This machine was first installed at the Reading Railroad's Pottsville Junction Tower in Pottsville,PA.  It was later moved into the Schuylkill Haven, PA. passenger depot.

This machine controlled the following territory:

        Main Line - Port Clinton to Pottsville
        Little Schuylkill Branch - Port Clinton to East Mahanoy Junction ("BARNS")
        Schyulkill Valley Branch - Pottsville to Tamaqua
        Mahanoy & Shamokin Branch - East Mahanoy Junction to Buck Mt.
        Catawissa Branch - East Mahanoy Junction to Lofty

This machine was very interesting in that it was built by General Railway Signal Company and controlled both a GRS Type K code system and a US&S Type 506 Time Code system.
The GRS Type K code system was used between Port Clinton and Pottsville which included "Clinton","Stone", "Dock" and "Potts" interlockings on the Main Line and "Broad", "Molino", "Sand", "Ring" and Myrtle" interlockings on the Little Schuylkill Branch.  The US&S 506 Time Code system was used from Tamaqua to Buck Mt. and included,"Tamaqua","Barns","Mahanoy Tunnel" and "Haucks" interlockings.

"Code chart for the General Railway Signal K Code portion of the control machine"
"Code chart for the Union Switch & Signal 506 Code portion of the control machine"

As time passed,remote interlockings were retired and at the end the only thing left operating was "Potts" and "Clinton".  This is why you see a lot of black electrical tape covering the track model.  Parts of the machine were utilized at "R" Tower in Rutherford for signaling projects on the Lurgan Branch under Conrail.  The machine was finally retired in 1983 when the signal system was removed entirely between Belt Line Junction (north of Reading) and Pottsville, PA.
The remains of the machine presently on display at the Railroad Museum of Pennsylvania in Strasburg, PA.and is owned by the Reading Company Technical & Historical Society.