30 (10x3) LEDs drawing probably around 20 mA each will require a 600 mA power supply
It is with external power. The grey wire connecting to the "9V" pin
3. just out of curiosity, insted of putting a resistor in every led, can't i put "high" resistor at the emmiter of each NPN? i mean between GND and Collector&Base "junction".
(5V - 0.7 - 3.3)/0.02 = 50 ohm
The barrel jack connector output goes to a reverse polarity protection diode which then connects to the Vin header pin, and then feeds the 5V regulator and shows up at the 5V header pin