No that last beacon was definitely my fault
completely forgot it was in the open. (it seemed like a nice hidden spot
but oh yeah, it's one of those maps. I tried to put a few of them in places under cover so you wouldn't have to parachute in on them.
What's the consensus on where they should be placed? Somewhere close to the flags or somewhere out of the way, away from the action so that you can sneak back in?
You have to take into consideration of 3 things regarding the beacon:
1)Location: The location should never be too far away from the flag, but never so close to the point where it would start catching the enemy's attention (avoid hot zones).
2)Visibility: Beacons should not be placed at areas where there is full visibility (ex: open street/rooftop = bad idea.) If you don't have that option, try to make your own (shoot out lights in metro's subway car or place it behind fires.
3)Sound: Beacons should be placed in areas where it would be difficult for the enemy to hear or an area where people usually won't pass b. This doesn't necessarily mean it has to be far away. You can abuse the sound of the m-com or a buzzing high voltage box to null the sound.
So take canals for example:
At one point you placed a beacon right next to the crate near A flag.
That beacon instantly got destroyed once a tank arrived.
It would have been useless even if it lasted as
a) person who spawn on it will have to parachute in.
b) the beacon is dead obvious to anyone with good eyes/ear
c) It's in a dead obvious high traffic area.
So where could you have better placed it?
Well, in front of A there are a bunch of crates. Some of these crates are stacked to two story tall. Some of those higher crates have openings that are dark, give a top down view of A and is "indoors". We also know from the map design, that the area is generally not a hot zone (just outside of the edge of the ABC triangle.) So most people won't be spending their time hanging around trying to find the beacon.
Alternatively, the loading boats near A is also a good choice. They are generally outside of the area of attention, have some what of a block of visibility (lower terrain than most of the map) and can spawn people indoors.
Now, I often see people place beacons in the yellow crate right next to A or the red crate right in front of the flag. Those are bad choices because people will check those places first + the sound is obvious.