AMERITECH AM8a, Инструкция по эксплуатации

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AM8a Instruction Manual (18-0037) Analysis Parameters
0037-S04.L_32 February 10, 2000
4-9
4.11.2
OFF HKvdc(min):
This parameter sets the threshold the AM8a uses to determine
OFF
HOOK
status when it is configured to
ANALOG
(loop). The dc voltage present across
the Tip and Ring leads must fall below this threshold (towards zero, regardless of
polarity) before the AM8a will recognize an
OFF HOOK
condition. This threshold will
also affect the ability of the AM8a to detect dial
PULSE
digits. The next sub-section
provides the procedure to determine the best setting of this parameter.
4.11.3
Procedure to Set OFF HKvdc(min) Threshold:
The on/off hook threshold TO voltage
must be carefully set to ensure the AM8a correctly recognizes
ON
and
OFF
hook
events. The setting may have an effect on the operation of the
PULSE
digit analyzer,
since
PULSE
dialing is accomplished by opening and closing of the loop. (
ON/OFF-
HOOK
).
A quick way to determine the setting of what voltage to set the threshold voltage is to
use the
METER DISPLAY
as follows (refer to sub-section 6.4):
1. When the
LINE/TERM
equipment is
ON HOOK
, measure the Vt–r dc. This voltage
should be equivalent to the battery supply of the switching equipment.
2. Go
OFF HOOK
with the
LINE/TERM
equipment and again measure the Vt–r dc.
This voltage will indicate the
OFF HOOK
voltage and should be the minimum
voltage encountered under normal operation.
3. Now set the
OFF HK
vdc(min) parameter for a voltage between the two measured
voltages.