Inovonics 235, Инструкция по эксплуатации и техническому обслуживанию

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MODEL 235 TECHNICAL SPECIFICATIONS
Frequency Response (NRSC version) :
PROOF: ±0.25dB, 50Hz to 20kHz
OPERATE: ±0.5dB, 50Hz to 9.7kHz.
Follows NRSC pre-emphasis and
cutoff characteristics.
Distortion:
<1% THD at any PROGRAM
DENSITY
setting, and at
PEAK
PROCESSING settings which
maintain negligible clipping depth.
Noise:
Better than 60dB below 100% carrier
modulation (taken through NRSC de-
emphasis network).
Gated AGC:
UK/EBU quasi-peak “PPM” response
to program material; slow, 0.5dB-per-
second correction rate over ±10dB
range. Frequency-weighted gating
threshold set at –25dB, referred to
corrected input “zero” level.
Triband Compressor:
Second-order band-pass function;
crossovers at 250Hz and 2.5kHz.
Attack and release timing optimized
for each band.
PROGRAM DENSITY
controls timing and inter-band
“blending”.
Fixed Pre-Emphasis:
The standard (US) version follows the
“truncated” 75µs curve specified by
the NRSC transmission standard.
Alternative versions employ pre-
emphasis appropriate to the specified
cutoff frequency.
Variable Equalization
(see Figures 2
and 3 on Page 5) :
HF: –3dB, 0dB (NRSC), +3dB,
+6dB, +9dB; variable EQ
curves are in addition to the
NRSC or alternative fixed pre-
emphasis.
LF: –9dB, –6dB, –3dB, 0dB (flat),
+3dB.
Peak Controller:
Asymmetrical fast peak limiter
integral with hard peak clipper. PEAK
PROCESSING controls release timing
and program-dependent clipping
depth.
Low-Pass Function:
Phase-corrected, 9-pole FDNR active-
elliptic filter with proprietary
overshoot compensation. Exceeds
NRSC requirements. (See Figure 1
on Page 5.)
Input:
Active-balanced, bridging; accepts
nominal program line levels between
–15dBu and +15dBu.
Output:
Active-balanced, 200-ohm resistive
source; delivers 0dBm to +15dBm
into a 600-ohm load.
Output Asymmetry:
Positive peak amplitude may be
adjusted between 100% and 125% of
the negative peak value.
Remote Control Provision:
RS-232 serial data port (DB-9
connector) allows all processing
presets to be programmed or updated
by an IBM-compatible computer.
Necessary software is included.
Power Requirements:
105–130VAC or 210–255VAC,
50/60Hz; 15 watts.
Size and Weight:
1¾”H x 19”W x 10”D (1U);
10 lbs. (shipping).