Thanks, "nmiller"!
Unfortunately, all I have are the electronic extensions. With the extremely-light usage from (at most) 5 people remaining in our "temporary" facility, I can't justify further exploration. This was in the category of "nice to have" rather than "need to have". After this system becomes surplus (again!) and I scarf it up, maybe I can convince its next owner to let me experiment.
As I wrote in the Toshiba forum, the whole thing started with wanting to change one feature of one extension and my curiosity took over. None of this was a waste of time or effort, as I've learned from the process and found some really great folks on this very interesting forum!
Cheers,
-Michael Shovan, CBTE
(SBE Certified Broadcast television Engineer)
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