Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!inuxc!inuxh!rmrin
From: rmrin@inuxh.UUCP (D Rickert)
Newsgroups: sci.electronics
Subject: Re: Dial tone generation
Message-ID: <744@inuxh.UUCP>
Date: 30 Jan 89 17:16:56 GMT
References: <349@serene.UUCP>
Organization: AT&T Consumer Products, Indianapolis
Lines: 17

> 
>  
>      Well, according to my notes, a "precision dial tone" (whatever
> "precision" means)  is a combination of 350 Hz and 440 Hz (ie. those two
> frequencies at the same time).
>  
>  
>     Greg Bell_________________________________________________________
>       Hardware hacker          |
>       Electronics hobbyist     | UUCP:  uunet!serene!pnet12!gbell
>       EE major at UC San Diego |

In the bad old days, dial tone was produced by a motor generator set and
the frequency (and spectral content) of the tone was quite imprecise.
-- 

Dick Rickert  AT&T Consumer Products Laboratory