[asterisk-dev] Can Asterisk detect A,B,C,D DTMF signals

[Andreas Sikkema]

On Jun 28, 2009, at 4:01 PM, Matt Florell wrote:
> As a side note, these DTMF signals have been around for decades, most
> telco infrastructure equipment supports these signals, and you can
> find very old linesman's handsets that have the A-D row of buttons on
> them.

I'm very careful with my ancient telephone which has a full DTMF  
keyboard exactly for this purpose. It's also a lot of fun to test on  
ATAs.

Unfortunately it's only allowed to be used on  
Fernsprechernebenstellenanlagen, so I can use it anywhere I like, I  
have no idea what those are ;-)

-- 
Andreas