Inovonics 235, Инструкция по эксплуатации и техническому обслуживанию

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EQUALIZATION settings through the five choices for each
end of the spectrum.
CLIP
PEAK
LIMIT
The final processing block of the 235 is a unique
asymmetrical “feedback” peak-limiter/clipper. A final
clipping circuit is able to monitor its own action and tell the
limiter how hard to work, depending on how aggressively
the PEAK PROCESSING (described next) has been set. This
feedback technique establishes a stable and fixed clipping
depth, or ratio between the two peak control functions. Two
LEDs flash as circuitry copes with program peak excursions,
enabling a visual interpretation of this limit-to-clip ratio.
PEAK
PROCESSING
Two up/down buttons select eight levels of program peak
control, indicated on the adjacent LED display. At the (MIN)
setting, typical values of peak reduction are on the order of
5dB, and no clipping is allowed. Setting number 2 also
restricts peak reduction to the same 5dB figure, but enables
a small amount of clipping as well. From setting number 3
upward, peak reduction runs about 10dB, with clipping
increasing as the setting approaches
(MAX)
.
NOTE: Always pay particular attention to the effect of
heavy peak processing on solo voices. Complex waveforms
such as instrumental music can tolerate a good deal more
clipping than solo vocals and voice announcements.
INPUT
GAIN
Input sensitivity of the Processor is adjusted by this 15-turn
potentiometer to accommodate varying input levels. The
control itself has 15dB continuous adjustment. This,
coupled with input level range jumpering (Figure 5, Page 9),
accommodates the 235’s full 30dB input signal level range.
The INPUT GAIN control is set so that normal program
material keeps the AGC indicator close to center-scale.
OUTPUT
LEVEL
This multi-turn control adjusts the Processor output level to
match the input requirements of the transmitter. The pot is
adjusted so that negative program peaks reach nearly 100%
modulation, as indicated by the station Modulation Monitor.
POS.
PEAKS
This adjusts Processor output asymmetry. It allows
naturally-occurring positive program peaks to exceed the
value of negative peaks. In the U.S., for example, the
maximum instantaneous value of carrier amplitude is
allowed to reach as much as two-and-one-half times the
unmodulated (resting) carrier value. This condition is
referred to as 125% positive modulation and references a
maximum figure of 100% negative carrier modulation, or
complete carrier cutoff.
POWER Harmonically in accord with today’s humanity-based
concepts of nurturing and self-esteem, Inovonics has
included this special switch, the operation of which
emPOWERs the operator of the Processor to reach new