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INSTALLATION
Analog Input
Fine Level
Adjustments
TABLE 2-10. OPTION SELECTIONS, INPUT LEVEL ADJUSTMENT
S1-2
S1-3
(–2 dB)
(+1 dB)
OFF
ON
OFF
ON
OFF
OFF
OFF
OFF
ON
ON
ON
ON
ON
OFF
ON
OFF
OFF
ON
OFF
ON
OFF
OFF
OFF
OFF
ON
ON
ON
ON
ON
OFF
ON
OFF
2-10
The analog sections in both transmit and receive directions have ad-
justments to fine tune the signal amplitude to compensate for installa-
tions where the input levels are not within the –16 to + 0 dB range or when
excessive output cable lengths require greater than nominal signal drive.
The amplitude of the input transmit signal to the transmit circuit can be
adjusted in 0.5 dB steps in the range –6.0 to +1.5 dB (approximately a 0 to
–16 dBm transmit level selection) by DIP switches S1-2, S1-3, S1-4 and S1-
5. Refer to Table 2-10 for setting of the DIP switches.
Similarly, the amplitude of the output receive signal from the receive cir-
cuit can be adjusted in 0.5 dB steps in the range –6.0 to +1.5 dB
(approximately a 0 to + 7 dBm receive level selection) by software via the
TMS/supervisory controller.
For instructions on how to align the levels, refer to Appendix D, CELP
Circuit Voice Level Testing.
S1-4
S1-5
(–4 dB)
(+0.5 dB)
OFF
ON
OFF
OFF
OFF
ON
OFF
OFF
OFF
ON
OFF
OFF
OFF
ON
OFF
OFF
ON
ON
ON
OFF
ON
ON
ON
OFF
ON
ON
ON
OFF
ON
ON
ON
OFF
Input
Compensation
+1.5 dB
Switches S1-2 through S1-5 select attenuation
or amplification for the voice input level. This
+1.0 dB
compensates for cable losses or improper
+0.5 dB
output
0.0 dB
equipment. The switch selects a level of
–0.5 dB
compensation from +1.5 dB to –6.0 dB, in 0.5
–1.0 dB
dB steps. Each segment of switch S2 selects a
level of attenuation or amplification;
–1.5 dB
individual steps are added to produce a
–2.0 dB
particular
–2.5 dB
compensate for some measured deviation of
–3.0 dB
the output level of equipment connected to the
–3.5 dB
channel. The deviation is the
between the actual level and the nominal level
–4.0 dB
of 0 dBm or –16 dBm selected on switch S1-1.
–4.5 dB
For example, if the nominal level is 0 dBm, and
–5.0 dB
the actual level is +2 dBm, selection of –2 dB
–5.5 dB
would compensate for the difference between
–6.0 dB
the nominal and measured input values.
Application
levels
from
connected
level.
A
level
is
telephone
the
selected
to
difference
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