*>>> Are you sure?* Yes.
For the skeptics: ~$ rtl_fm -f 89000000 -R -s 1000000 -g 0 - | baudline -stdin -samplerate 1000000 -quadrature -flipcomplex -channels 2 -format le16 Found 1 device(s): 0: Realtek, RTL2838UHIDIR, SN: 00000013 Using device 0: ezcap USB 2.0 DVB-T/DAB/FM dongle Found Rafael Micro R820T tuner Oversampling input by: 2x. Oversampling output by: 1x. Buffer size: 4.10ms Tuned to 89500000 Hz. Sampling at 2000000 Hz. Output at 1000000 Hz. Exact sample rate is: 2000000.052982 Hz Tuner gain set to 0.00 dB. Result: https://dl.dropboxusercontent.com/u/102802145/baudline0dB.jpg ~$ rtl_fm -f 89000000 -R -s 1000000 -g 30 - | baudline -stdin -samplerate 1000000 -quadrature -flipcomplex -channels 2 -format le16 Found 1 device(s): 0: Realtek, RTL2838UHIDIR, SN: 00000013 Using device 0: ezcap USB 2.0 DVB-T/DAB/FM dongle Found Rafael Micro R820T tuner Oversampling input by: 2x. Oversampling output by: 1x. Buffer size: 4.10ms Tuned to 89500000 Hz. Sampling at 2000000 Hz. Output at 1000000 Hz. Exact sample rate is: 2000000.052982 Hz Tuner gain set to 29.70 dB. Result: https://dl.dropboxusercontent.com/u/102802145/baudline30dB.jpg GQRX, LNA gain = 0dB Result: https://dl.dropboxusercontent.com/u/102802145/gqrx0dB.jpg GQRX, LNA gain=30dB Result: https://dl.dropboxusercontent.com/u/102802145/gqrx30dB.jpg It's clear rtl_fm does not set any gain to the r820t tuner
