When connecting the ground of the arrestor to the chassis, tighten ARG on the PCB with a screw. At this time, the PCB is grounded through the power cable. The

TB1 arrestor ground terminal can also be used to connect to the earth directly.

4 DC circuits (R10, R11, C4)

These circuits provide DC characteristics according to the line requirements using the primary DC resistor in the line transformer T1 and the R10 and R11

resistors . The capacitor C4 bypasses AC signals.

5 Impedance matching network (R523, R536, C503)

This circuit matches the impedance between the line and equipment to reduce reflection of transmitted signals.

6 Receiving sensitivity (R574, R504)

The receiving sensitivity at line seizuring is determined by R574 and the MF tone receiving sensitivity at parallel pickup is determined by R504.

7 CML (RL1)

This circuit selectively switches the line between the telephone or facsimile.

8 SR (RL2)

This circuit connects the line with the telephone. During facsimile transmission, it disconnects the telephone.

A PP (RL6)

If this circuits detects MF or CNG tones without seizuring a line, it sets a proper receiving sensitivity.

B DP (RL3)

This circuit generates pulse dials. If the circuit detects MF or CNG tones without seizuring a line, it opens to increase the

impedance.

C Pickup RC (R5, C31)

These circuits insert a high-impedance resistor and capacitor serially to prevent the line impedance from dropping by the line transformer T1.

D Ring detectors (IC1)

These circuits detect a ring signal arriving to the line. If the input ring signal exceeds a specific voltage, the circuits output a signal having of RI the same

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