11
Any input will provide audio at both the 8 Ohm
and 600 Ohm outputs. Signals coming from the
8 Ohm output will be maintained 7dB below the
level of the paging (this is not user adjustable).
There is no modification of page or music
signals when using the 600 Ohm output. The
600 Ohm output also provides a loop on access
and may be used with loop start paging
equipment.
In the idle state, signals from the music input will
appear on both the 8 Ohm and 600 Ohm
outputs. On receipt of superimposed ring
generator on Tip and Ring, the V-9940 will be
activated and will place a loop across the station
Tip and Ring for ring trip. An answer verification
tone will then be returned to the calling party and
Tip and Ring audio will be connected to the 8
Ohm and 600 Ohm outputs.
After access, the reset circuitry is turned on. If
the unit is set for loop detect, it will ignore any
open loop conditions for the first second, then it
will release when it senses an open loop on Tip
and Ring lasting at least 150ms. If you are
using the audio sense reset, the unit will stay on
line until sensing a lack of audio (-22dB or less)
for the period set by the dip switches. If using
the time out reset, the unit will stay on the line
for the preset length of time and then will reset,
whether the page is complete or not. Upon
release, the music source is reconnected to the
outputs.
All call, if connected, will override both the music
and page inputs. All call requires an additional
station port for access and must be wired as
shown in Figure 6. When the all call station
number is dialed, any paging in progress will be
overridden and an alert tone will be returned to
the overridden parties. If they remain on line, on
completion of the all call page, they will be
reconnected to their respective zones and all
timers will be reset, allowing a full page again on
each zone.
TECHNICAL ASSISTANCE
When trouble is reported, verify that power is
being supplied to the unit and there are no
broken connections. Check voltages for proper
polarity on the crossconnect block. Table 1
identifies symptoms of possible problems with
solutions. If a spare unit is available, continue to
troubleshoot by substituting the spare unit for
the suspected defective unit.
Assistance in troubleshooting is available from
the factory. When calling, you should have a
VOM, several clip leads, a telephone test set
available and call from the job site. Call (540)
563-2000 or visit our website at
http://www.valcom.com.
The V-9940 is not field repairable. Valcom, Inc.
maintains service facilities in Roanoke, VA.
Should repairs be necessary, attach the
company name, address, phone number,
contact person and the nature of the problem.
Send the unit to:
Valcom, Inc.
Repair and Return Dept.
5614 Hollins Road
Roanoke, VA 24019-5056
VALCOM LIMITED WARRANTY
Valcom, Inc. warrants its products to be free from defects in materials and workmanship under conditions of normal use and service
for a period of one year from the date of shipment. The obligation under this warranty shall be limited to the replacement, repair or
CONTROL,
OPTION &
TIMING
CIRCUITS
AUDIO
SENSE
XFORMER
TONE
GEN.
ALL CALL IN
ALL CALL OUT
MANUAL RESET
RING
DETECT
LOOP
XFORMER
T
R
ACCESS
XFORMER
MUSIC IN
ALL CALL
AUDIO IN
XFORMER
PREAMP
AGC
8 OHM
OUT
600 OHM OUT
K2
K3
POWER
SUPPLY
-
24VDC
GROUND
-12
-24
MAKE
STATIONARY
BREAK
SIMPLIFIED SCHEMATIC
