These are examples of the sounds generated by tone plant equipment by old Automatic Electric Step by Step switching systems.
GTE (Later Verizon, now mostly Frontier) phased out the last of their Automatic Electric step by step phone switch equipment in the late 1990s. These recordings were recorded in the summer of 1997, except where noted.
Dial Tone – Dial tone from Deland, Illinois – (217) 664 prefix.
Busy Signal – Busy signal from Phillipsburg, Ohio – (937) 884 prefix.
Reorder – Reorder (fast busy signal) from Long Point, Illinois – (815) 854 prefix.
Ringback Signal – Ringback signal from Honanunau, Hawaii – (808) 328 prefix.
1000 Hz Test Tone – An example of a 1000Hz test tone (sometimes called milliwatt tone) from Kingston, MI – (517) 683 prefix.
Busy Signal #2 – This is a busy signal from Bettsville, OH – (419) 986 (April 1998). It starts out as a ring, then goes into a “busy” signal. I assume it may be a test number.