Has there ever been a hybrid pantagraph and trolley pole operation before? The main differences I know between the two are that with trolleys you don't have to do as much prep work and can mostly just string up wire, except when it comes to turnouts where things get a little more complicated and you have to set the wire frog just right. With pantagraph operations you have to have the wires relatively taught and zigzagging so as not to wear a notch in the carbon shoe. Unlike trolley however turnouts are fairly straightforward.

San Francisco, California; Pittsburgh, Pennsylvania; Boston, Massachusetts; and Suburban Philadelphia, Pennsylvania all had it in the early1980s while converting or getting new cars. San Francisco still has both under the same wires, as some of its older trolleys are still being used and sharing some wires with the new ones. Sam Diego, California may have had it in the early 1920s.

Sacramento Northern had both on their steeplecabs.

On a pantograph operation, it is crucial that the trolley wire for a turnout be at the same height as the wire on the main line, and NOT hanging down in the span leading to the frog.

If the branching wire is low and a mainline train is approaching the frog in a diverging move, no problem.. HOWEVER, if a mainline train approaches the frog in the converging direction, the pantograph can run above the low-hanging branch line wire and hit the frog.

We operate pole and pan cars sharing wire at National Capital Trolley Museum.

~Wesley

Lisbon, Portugal operates pan and pole, but I don't think on the same wire segments.

Danish tram museum operates pan and pole over the whole route.