I have this example circuit on my workbench:
If I remove the RLOAD=1K resistor, then the output signal gets distorted.
Yellow is Node1 and blue is node2. With R load:
Without R load:
It is not easy to read from the picture but the lower part of the square signal starts at 600mV (one junction) and slowly goes down to about 50mV. Here is it zoomed:
The same thing happens at node1 too, but I'm less concerned about that. I wonder why there is distortion when there is no load?