the GNU radio live booted from flash drive. Except for this, I didn't encounter by anything.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>>There seems to be a 'frame loss' mechanism to detect this in through an<o:p></o:p></p><p class=MsoNormal>>interrupt transfer, but I haven't implemented this yet and have no idea<o:p></o:p></p><p class=MsoNormal>>if this works with disabled synchronization.<o:p></o:p></p><p class=MsoNormal><span style='font-family:"Arial",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal>Looking forward to the results!<o:p></o:p></p><p class=MsoNormal>And don’t mind asking me for a helping hand. I’ll do my best to help this project.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I was reading the comments below <a href="https://www.rtl-sdr.com/running-osmo-fl2k-on-vmware-workstation-pro">this</a> post in rtl-sdr.com blog and I saw a user who had the same issue mentioned something that might be useful:<o:p></o:p></p><p class=MsoIntenseQuote><span class=MsoBookTitle><span style='font-style:normal'>Of futher note (hopefully someone from osmocom will see this) the bug where the broadcast intermittently ceases in fl2k_fm under both an ubuntu virtual machine and directly ran as a windows exe seems to have something to do with cpu affinity and / or process priority – generally it starts spitting out the underflow message on stdout then the signal drops out and the process requires a restart.<span lang=AR-SA dir=RTL><o:p></o:p></span></span></span></p><p class=MsoNormal>Regards,<o:p></o:p></p><p class=MsoNormal>Sajjad<o:p></o:p></p></div></body></html>