Canon fax basic 2000 서비스 매뉴얼

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FACSIMILE SYSTEM

3.5

Dial Control

The dial control function generates dial pulses (DP). Application of ON/

OFF switching of 

 is often adopted as a method of generating dial

pulses. The following shows the basic configuration of the dial control cir-

cuit.

Fig. 6-10   Dial Control Circuit

To generate the dial pulse, the DC loop is formed by the P relay. The dial

pulse is generated by turning this relay ON and OFF. If the S relay remains

ON while the dial pulse is being generated, the pulse waveform is influ-

enced by the DC seize circuit that is located after the S relay, and changes

as follows.

Fig. 6-11   Waveform of Weak Pulse

The waveform changes as follows when the S relay is turned OFF to indi-

cate that it has been shaped.

Fig. 6-12   Waveform of Clear Pulse

DC cut
capacitor

S relay

P relay

DC seize

circuit

L1

L2

+

ON

OFF

Influence of DC seize circuit