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Leif Asbrink leif at sm5bsz.comHello Frederic, Each sample is I and Q with 8 bit each. That is 2 bytes. When you sample at 2.048 Ms/s you get 4096 bytes/ms so your observation that it takes 2 ms to fill the buffer is fine:-) The buffer size is not critical. In my project Linrad it is a user parameter because small buffers may be useful for radio amateurs who want a small delay from antenna to loudspeaker when doing two-way communication while larger bufers may be helpful on slower computers. I tried buffers from 2048 bytes to 524288 without errors on a fast computer. You are not doing anything wrong:-) Leif > Hello, > > I am testing a DVB-T USB key including the Elonics E4000 chipset and I want to check the sampling rate of this card. > I set up the sampling rate at 2.048 Ms/s (rtlsdr_set_sample_rate), and my storing buffer is 8*1024 bytes, so I expect receiving 1024 I/Q samples every 500 microseconds. > I am using the rtlsdr_read_async function to read the samples. > Unfortunately the loop in my program indicates that 8*1024 bytes are read every 2 milliseconds. > I am using the gettimeofday function to measure the time in microseconds. > Does this result mean that the best I can do is to read some samples every 2 ms at 2.048 Ms/s. This would mean that I am missing 1.5 ms of signal. > Is that correct or I am doing something wrong ? > > Thanks for your help. > Frederic > > > _________________________________________________________________________________________________________________________ > > Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc > pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler > a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration, > France Telecom - Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci. > > This message and its attachments may contain confidential or privileged information that may be protected by law; > they should not be distributed, used or copied without authorisation. > If you have received this email in error, please notify the sender and delete this message and its attachments. > As emails may be altered, France Telecom - Orange is not liable for messages that have been modified, changed or falsified. > Thank you. > >