5
W/BL
BL/W
V-9941A
Connecting Block
T
R
Telephone System C.O. Line Position
or Loop Start Trunk Port
T R A A1
BR/W
BL/R
Inhibit
5.1K Ohm
CONNECTIONS FOR INHIBIT OPTION
Ground
Volume Adjustments
There are two volume controls on the V-9941A. The
control on the left adjusts the speaker to phone level
and the control on the right adjusts the phone to
speaker level. Turn the controls clockwise to
increase the volume.
__ a.
Speaker to Phone:
Adjust this control so the reply from the speaker is
clear. IMPORTANT: This is the most critical
adjustment. Set the volume at the lowest practical
level. Setting this control too high will increase
background noise without giving greater talkback
volume.
__ b. Phone to Speaker:
Adjust this control to give the desired listening level
at the speakers.
Optional Connections
A)
MUSIC:
__ 1.
Connect a pair from an amplified music
source to terminals 8 and 9 (MUSIC) of the
V-9941A.
__ 2.
Adjust the control on the music source for
the desired music level at the speakers.
B)
INHIBIT CONNECTIONS:
__ 1.
Verify the telephone being used has been
modified for "A" Lead Control. Contact the
telephone manufacturer for assistance if
required.
__ 2.
Connect Tip of the Telephone to terminal 1
of the V-9941A.
__ 3.
Connect Ring of the Telephone to terminal
2.
__ 4.
Connect the “A1” Lead of the Telephone to
the V-9941A terminal 3.
__ 5.
Connect the “A” Lead of the Telephone to
one end of a 5.1K Ohm 1/4 Watt resistor.
__ 6.
Connect the other end of the resistor to
V-9941A terminal 10.
OPERATION
The V-9941A provides a -24VDC battery feed on Tip
and Ring (SW3 ON). This provides "Talk Battery" to
allow proper operation of PABX loop start trunk
ports, Electronic Key system line key position or a
dedicated single line telephone. A loop sense circuit
connected with the battery feed turns on the V-9941A
on access from the phone system. Note: By turning
SW3 "OFF" and placing a ground on the ground start
terminal, the unit may be accessed.
Immediately after access the V-9941A will send a
tone to the speakers if the initial alert tone option has
been enabled (SW1-1). The user will then be able to
page to the speakers and receive a handsfree reply.
As long as the person originating the call remains
quiet, he will monitor the speaker. As soon as the
caller begins to speak, the VOX circuit will switch
and allow paging through the speaker. Throughout
the call, if the 15 second repeated alert tone has been
enabled (SW1-2) there will be a tone at the speaker
every 15 seconds. When the calling party
disconnects, the V-9941A will sense the open loop
from the phone system and automatically turn off the
speaker. If the V-9941A was accessed with a ground
on the ground start lead, the unit releases when the
ground is removed.
If the inhibit circuit has been connected to a single
line phone and that phone goes off hook during a
page, the V-9941A will sense approximately 5K
Ohms to ground through the “A” lead contacts of the
phone and it will turn off the speakers. Since the
telephone Tip and Ring has been connected to the
Valcom Tip and Ring, the called and calling parties
may now converse.
An internal relay will automatically connect a music
source (optional) to the speakers when the V-9941A
is idle and remove the music during a page. During a
page the music source will be connected to a 2.2 Ohm
load resistor.
