Head towards the back of the turian camp and follow the waypoint to the left and out the silver barricade. The tower will be shortly ahead and to the right. Liara will promptly point it out. Shortly after, a wave of husks will rush your position from the front. If you are playing a Vanguard, take out your Shotgun and get to work. Otherwise, order your squad in flanking positions and lure them through the middle. Let your squad unload on them from both sides while you attack from the front.
Approach the tower and examine it. You will have to make a choice here. You can either send Liara to fix the tower, or send James. Liara is much more technically adept than James, so send her, as it will get done faster. You will now have to defend the comms tower from waves of enemies as they try to climb up behind Liara. Physically strong classes will want to take a more direct approach to this battle. If you’re playing as a Soldier, Vanguard, or Sentinel, you can simply strafe around the tower and use your heavy-hitting weapons, like Shotguns and Sniper Rifles, to pick off the husks as they come to you. If you get crowded, hold down the B button for a charged-up melee attack to give yourself room to breathe.
Alternately, if you are playing as a Biotic or Tech user, you should focus mainly on taking the husks out before they can get anywhere near you. Use Singularity to slow the approach of as many of the creatures as you can before using Warp and small-weapons fire to eliminate those who weren’t caught in the radius of your attack. Then pick off those left behind by your Singularity.
The enemies will approach from both the left and right. Cover one side yourself, and leave the other to James. Liara should finish the repairs in no time, and you will have to head back to the camp to inform the General of your victory. Along the way, more hoards of husks will run out. The meteor-like projectiles falling to the moon’s surface will spawn groups of them. Use a similar strategy as before to kill them. As you return to the camp, the General will inform you that the comms tower is back online. Head back into the camp from the way you came, and speak with General to initiate the next phase of this quest.