Sdr
this page is intended to guide you through software defined radio. cubicsdr is a SDR application that has few requirements and is known to work well.
add rtlsdr useflag to make.conf
emerge cubicsdr
gpasswd -a $USER usb #users need to be in the usb group to control the sdr dongle.
radio antenna length measured to the frequency and divided in half provides high gain, and strong signal reception. antenna lengths work in 1/2s 1/4ths 1/8ths and between, many cb antennas run something like 5/8ths length or 1/4 wave 109 inch whip antennas. there are many types of antennas, parabolic dish antennas provide long distance narrow signal beams good for point to point such as long distance wireless network connections.
145.800 is the international space station frequency.
rtl-sdr blog sells a kit for 30 dollars with a dipole antenna, with two antenna element length sets, and dongle on amazon. this is a good starting point to getting into listening to FM, AM, amateur radio, and CB. the kit is found here:
https://www.amazon.com/dp/B011HVUEME/ref=cm_sw_em_r_mt_dp_U_4NUnEb6S5H0QH