Canon fax basic 2000 Manuale Di Servizio

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BASIC OF TELEPHONE

6.2.1 Details of signals and signs sent from the telephone 

to the exchange

(1) DC loop

This is for notifying the exchange that a person has picked up the handset.

A DC loop has the following meaning:

• Calling request and response (when DC loop is made)

• End of conversation (when DC loop is cut)

(2) Dialing signal

This signal is used to find the called party’s telephone. The signal is gener-

ated by dialing.

6.2.2 Details of signals and signs sent from the exchange 

to the telephone

(1) Dial Tone

This tone indicates that the exchange is ready and you may send the dial-

ing signals.

(2) Ring Back Tone

This tone indicates to the caller that the other party is being called up.

(3) Busy Tone

This tone indicates to the caller that the other party is busy.

(4) Calling Identification (CI)

This signal notifies the called party that there was a call from a caller.

This signal rings the bell on the called party’s telephone.

(5) Re-order Tone

This tone notifies the caller that the called party put down the handset dur-

ing a conversation and that the conversation was cut.

Some exchange do not output the Re-order Tone.

Of these signals that are sent to the telephone from the exchange, the sig-

nals (other than the CI) that the caller can hear through the handset are

called audio tones.