  The Baryon acoustic oscillations from Integrated Neutral Gas Observations
(BINGO) telescope is a new 40-m class radio telescope to measure the
large-angular-scale intensity of Hi emission at 980-1260 MHz to constrain dark
energy parameters. As it needs to measure faint cosmological signals at the
milliKelvin level, it requires a site that has very low radio frequency
interference (RFI) at frequencies around 1 GHz. We report on measurement
campaigns across Uruguay and Brazil to find a suitable site, which looked at
the strength of the mobile phone signals and other radio transmissions, the
location of wind turbines, and also included mapping airplane flight paths. The
site chosen for the BINGO telescope is a valley at Serra do Urubu, a remote
part of Paraiba in North-East Brazil, which has sheltering terrain. During our
measurements with a portable receiver we did not detect any RFI in or near the
BINGO band, given the sensitivity of the equipment. A radio quiet zone around
the selected site has been requested to the Brazilian authorities ahead of the
telescope construction.
