Hi
My corrections for Poland
Dial tone is continuous but second type is with cadence 0.975 on 0.05 off . ( like Brazil )
This tone is used, for example, if an extension have active direct diversion or voice mail.
Number unobtainable tone like in Austria frequency 950/1400/1800 cadence 3x0.33 on 1.0 off This tone is used to inform that dialing number is invalid, (vacant ) some times with announcement
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If anything can go wrong, it will.
(Murphy's Law)