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Overview
Second Audio Program Generator
A BTSC-standard SAP subcarrier generator, the 8182ASAP includes one channel of OPTIMOD-TV audio processing. It can be used alone, with the Orban TV Stereo Generator 8185A or with the earlier 8182A/SG.
Features
- Functions independently or with Orban TV Stereo Generators.
- Incorporates full-quality OPTIMOD-TV audio processing.
- Subcarrier generator has extremely low distortion and excellent transient response to cleanly achieve maximum average.
- subcarrier modulation.
- Includes genuine dbx NR encoder.
Specifications
PERFORMANCE
Frequency response (PROOF mode, N/R in): ±0.75dB, 50-10,000Hz. Measured with reference SAP demodulator and professional N/R decoder.
Noise: -75dB referenced to 100% modulation, 50-10,000Hz; -81dB typical.
Total system distortion-N/R in (PROOF mode, 100% modulation): <0.4% THD, 50-10,000Hz. <0.4% SMPTE Intermodulation Distortion. Measured with reference SAP demodulator and professional N/R decoder.
Total system distortion-N/R out (PROOF Mode, 100% modulation):<0.2% THD, 50-10,000Hz. Measured with 75us preemphasis and deemphasis.
INSTALLATION
LOCATION
Up to 100ft (31m) RG-58A/U from exciter or 8182A/SG.
AUDIO INPUT
IMPEDANCE: 10k ohm load impedance, electronically balanced by means of true instrumentation amplifier. Requires balanced source or £600 ohms. Common mode rejection >60dB @ 60Hz.
Sensitivity:-30dB to +10dBm to produce 10dB "Master Band" gain reduction @ 1kHz.
Connector: Barrier strip (#5 screw), EMI suppressed.
SYNC REFERENCE INPUT
Impedance: 20k ohms, balanced. Switchable 75 ohm termination.
Level: Composite video or sync, 0.6 to 1.6V p-p; 1V nominal.
Connector: Two BNC connectors, looped-thru, shell insulated from chassis.
SAP OUTPUT
Impedance: Voltage source (0 ohms) or 75 ohm source impedance (selectable with internal jumpers), single ended, impedance independent of OUTPUT LEVEL setting.
Level: Adjustable from 0 to>2.2V peak (4.4V p-p) with 18-turn OUTPUT LEVEL control.
Load: When jumpered for voltage source, will drive two 75 ohm loads in parallel. Maximum permissible load capacitance 0.047uF.
Connector: BNC, floating over chassis ground to permit interface to other equipment without need for wideband transformer to suppress ground loops. EMI suppressed.
MONITOR OUTPUT
Configuration: N/R decoded (or 75us deemphasized, depending on setting of internal MONITOR N/R In/OUT switch).
Impedance: 600 ohm source impedance, single ended.
Level: Fixed; 5V peak corresponds to 100% modulation.
Connector: Barrier strip (#5 screw), EMI suppressed.
REMOTE CONTROL
Function: Selects SAP ON/OFF, Loudness controller ON/OFF.
Voltage: 6 to 24V AC or DC, momentary or continuous, optically isolated. 22VDC supplied to facilitate use with contact closure.
Connector: Barrier strip (#5 screw).
SYNC LOCK INDICATOR
Configuration: Relay-controlled contact closure to indicate successful lock to sync or composite video. Limit applied voltage to 50v, total load to 10VA non-reactive, current to 0.5A.
Connection: Barrier strip (#5 screw).
POWER
115/230VAC (switch selectable), ±15%, 50-60Hz; 31VA. IEC mains connector with detachable 3-wire "U-ground" power cord supplied. Leakage to chassis <0.5mA. AC is EMI suppressed.
Ground: Circuit ground is independent of chassis ground; both appear on terminal strip on rear panel for strapping as required.
DIMENSIONS
19" (48.3cm) W, 7" (178cm) H, 12.5" (31.2cm) D. 4 rack units.
ENVIRONMENTAL
Operating temperature range 0-50 degrees C (32-122 degrees F). Humidity 0-95% RH, non-condensing.
CIRCUITRY
INPUT CONDITIONING, CROSSOVER, "MASTERBAND" COMPRESSOR, "BASS BAND" COMPRESSOR. HIGH-FREQUENCY LIMITER Same as 8182A OPTIMOD-TV.
DISTORTION-CANCELLED CLIPPER (US Patent No. 4,208,548)
Operation: Provides peak limiting function.
Nominal bandwidth: 10kHz.
Distortion cancellation: Clipping distortion below overshoot compensator threshold cancelled better than 30dB, 0 to 2,200Hz; 40dB typical.
FREQUENCY-CONTOURED SIDE-CHAIN (FCS) OVERSHOOT COMPENSATOR (US Patent No. 4,460,871)
Same as 8182A OPTIMOD-TV.
LOWPASS FILTER
Type: 10kHz ninth-order elliptical filter. Follows N/R encoder.
Passband response: Typically +0.05, -0.1dB to 10,000Hz.
Stopband rejection: Affords > 80dB protection to stereo subchannel.
SAP GENERATOR
Residual FM noise: -70dB referenced to 100% modulaton (with 75us deemphasis).
Specifications subject to change without notice.