Operation; Technical Assistance; Circuit Description - Valcom V-1109RTVA User Manual

set. THE MUSIC INPUT LEVEL FROM THE
MUSIC SOURCE SHOULD BE LIMITED TO
0.25VRMS MAXIMUM. A SOURCE LEVEL
GREATER THAN 0.25VRMS WILL RESULT IN
PERMANENT DAMAGE TO THE
BACKGROUND MUSIC AMPLIFIERS
CONTAINED IN THE V-1109RTVA. The music
source should be connected to the V/G Pair on
the connecting block for the Page Control Unit.

OPERATION

This unit provides multi-zone page access
provisions to appropriately interface with the
telephone system being used. A preamplifier
conditions the audio from the telephone system
tip and ring and provides a low impedance low
level output to the desired page zone.

Circuit Description

When a station user lifts his handset to make a
page, the switchhook contacts in the telephone
close the tip and ring to form a loop which returns
battery back to turn on transistor Q1. Transistor
Q1 operates relay and logic circuits to return dial
tone and lamp battery to the telephone set. Logic
circuits receive dialing information and operate
relays and/or circuitry to provide a ringback tone
and a one-way connection for the zone selected.

TECHNICAL ASSISTANCE

When trouble is reported, verify that power is
being supplied to the unit and there are no broken
connections. Be sure that the amphenol is
secure in the back of the unit. Check voltages for
proper polarity on the crossconnect block.
A lineman's test set, several clip leads and a
VOM may be necessary to effectively
troubleshoot the unit.
Table 3 identifies some possible problems and
solutions.
If a spare unit is available, continue to
troubleshoot by substituting the spare unit for the
suspected unit.
Assistance in troubleshooting is available from
the factory. When calling, you should have a
VOM and a telephone test set available and be
calling from the job site. Call (540) 563-2000 for
Technical Support or visit our website at
http://www.valcom.com.
Valcom equipment is not field repairable. Valcom
maintains service facilities in Roanoke, VA.
Should repairs be necessary, attach a tag to the
unit clearly stating your 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
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