Reply #4: Thanks for that!

[John Doe II]

The general idea of this thread is simply to clarify who used when what kind of telephone in order to make the discussion more precise and avoid generalization that don't help anybody.
Thanks a lot for all your technical input. I didn't know that. What I know is that all ingenieurs I know simply raised eyebrows to the possibility of the calls. And we have two examples of calls that got disconnected right away. Yet, neither Burnett nor Britton got ever disconnected. On the other hand Bingham got disconnect although using an airphone (at least this is what he said).
In any case: I believe we have all data we need in order to answer the question if theses calls would have been possible.
Btw: If you read my threads about the content of the calls you'll see what I think about them. They don't fit together. Not two calls bascially fit together. And each one has way too many contradictions in itself.