Valcom v-9962 Service Manual

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V-9962

DIGITAL FEEDBACK ELIMINATOR

VSP V-9962

Issue 2

GENERAL

The V -9962 is a Digital Feedback Eliminator designed to
eliminate paging system acoustic feedback with an
option to prevent DTMF tones from being broadcast
through the paging system.

SPECIFICATIONS

Features

! Two audio outputs

Line level 600 ohm
Low impedance 8 ohm

(transformer isolated and separately adjustable)

! Audio input, 600 ohm, transformer isolated
! Three output relays - Play, Record, Busy
! LED Indicators
! Easy access volume controls
! Dip switch programmable
! Solid state, no moving parts
! Audio, DTMF, or contact closure activated
! DTMF message cancel
! Easy to install in new and existing systems

Access

! DTMF (Dual Tone Multi-Frequency)
! VOX (Voice Operated Switch)
! Contact Closure

Dimensions & Weight

Dimensions:
! 19.05cm H x 20.32cm W x 3.18cm D

(7.5"H x 8.0"W x 1.25"D)

! Weight: 1.36 Kg (3.0 lbs.)

Nominal Specifications

Input Impedance: 600 ohms
Input Level: -10 dBm
Line Level Output Impedance: 600 ohms

Output Level: -10 dBm (adjustable)

Speaker Level Output Impedance: 8 ohms

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Output Level: -10 dBm (adjustable)
VOX Sensitivity: -21 dBm (adjustable)
Release time after last sensed audio: 3 seconds

Nominal Power Requirements

! -24 VDC, 500 mA regulated "A" battery

Environment

Temperature: 0 to 40 Degrees C
Humidity: 0 to 85% non-precipitating

DESIGN

The V-9962 is designed to eliminate paging system
acoustic feedback with an option to prevent DTMF
tones from being broadcast through the paging system.
When a page is made, the message is digitized and
saved. Upon completion of the live page, the message
is released to play over the system speakers. This
eliminates the offensive squeal of feedback commonly
produced by telephones or microphones when making a
page.

947948

Valcom

Zone

Page Control

Unit

Output

FIGURE 1 - SIMPLIFIED BLOCK DIAGRAM OF A TYPICAL INSTALLATION

INSTALLATION

Cabling

A 25 pair cable with a female amphenol connector
should be run from the feedback eliminator to a 66B
type punchdown block. The cable should be terminated
on the block in standard color code order. (See Figure

2).

Mounting

NOTE: DO NOT install the V-9962 or its wiring
closer than 18" to a power supply or any equipment
that generates electrical noise.

___ 1. Using four #6 - 1/2" wood screws, mount the

feedback eliminator in a vacant space on the
backboard.

___ 2. Mount a 66B type punchdown block near the

unit and label the block per Figure 2.

___ 3. Connect the 25 pair cable to the punchdown

block per standard color code order.

___ 4. Connect the female amphenol connector to the

V -9962.

Connections

___ 1. Connect zone output from a 600 ohm page port

or Valcom page control to Audio In Tip
(W/BL) and Audio In Ring (BL/W) on the
punchdown block. (See Note at end of this
section).

___ 2. Connect page enable contact closure (if

available - this is an optional connection) to
COM (R/BL) and RECORD (BL/R) on the
punchdown block.

V-9962

Up to 150 Valcom
Amplified Speakers

___ 3. Connect Tip lead or terminal of amplified

speaker(s) to output 2; speaker level 8Ω
(W/BR) on the punchdown block.

___ 4. Connect Ring lead or terminal of amplified

speaker(s) to output 2; speaker level return
(BR/W) on the punchdown block.

___ 5. Connect -24Vdc from a filtered -24Vdc power

supply to pin 24 (BR/V) on the punchdown
block.

___ 6. Connect GND of the power supply to pin 49

(V/BR) on the punchdown block.
___ 7. Plug in power supply.
___ 8. The POWER ON LED on the V-9962 should

illuminate. (IF POWER ON LED does not light,

then using a voltmeter, measure voltage

between power terminals with negative probe

at pin #24 and positive at pin #49. If reading is

reversed, unplug power supply, verify V/BR

and BR/V pairs are properly connected at the

punchdown block and connector).

See Figure 3 for simplified block diagrams of typical
configurations.

NOTE: The input level must be attenuated using a V­1092 to prevent distortion if exceeding nominal input
levels for the V-9962; i.e., when used on a zone of
Valcom talkback page control (for one-way paging).

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