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Central Control Tones

The 1960 Morris ESS Trial: Tone Plan

The quoted text below, is, save for mild reformatting and insertion of inline links to audio, the same as in the book.

Dial Tone

(Play sample)

The dial tone (a steady tone) is a combination of two frequencies, 560 cycles and 690 cycles. It is supplied to fifteen tone points in the distribution switching network.

Busy Tone

(Play sample)

The busy tone is a combination of two frequencies, 560 cycles and 690 cycles, interrupted at a rate of 60 ipm (0.5 second on, 0.5 second off). It is supplied to fifteen tone points in the distribution switching network.

Reorder Tone

(Play sample)

The reorder tone is a combination of the same two freqencies, 560 cycles and 690 cycles, interrupted at a rate of 120 ipm (0.3 second on, 0.2 second off). It is supplied to fifteen tone points in the distribution switching network.

Audible Ringing Tone

(Play sample)

The audible ringing tone is a combination of two frequencies, 430 cycles and 454 cycles, interrupted at a rate of 15 ipm (2 seconds on, 2 seconds off). It is supplied to five tone points in the signal switching network.

Ringing tones

Party NumberFrequencySample
1532WAV file
2591WAV file
3656WAV file
4729WAV file
5810WAV file
6900WAV file
71000WAV file
8478WAV file

The ESS serves eight-party lines on a selective ringing basis. Therefore it needs eight different frequencies of ringing tones. Each ringing tone is a single-frequency tone pulsed at 12.5 pps and intrreputed at a rate of 15 ipm (2 seconds on, 2 seconds off). The eight tones are supplied to forty tone points in the signal switching network.

Revertive Ringing Tones

Since the ESS serves two-party and eight-party lines, it needs ringing tones for reverting calls. These tones are single-frequency tones pulsed at 12.5 pps and interrupted at a rate of 62.5 ipm (0.48 second on and 0.48 second off). The revertive ringing tones are supplied to eight tone points in the signal switching network.

On the first ringing cycle, 0.96 second, the called party ringing tone is connected to the line. On the second cycle, the called party ringing tone is disconnected and the calling party ringing tone is connected. This alternating of the ringing tones for the called party and the calling party is continued until the called party answers, or until the connection times out and releases.

Asterisk

So, the natural question after reading all of this is: How can I use these tones on my Asterisk system? Well, it's actually very easy. Just add these lines somewhere in your /etc/asterisk/indications.conf file:

[us-m]
description = United States (1960 Morris, IL ESS Trial)
ringcadence = 2000,2000
dial = 560+690
busy = 560+690/500,0/500
ring = 430+454/2000,0/2000
congestion = 560+690/300,0/200
callwaiting = 591/300,0/10000
dialrecall = !560+690/100,!0/100,!560+690/100,!0/100,!560+690/100,!0/100,560+690
record = 1400/500,0/15000
info = !591,1000
stutter = !560+690/100,!0/100,!560+690/100,!0/100,!560+690/100,!0/100,!560+690/100,!0/100,!560+690/100,!0/100,!560+690/100,!0/100,560+690

Then, near the top of the file, change the country variable to read:

[general]
country=us-m

Do note that the zone name can only be four characters long, it seems.