CHAPTER 3 NDA-24296
Page 548
Revision 1.0
PA-4AMPC
AMP Pool Trunk

PA-4AMPC

AMP Pool Tr un k

1. General Function

This circuit card is bidirectional amplifier circuitry to be used for such a purpose as level guaranteeing in

a public line tie line connection. The ci rcuit card is provided with four bidirect ional amplifier cir cuits and

controls gains to speech loss which may vary with the kind of line involved in the connection. Also, this

circuit card is provided with the function to disable the AGC when modem signals such as FAX signals

have arrived.

Figure 3-168 Location of PA-4AMPC (4AMP) w ithin the System
AGC
Fix AMP
C.O. Trunk
ECa
PA-4AMPC
Tie Line N.W Tie Line Trunk
TSW
ECa:
ECb:
AGC:
FixAMP:
Echo Canceller which suppresses echo
in the hybrid circuit of a C.O. trunk.
Echo Canceller which suppresses echo
in t h e t ie - lin e si de.
Automatic G ain Con tro l circuit (ampl ifies
vo ic e si gn al s ar rivi ng fr o m th e publi c
network.)
vo ic e si gn al s ar rivi ng fr o m th e t ie -line
network.)
P ublic N .W
ECb
PAD
Fixed Gain Amplifier Circuit (amplifies
vo ic e si gn al s ar rivi ng fr o m th e publi c
network)
Fixed Gain Amplifier Circuit (amplifies
PAD: