Bogen MULTICOM 2000, Руководство по установке

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Analog Card Adjustment Procedure
The MCACB includes controls to adjust the Program/Page Volume, Compression, Talk Back Level, Switching
Sensitivity, and Switching Delay.
Adjustment instructions for the analog card.
1) Adjustment requires two people – one at a speaker station having the highest background noise level,
and one at a telephone at the circuit card location.
2) Do not use a speaker near the telephone that is being used, as this may make it difficult to adjust properly.
3) In wall-mounted systems, the controls can be reached through the slots in the side of the card frame. In
rack-mounted systems, adjustment requires the use of an extender card (Model MCEC).
4) The adjustment instructions listed here are for use by qualified service personnel only.
Caution: System Power must be OFF prior to removing or installing circuit cards.
5) Adjustment controls operate as follows:
Program Page Volume (R30): Clockwise rotation of this control increases program/page volume.
Compression (Listen) Level (R120): The compression level on the MCACB card is factory set
and not adjustable.
Speaker Volume (R53): Clockwise rotation of the control increases volume at the station loudspeaker.
Talk back Level (R75): Adjusts the talk back volume level in the handset earpiece. Clockwise rotation
increases the level; counterclockwise rotation decreases the level.
Switching Sensitivity (R119): Adjusts the point at which the VOX circuit will switch from talk back
to tally modes. Clockwise rotation increases sensitivity; counterclockwise rotation decreases sensitivity.
Switching Delay (R118): Adjusts the release time of the VOX circuit, allowing for short pauses
between words without causing the unit to switch to the talk back mode in the middle of a sentence.
Clockwise rotation increases the delay; counterclockwise rotation decreases delay.
Procedure
1) Set the switching sensitivity control (R119) at full counterclockwise position.
2) Set the switching delay control (R118) at about mid-rotation.
3) Have the person at the speaker location speak in a voice loud enough to overcome the ambient back-
ground noise level. Rotate the Talk Back Level control (R75) clockwise to obtain an acceptable volume
level over the handset (should be set on the low side to improve intelligibility).
4) With the person at the loudspeaker silent, rotate Switching Sensitivity control (R119) clockwise until the
switching becomes unstable (i.e., it switches back and forth by itself). Rotate the control counterclockwise
until the switching again becomes stable. At this point, the unit is critically stable; any noise on the telephone
side will cause the unit to switch to the talk mode and any loud impulse-type noise at the loudspeaker wall
cause the unit to switch to the talk back mode.