Who voiced Donald Duck in the episode where he gets a human voice?

It's one of the older episodes, where he's trying to sell brushes door-to-door and ends up buying these voice pills.

There's another episode where Donald finds an exact copy of himself (voiced by the same actor) and he convinces the guy to pose as him (Donald) to woo Daisy.

Both of these are in a compilation of older videos on YouTube, so I don't have names.

I'm just curious if the guy who does that voice is the same guy who does Donald's regular voice.