Left side there is diode D5 (black) that needs to be
shorted to feed power from powersupply-jack J1 to
USB-uplink UP1.

Note that there is no other regulator or protective device than just a 2A-polyfuse F1, the voltage from power-connector is fed "directly" to the four downlink-ports. So you mustn't use a powersupply with more than 5.0V, or you may smoke up FR PMU chip!