This episode shows the transformer as obtained, and includes some initial dismantling and examination.
Claimed to be 2 kVA, and probably 30-40 years old.
This item was obtained as working, and was demonstrated connected to 240V AC.
A few basic checks are done, including continuity between all of the transformer terminals.
As this is an autotransformer, it only has a single winding, there is no isolation between any of the terminals.