This quest involves collecting weapons for one of the Sentinel High Commander Fielding. To find him and start the quest you'll have to head to the Sentinel's Tower Research Base (2700,3500) in Wailing Wastes. You can get there fairly easily if you use the Wailing Wastes Whom-Pah in Athen.
It can be found in the far North East of that zone, just past the crater lake.
You will find High Commander Fielding at the top level of the base at the start of the upper row of barracks.
If High Commander Fielding is not around, it means he just made a quick trip to resuply. Just hang around for 5 minutes and he'll return.
He will tell you that the sentinels are on the verge of constructing new upgraded Towers, but some integral parts are still missing. They can't delay development, as it will lead to Omni-Tek constructing the first upgraded Tower. The consequences of that would be disastrous. He will send you on a quest to find the components they need. Tell him that you are willing to do so and you will get the mission for the quest. He will give you a Dimension Crushing Storage Device.
These weapons drop off the Omni-Tek Defense Patrollers, Defense Guards and Scouts wearing energized armor in Avalon. They can be found in and around either Omni-Tek Bases in the area, they are over level 150 and are located inside and around the perimeter of each heavily defended base.
I advise against pull them out without a strong team since there are level 220 Sergeants at each base. Your best chance with a reasonable chance of success on a hill near the Main Omni-Tek Base (2110, 1340). There are also guard around at the bottom of the hill allowing you to have a good number of targets.
The hill will have more than enough guards for you to get the weapons you need, there is a level 160 Sergeant Harry at the top that is stronger than the average guard, he has no weapon so he will be using martial arts against you.
It is likely that during all the fighting you will find a few Clan Bravery Tokens on the guards which is an extra bonus while doing this quest.
At this point he will ask you if you would like one of the "Tower weapons" which and give you a A Note to Supply Master Smug, depending on which of the weapons you have collected.
Note that this is completely optional and only required if you wish to build one of the Advanced Notum Wars Turrets.
Currently the turrets you are given for the M150 N.A. Booster Edition are not ingame.
If you wish to get one of the tower weapons, head North-West to the Supply Master Smug.
Below is the list of tower weapons you will receive depending on which weapon you have collected:
Supply Master Smug also has a quest for you to perform if you are up to it.
Note: This quest is mostly used to 'farm' tokens. It is common for people to actually sell bags of Fine Tuned Westinghouse IM-50 Plasma Burners, they are known in the community as 'token guns' or 'token bags'. This is due to the large number of people with Shadowlands expansion who skip Rubi-Ka missions. In the Shadowlands there is no way to earn tokens.