Feeding audio signals into phone lines

[Bill@xxxxxxxxxxxxxxxxx (Bill Geluso)]

I don't know if this is the proper newsgroup in which to post this
question.  If it isn't, would you please advise me of a more
appropriate newsgroup.

Anyway, my question is:  What is the simplest (and least expensive)
way to feed an audio signal into a telephone line?

My specific application is as follows:  My speech is next to
impossible to understand due to cerebral palsy.  Therefore, I often
use a speech synthesizer to communicate with people, including
people over the phone.  Currently, to "speak" over the phone, I
depend on the microphone in a conference phone to pick-up the sound
waves coming from the speaker in my speech synthesizer.  While this
configuration works, the quality of the sound that gets transmitted
over the phone line is less than satisfactory.  This is why I am
seeking a direct way to input an audio signal into a phone line.

When making suggestions on how to accomplish what I want, please
keep in mind that I don't use a Windows computer with a sound card.
I still use a DOS computer, mostly because I can't/don't like using
a mouse.

I have a question about one possible solution to my problem:  My DOS
computer has an internal modem that has an on-board speaker, which I
can use to hear the audio output from the phone line very clearly.
Is there an internal modem that has some sort of input jacks?

I look forward to your answers and suggestions.

Bill Geluso


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