Method for testing one or more of a group of radio frequency (RF) data packet signal transceiver devices under test (DUTs) with reduced signal interference from the remaining DUTs. A tester broadcasts a signal containing power control instructions about uplink signal power characteristics for communication with the tester. For example, for the LTE 3GPP standards, such characteristics could include power ramping step size, preamble initial received target power or maximum number of preamble transmissions for uplink signals transmitted from the DUTs. Following initiation of communication between the tester and one or more DUTs, the tester broadcasts a signal containing power control instructions to instruct the remaining DUTs to transmit any future signals with different uplink signal power characteristics. For the LTE 3GPP standards, such different characteristics could include reduced power ramping step size, reduced preamble initial received target power or reduced maximum number of preamble transmissions for uplink signals.