1 - Broke
When coming from the Fast Travel Point, the Typhon Log is behind a closed door in a room.
You can access this room from the next open area.
There is a staircase going up to this room.
2 - Skag CEO
Remember the big fiery turbine you need to turn off in the story?
There is a passage right before you jump over to the turbine that leads to this Typhon log.
3 - "Ambush on Skywell-27"
This Typhon Log is right after the Incinerator on Level 2 of the map.
The map above shows, where you have to take a ladder up to reach the Typhon Log.
From up there you just jump over to the Typhon Log.
TYPHON DEAD DROP
The Typhon Dead Drop is in the area where you access the Data Center / Server Room.
From here, there is a staircase going directly to the Dead Drop.