Thank you very much for you kind help.I have done the whole process with SDR# ,VB-Audio cable and DSD+ and it works well,but I need the raw data just after demodulation saved in some type of file on my computer i.e. the raw 0 and 1 data. The DSD+ has decoded the raw data and then displayed them on the DSD+ channel activity. I want to learn the P25 protocol with the raw o and 1 data from which we can find something like frame synchronization . If any further suggestions ,pls let me know. Thank you again