How to get A3 red sigil?

[MacAnny]

Does anybody know how to get the A3 red sigil? Drives me crazy...

[Aerisana]

"you have been given all the tools you need to comlete your task."
"If what you are doing is not working, Try it a different way"

[*Evil Vasile]

Hint: You can pick up the Jammer when standing above it

I don't want to spoil too much, so I guess if that didn't help maybe you should post what exactly you're having trouble with.

[checkers_of_shalmone]

I spent around 5 minutes, maybe? on the second step of this problem as well, so I should give hints there too:

Vague: Backtrack.
Related: Use your Jammer and free a bomb.
Direct: Jam the door you opened first again, and direct it to the turret.

[MacAnny]

"Pick up Jammer from above", that did it... thanks for the tip!