How to drive relays?

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http://forum.allaboutcircuits.com – Hello guys, I am quite newbie in electronic and more or less self-taught in this area. I would be happy if you take a look into these schematics with Arduino: http://remoteqth.com/hw/band_decoder_sch.png I have project completed and digital outputs from Arduino send signal through resistor and led diode, optocoupler and NPN transistor. There are 12 open collector outputs and I want to drive 12v relays (about 30ma, 360 ohm coil resistance) on the SV2 outputs. I have applied +12v to the relay, put diode over coil and connected specific output to other side of the coil but relay doesn't (Embedded)