https://www.youtube.com/watch?v=_Zq53wGd34E

MAME now supports emulating an East German numbers station speech generator, if that's something you need to have handy for any reason

MAME Showcase Gerät 32620 (Sprach/Morsegenerator): German speech

YouTube
@revenant More on Gerät 32620, the East German numbers station voice synthesiser now emulated in MAME:
https://www.cryptomuseum.com/spy/owvl/32620/
It appears to be based on (an Eastern-bloc knockoff of) the Z80, and the UI uses more English words than I expected an Eastern-bloc spy device to. (Perhaps German words take up too much space?)
32620