I was able to use the gallery cab car's railfan window to good effect taking pictures of KEDZIE interlocking, TOWER A-2 at Western Ave and the semaphores at Lake Street interlocking right before the Chicago Northwestern Station.
Anyway, there are quite a lot of photos and you can see them all here.
Green Line train a Wabash with a Boeing 2400 series car #2501.
Patriotic 2400's are still running on the Green Line with #2530.
Rapid transit grade crossing abound at Cicero. The green marker lights indicate that the crossing protections have activated.
Interesting platform configuration at Cermak.
Here is a shot I got of a standard CTA cab signal display. The illuminated line grows upwards as maximum permitted speed increases. The three color lights at the left will display red for a Stop, Yellow for any speed below 55mph and green for 55 or 70mph.