Saw "The King's Speech" yesterday and can highly recommend it to anyone interested in 1930's era broadcast radio studio and control room equipment.
There are wonderful microphones, mixing equipment and switchroom gear presumably for an early BBC World Service. There's also a wonderful scene with an announcer preparing to speak, complete with gargling and throat spray action.
Aside from this interesting dimension for me, it's a wonderful film for the whole family, wonderful photography and masterful performances.
These are clipped from the trailer, hope that's ok.
Looks like the levels going out to Australia are a bit low.