That's one of the things I suggested when he posted the same question
in another newsgroup in the past week.
The first suggestion was that he buy a cheap phone, and use that
intact. It's obviously got the interface in place, and you get the
touch-tone encoder too.
Note also that in the other newsgroup, people are still wondering what
the purpose of this project is. Because a solution obviously comes
from the situation. If it's something like he has a rotary phone but
needs touch-tones to work with automated systems at the other end,
there's the time honored scheme of feeding the touch-tones into
a small amplifier and then speaker, and then holding the speaker
up to the microphone of the telephone. Solutions are a dime a dozen,
but none of them may apply until he reveals exactly what he's trying
to do.
Michael
Years ago, like late '80's, early '90's, I was doing a project at
Sperry.
They had some kind of digital phone system that wouldn't send DTMF,
plus they forbade long distance calls (but not 800 number calls)
without going thru the company operator with a project number to
charge to. Thus I couldn't call other clients.
I subscribed to (IIRC) Sprint, which had an 800 number you called,
then keyed in the number you wanted to call.
I found a device at Radio Shack that fit in a shirt pocket. You held
it up to the phone and dialed with the buttons on the device.
I don't know if it's still made or not. I still have mine around here
somewhere... I recall seeing it during an enforced office cleaning ;-)
I'll try to find it and get the RS part number.
Found it!
33 Memory Pocket Tone Dialer, Model 43-141, length of a pack of
cigarettes, but narrower and thinner, 3 AAA cells.
...Jim Thompson