Young’uns forget after WW2 a fair percentage of the male population in the UK were trained to kill. The rest including women served in many public and military jobs including code breaking.
This is of course, conjecture but Phyllis seems quite adept at putting the machine to work crunching numbers and knows discrete electronics. The difference between single and dual potentiometers, capacitors.
A tell is “electronic gadget.”
According to the YT comments, Phyllis passed away in 2020. It’s conceivable Phyllis was almost 60 here. Easily old enough to have lived through WW2.
