ConTronic AVM 1 Bedienungsanleitung Seite 11

(19) Gain indicator
This LED chain indicates the current AVM•1 amplification
level. The amplification is at its maximum level when all
the LEDs are on.
If all of the LEDs are off, the amplification is at its mini-
mum level.
The range between min and max corresponds to the maxi-
mum possible control range on the AVM•1 and depends
on the positions of the ratio and range controllers.
If, for example, the ratio controller is on 0 and the range
controller is on 1dB, the difference between min and max
is very small, i.e. there is almost no change in amplificati-
on. This range is, however, still shown on the LED chain.
(20) Increase / reduce LED
This LED lights up red when the amplification increases. It
turns green when the amplification is reduced. In balan-
ced position, the LED flashes red and green alternately.
When the amplifier is at the lowest range limit, i.e. when
amplification is reduced as far as possible, the LED
remains green. When the amplification is at maximum
level, the LED remains red.
If the AVM•1 is muted or the protection switch is active,
the LED switches off.
(21) AWU active LED
This LED lights up red when the AWU protection switch is
active.
(22) AWU controller
AWU protection switch: (Anti Wind-Up protection switch)
If loud music or speech is being transmitted, the measu-
ring microphone may interpret this signal as ambient noise
and continue to increase the amplification, even though
the surrounding noise level has not increased.
To avoid system build-up of this kind, the AVM•1 conti-
nuously measures the level of the signal. If this level is too
high, the volume control is switched off and the amplifica-
tion is kept constant until the level of the signal is redu-
ced. In this case, the AVM•1 therefore only measures the
surrounding noise level when there is a pause in the
speech or music.
The AWU controller is used to set the level of the signal,
i.e. where the AVM•1 is to ignore the microphone signal
and not adjust the amplification.
(23) Max / min gain switch
The volume control range limits can be switched on using
this switch. This enables you to check how loud the volu-
me is when the amplification is set to minimum and maxi-
mum.
The switch serves as an adjustment aid, allowing the range
limits to be adjusted easily.
When the unit is in operation, the switch is in the central
position run.
(24) Time fast/hold switch
This switch can be used to temporarily switch the control
time constant to fast. When the switch is in the hold positi-
on the current amplification is retained. When the unit is in
operation, the switch is in the central position run.
The switch serves as an adjustment aid.
With Fast , the control reaches a steady state very quickly,
which may therefore prevent long waiting times, as is the
case with large time constants.
Using hold allows e.g. equalizer settings to be optimized
more easily because the volume does not change.
(25) Time controller
The time constants of the volume control are adjusted
using this knob. For an adjustment of 20 dB, the range
extends from 1 to 250 seconds.
In the case of background music, a long time constant is
usually selected so that the volume of the music does not
change if a telephone rings or if there is a similar burst of
loud noise.
At information terminals, where ambient noise (e.g. traffic
noise) fluctuates rapidly, a short time constant is recom-
mended.
To avoid making adjustments when configuring a time con-
stant that has been found, a short temporary time constant
can be set using the time fast switch.
(26) Ratio controller
The ratio controller is used to set the level of amplification
readjustment. When turned fully to the right, the volume is
adjusted at a ratio of 1:1.
If the ambient noise level doubles, the volume of the signal
also doubles.
When turned fully to the left (0), the volume of the signal
does not increase, even if the surrounding noise level chan-
ges.
The change is therefore made in the ratio ratio / 1, where
ratio lies between zero and one.
(27) Min. controller
The surrounding noise level where the AVM•1 begins
readjustment is set using this rotary knob. It begins to
increase the volume of the signal.
This level can be set to between 50 and 70 dB.
50 dB correspond to e.g. a quiet room where a conversati-
on is taking place.
70 dB is attained e.g. on a street with average traffic volu-
mes.
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