Once installed, a red light will flash on the top of the device while it is working. It will slowly grow in size as the resource is harvested. Once full, the light will turn green.

When installing an AMU, be sure to place a Save Beacon nearby, or it will be hard to locate later.

A fully charged device will harvest a maximum of 250 units over a time period of roughly 60 minutes.

The device can not be picked up but it can be deleted for a full refund like any other base item when in construction range of a base.

Workarounds for the bug that causes the AMU to collect the wrong resource: Delete and re-build it. This is free if it is built within the boundary of a base you own, but not possible otherwise.
When collecting the resource from the AMU leave behind 10 of whatever the item is and it should not change what it collects.
Only 5 AMUs can be placed in any local area.