[comp.dcom.telecom] Dialtone Frequencies

gabe@sirius.ctr.columbia.edu (Gabe Wiener) (09/23/89)

Does anyone know when the common telephone dialtone (i.e. 350Hz and 440Hz
played together) was adopted?


Gabe Wiener - Columbia Univ.      "This 'telephone' has too many shortcomings
gabe@ctr.columbia.edu              to be seriously considered as a means of
gmw1@cunixd.cc.columbia.edu        communication. The device is inherently of
72355.1226@compuserve.com          no value to us."