P
AGE
4
44124-0798 <90-00024>
F
IG
. 2 - F
UNCTIONAL
S
CHEMATIC
, 44124
13
7
41
47
9
43
1dB
2dB
4dB
8dB
1dB
2dB
4dB
8dB
1dB
2dB
4dB
8dB
1dB
2dB
4dB
8dB
49
55
15
5
MON
IN
IMPED
ANCE
MA
TCHING
TRANSFORMER
2713 Hz LOOPBA
CK
DETECT
OR & CONTR
OL
CIRCUIT
SEALING
CURRENT
SUPPL
Y
S6
AMBER
LED
SC
SXT
SC
S4
K2
LGL
G
S2
K2
-48 VDC
S5
SXR
V
NOR
SIDE B
LINE SIDE
C
SXT
SC
S4
SX
SX1
RCV
INPUT
R
T
35
17
-21 TO - 56 VDC
-BA
TT
GR
OUND
REGULA
TED
PO
WER
SUPPL
Y
T1
150
Ω
1200
Ω
600
Ω
PWR
GREEN LED
INPUT EQ
U
ALIZER CIRCUIT
(A
CCUMULA
TIVE SETTINGS)
2713 Hz LOOPBA
CK
DETECT
OR & CONTR
OL
(A
CCUMULA
TIVE SETTINGS)
INPUT AMPLIFIER CIRCUIT
(A
CCUMULA
TIVE SETTINGS)
OUTPUT AMPLIFIER
(A
CCUMULA
TIVE SETTINGS)
K1
LOOPBA
CK
RELA
YS
S8 SLOPE
S7 BAND
WIDTH
S7 AMPLIFIER (HT)
S12 LOOPBA
CK LEVEL
S1
1 dB GAIN LOSS
S13
GAIN LOSS
NL
K1
T2
S1
2W
4W
.1dB
.2dB
.4dB
.8dB
1.5dB
3
d
B
6
d
B
12dB
S1 LEVEL SETTINGS
S3
GAIN LOSS
IMPED
ANCE
MA
TCHING
TRANSFORMER
T2
K1
S12-3
-20 VDC
RED LED
20
Ω
LB
MLB
GR
OUND
MLB (MANUAL LOOPBACK)
TEK 6
LOOPBA
CK
19
1
23
TEK 5
21
RI/DRI
RCV
OUTPUT
TI/DTI
R/DR
XMT
INPUT
T/DT
3
51
B/T2 SIMPLEX
A/T2 SIMPLEX
EQR
BYP
S9
SIDE A
DROP SIDE
MON
OUT
XMT
OUTPUT
T1
R1
T3
150
Ω
1200
Ω
600
Ω
A to B
A to B
B to A
B to A
SXR
V
NOR
NOR
S5
K1
NL
.1dB
.2dB
.4dB
.8dB
1.5dB
3
d
B
6
d
B
12dB
B to A
OUT
A to B
IN/2W
NOR
CIRCUIT DESCRIPTION