background image

 

 

 

 

 

Issue 2 

 

947933 

 

 
 

V-9933A 

NOISE SENSING VOLUME CONTROL 

 
 
GENERAL 

The V-9933A is designed to electronically adjust the 
level of a page by monitoring ambient noise levels in 
an area of a building. 
 

SPECIFICATIONS 

Purpose 

The V-9933A provides automatic paging level 
adjustments in areas where ambient noise levels are 
continuously changing. 
 

Application

 

• 

Valcom one-way paging systems  

 

Features 

• 

Solid-state design 

• 

Low power requirements 

• 

Self-contained or optional remote sensing device 

 

Capacity 

Each V-9933A will control the audio for up to 150 
Valcom one-way amplified speaker assemblies in a 
single zone.  Multiple V-9933A units can be used 
within the same zone. 
 

Additional Materials Required 

At the time of installation, the installer should provide 
the following materials: 

• 

24VDC power supply (If existing supply is 
inadequate) 

• 

Optional V-9934, Remote Sensing Device (Up to 4 
units) 

 

Dimensions/Weight 

The V-9933A is designed to be wall mounted.  

• 

7.30" H x 4.50" W x 2.00" D 

 

(18.54cm H x 11.43cm W x 5.08cm D) 

• 

0.9 lbs. (.41kg) 

 
Power Requirements

 

Power Requirement:         -24VDC Filtered Battery 
Operating Current: 

150mA  

 

Nominal Specifications

 

Automatic Level Adjustment Range: 

See Chart 1 

Power Output: 

-10dBm 

Frequency Response: 

50-12kHz +3dB 

Input Impedance: 

25k Ohms  

Output Impedance: 

8 Ohms  

Operating Temperature: 

0 to +50 degrees C 

Power Requirements: 

-24VDC signal battery 

Monitor Reset: 

5 seconds 

 

OPERATION 

The V-9933A, Noise Sensing Volume Control, 
continuously monitors the surrounding area noise by 
utilizing a built-in or optional remote microphone.  
When a page is made, the V-9933A electronically locks 
onto the last area noise sample.  A -23dBm signal or 
higher is required on the input before the 
V-9933A will activate and lock. 
 
Once activated, the amplifier is automatically set to the 
proper gain level for the amount of background noise.  
The amplifier will remain locked at that gain level for 
the duration of the page. 
 
After the page is made, there is a five (5) second delay 
before the V-9933A starts monitoring the area noise 
levels.  Refer to Figure 3 for a simplified schematic of 
the V-9933A. 
 
 

INSTALLATION 

These instructions cover only the installation 
procedure of the Valcom V-9933A.  Please consult 

Отзывы: