Doctor Who : Where classic doctor's announced before regeneration?

I've been a classic who fan for years but sadly was born the year the show cancelled so I never got to witness it as it aired.

With the internet it's hard to have surprises in the show. I was just wondering how regenerations got handled in classic who? Did the audience ever know a regeneration was coming or did the show always keep it a secret?

As I recall, it was always known. Typically, "the new Doctor Who" would be announced on the news.

This whirlpool's got such seductive furniture
It's so pleasant being drowned

i wouldn't like to have a regeneration sprung upon me, but I would love to be able to live in a vacuum enough that i don't know who the new actor will be until it happens on screen

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The mans tongue didnt come through customs!

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Oh I'd love a sudden regeneration. Problem is when we know the doctor is safe then we know he'll survive.

Yeah I remember seeing articles announcing Peter and Sylvester's casting

https://soundcloud.com/coin-sides

New song "Breathless Love"

Tom Baker has talked about how he was between acting jobs and working a construction site when the news about his casting appeared in the paper. Baker likes to tell how his mates on the job came up to him and asked if it was really him who was going to play the Doctor.

mf

I know that, in spite of the poets, youth is not the happiest season"