Here's video I took the other day of the monkeys line (248-228-3273) with a real TDD so it shows that the TDD stuff says EXACTLY what you would expect it to. 
Here's video I took the other day of the monkeys line (248-228-3273) with a real TDD so it shows that the TDD stuff says EXACTLY what you would expect it to.
Why does TDD sound like RTTY?
because they're both frequency shift keyed baudot?