Valcom v-9927a Service Manual

V-9927A

DIGITAL MULTI-TONE GENERATOR

INTRODUCTION

The V-9927A was designed with ease of installation
and flexibility in mind. Connections are by screw
terminals located on the edge of the PCB. The
various options and tones are set using option blocks
located inside the enclosure on the PC Board.

The V-9927A is a microprocessor controlled multi­tone generator capable of producing a variety of tone
signals for various applications. It is functional and
backward compatible with the previous V-9927.

Note: Double check all wiring as connections to
the unit are different.

This equipment has been tested and found to
comply with the limits for a Class A digital device
pursuant to Part 15 of FCC Rules. These limits are
designed to provide reasonable protection against
harmful interference when this equipment is operated
in a commercial environment. This equipment
generates, uses and can radiate radio frequency
energy and if not installed and used in accordance
with the instruction manual, may cause harmful
interference to radio communications. Operation of
this equipment in a residential area is likely to cause
harmful interference in which case the user will be
required to correct the interference at his/her own
expense.

VSP-9927A

Issue 4

INSTALLATION

Product is intended for wall mounting only. When
mounting, open enclosure and remove circuit board.
Screw back of enclosure to backboard near the
telephone system common equipment. Snap circuit
board back in place. Both mounting holes must

be utilized to insure secure mounting of the unit.

Make connections and set tones, using option
blocks, as required for the specific application.
Refer to Tone Table on page 2 for tone descriptions.

Replace cover and plug in power supply.

OPERATION

All Tones (Except Code Call)

Operation of the V-9927A is accomplished by
applying a connection between the COM (Common)
terminal on the terminal block and the desired tone
number (1-8).

SPECIFICATIONS

Power Requirements:

-24VDC “B” Battery at 100mA

Operating Environment:

Temperature: 0 to +50° C
Humidity: 0 to 85% (non-condensing)

Nominal Input/Output Specifications:

Input Impedance: 600 Ohms
Output Impedance: Less than 4 Ohms
Min. Output Load Impedance: 20 Ohms
Audio Input: 0dBm nominal
Maximum Tone Output: > 0dBm single tone

Physical Dimensions:

8.20”H X 4.55”W X 2.30”D
(20.83cm H x 11.56cm W x 5.84cm D)
Weight: 1.5 lbs (0.68 kg)

The Tone selected by terminal number 1 has priority
over others. If multiple tone inputs are being used, it
is possible to sequence tones by closing the appro­priate contacts in the desired sequence. However,
Tone number 1 will always be placed first on the list
when it has been activated.

If multiple tones are selected at the same time, the
LOWEST tone number will have priority. If the
lowest contact is open, then the next lowest tone
number will be activated.

When a Tone is activated the INPUT source will be
faded out in 0.75 seconds if P5 is out or will be faded
out in 0.25 seconds if P5 is IN.

The V-9927A has a buffer for 32 tones. If more than
32 tones are entered within a short period, the
V-9927A will drop the last tone entered.

Figure 2 illustrates several of the ways the V-9927A
can be used with other Valcom equipment.

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Code Call Operation

When the V-9927A is connected to the V-9923A code
call unit, the V-9927A will respond to the contact
closure inputs and issue single chimes in response
(see Figure 2).

At the beginning of a Code Call sequence, the
INPUT source will be faded down about 6dB. It will
remain at this level until the CODE CALL sequence
has completed (including the interdigit time). At that

TONE TABLE

CONNECTION

ON

JP1 P3

COM - TONE 1
COM - TONE 2
COM - TONE 3
COM - TONE 4
COM - TONE 5
COM - TONE 6
COM - TONE 7
COM - TONE 8
COM - TONE 1
COM - TONE 2
COM - TONE 3
COM - TONE 4
COM - TONE 5
COM - TONE 6
COM - TONE 7
COM - TONE 8

OPTION

BLOCK DESCRIPTION

IN
IN
IN
IN
IN
IN
IN

IN
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT

* WHOOP, 698Hz, 3.9 seconds (approx.) 2 cycle minimum
* DUAL CHIME, 880Hz/698Hz
* BURST, 880Hz, 1/2 second on, 2 seconds minimum
* STEADY, 880Hz, 3 seconds minimum
TeleBell 986/784Hz, 11 per second, 10 minimum
Chimes, 986, 784, 659, 523Hz order
Chimes, 880, 698, 587, 494Hz order
CODE CALL CHIME, 784Hz (V-9923A standard)
> SIREN, 659Hz, center 1 cycle (approx.) 0.3Hz
> WHOOP (yelp) 659Hz, 2.5Hz, 4 minimum
> WARBLE, 494/986Hz, 6Hz rate
> STEADY 698Hz, 1 second minimum
> BURST (pulse), 494Hz, 4.5Hz rate
Chimes 659/784Hz
Chimes 986/784Hz
CODE CALL CHIME, 784Hz (V-9923A Standard)

time, the INPUT source will be faded back up to
normal level.

When using the CODE CALL option with other tone
options, the CODE CALL may be interrupted to place
other tones in the sequence (including Tone number
1 with higher priority). However, the CODE CALL
may be out of sequence for the period that this
occurs.

NOTE: * denotes V-9927 compatible tones

> denotes “USA Standard Immediate Evacuation signal for industrial areas”

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