does anyone know how rtl_test -p works (or am i going to have to read the src code ;-)
I ran it for 60s as follows: ben@esroe-5:~/rtl-sdr$ rtl_test -p 60 Found 1 device(s): 0: Realtek, RTL2838UHIDIR, SN: 00000001 Using device 0: Generic RTL2832U OEM Found Rafael Micro R820T tuner Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6 Sampling at 2048000 S/s. Reporting PPM error measurement every 10 seconds... Press ^C after a few minutes. Reading samples in async mode... real sample rate: 2048274 current PPM: 134 cumulative PPM: 134 real sample rate: 2048194 current PPM: 95 cumulative PPM: 114 real sample rate: 2048271 current PPM: 133 cumulative PPM: 120 I assume the current is the value computed from the last 10s and the cumulative is a 'running' mean. I guess the idea is that you use the cumulative ppm as an arg when running rtl_fm, rtl_power or whatever other app you are using (if it has the ability to apply a correction to the tuner)? I think it may have crashed as it only reported 3 readings, I have noticed that my dongle seems a bit temperamental, I often get errors like this: Using device 0: Generic RTL2832U OEM rtlsdr_write_reg failed with -1 Resetting device... rtlsdr_write_reg failed with -4 rtlsdr_write_reg failed with -4 rtlsdr_write_reg failed with -4 rtlsdr_write_reg failed with -4 rtlsdr_write_reg failed with -4 rtlsdr_demod_write_reg failed with -4 rtlsdr_demod_read_reg failed with -4 rtlsdr_demod_write_reg failed with -4 rtlsdr_demod_read_reg failed with -4 -- best regards, - ben
