Orban 8182A, Operating Manual

Page 1: ...Operating Manual OPTIMOD TV Audio Processor Model 8182A...

Page 2: ...ASAP E 8182A SAP OPT 021 BTSC SAP Generator w Monitor Card 230V 8182APRO 8 182A PRO BTSC PRO Generator for 8182A SG 8185APRO 8 185A PRO BTSC PRO Generator for 8185A Supplied with 3 and 4 TX cards and...

Page 3: ...illed into the enclosure through openings Damage Requiring Service The appliance should be serviced by qualified service personnel when The power supply cord or the plug has been damaged or Objects ha...

Page 4: ...de service apresvente autorise Safety Instructions Spanish Hacer funcionar el aparato solo con la tension y clase de corriente senaladas en la placa indicadora de caracterlsticas Reemplazar los fusibl...

Page 5: ...king When you pack the unit for shipping Tighten all screws on any barrier strip s so the screws do not fall out from vibration Wrap the unit in its original plastic bag to avoid abrading the paint Se...

Page 6: ...s into the 8185A mainframe Separate manuals are provided with all of these products Note in particular that integrated setup instructions for OPTIMOD TV Model 8182A and the Orban 8185A are provided in...

Page 7: ...ters to LED bar graph meters To do this upgrade we have replaced the meter resistor card documented in the manual Otherwise all information provided in the 8182A manual is valid for your 8182A unit Th...

Page 8: ...eld TOTAL component of the master gain reduction We will describe Meter 1 the TOTAL meter Current source Q 1 R7 R5 R6 CR5 applies a constant current to the series con nected diodes in LED assembly CR1...

Page 9: ...of IC6 A which acts as a comparator Positive feedback from the output of IC6 B through R2 causes the output of IC6 A to abruptly change state each time the output of IC6 B reaches approximately 0 046V...

Page 10: ...C1 5 Quad Comparator 24710 302 NAT LM339 IC6 Linear Dual Opamp 24206 202 Tl TL072CP MOT IC7 11 Quad Comparator 24710 302 NAT LM339 IC12 Linear Single Opamp 24013 202 Tl TL071CP Miscellaneous J1 Cable...

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Page 12: ...xk D B D R5 1 QQK IX CRS IN 41 48 R6 75K 1 X c B Vx orbon TITLE SCHEMATIC 81 82A LED METER DISPLAY 61 141 000 01 Sheet 2 of 2 i...

Page 13: ...SOLDER SIDE WHERE INDICATED USE TEFLON TUBING ON ALL LED LEADS MARK REVISION LEVEL IN SPACE PROVIDED gZZ3 S2 ul j SQUARE PADS INDICATE PIN 1 OF CONNECTORS CATHODE OF DIODES POS SIDE OF CAPS PIN 1 OF I...

Page 14: ...Operating Manual OPTIMOD TV Audio Processor Model 8182A...

Page 15: ...2 001 495 Other patents pending OPTIMOD TV and Orban are registered trademarks of AKG Acoustics Inc This manual is part number 95035 000 05C 150 FB 3 95 Copyright 1 995 orban H A Harman International...

Page 16: ...INE MAINTENANCE SYSTEM DESCRIPTION CIRCUIT DESCRIPTION USER ACCESS FIELD AUDIT OF PERFORMANCE PROCEDURE FIELD ALIGNMENT PROCEDURE TROUBLE DIAGNOSIS AND CORRECTION INTERFACING TO THE ORBAN 8185A NORMAL...

Page 17: ...R Output Mode 3 4 Fig 3 4 Card it 7 Output Format Jumper 3 4 Loudness Controller 3 4 Fig 3 5 Card it 2 Power Up 3 4 Fig 3 6 Deemphasis Jumpers 3 4 Other Jumpers 3 4 Reassembly INITIAL SETUP PROCEDURE...

Page 18: ...igh Frequency Limiter B 7 High Frequency Limiter Control Circuitry B 8 Peak Limiting System B 8 Clipper With Dynamic Threshold B 9 Hilbert Transform Clipper B ll 15kHz Phase Corrected Bandpass Filter...

Page 19: ...g IC Opamps F ll Selecting and Ordering Replacement Parts F ll Ordering Parts From the Factory F ll Replacement Of Components On Printed Circuit Cards F 13 Shipping Instructions F 13 Circuit Cards F 1...

Page 20: ...width limiting 15kHz lowpass filters incorporating full overshoot compensation OPTIMOD TV thus provides extremely tight control over peak modulation preventing overmodulation and controlling its outpu...

Page 21: ...wiring including the RFI filter card has been changed to accomodate stereo audio Since the stereo generator is omitted the STEREO MONO mode switch and indicator lamp have been excluded The rotary swit...

Page 22: ...Band Compressor at the studio side of the STL telephone line dual microwave or FM subcarrier on a video STL to protect the STL from overmodulation This configuration consists of an OPTIMOD TV Model 81...

Page 23: ...se since the amount of gain reduction varies widely with variations in program material and operator gain riding A GATING function is provided which prevents noise rush up during program pauses partic...

Page 24: ...dness of broadcast audio To estimate the perceived loudness the preemphasized outputs of OPTIMOD TV are summed deemphasized and fed into seven parallel filters covering the frequency range of approxim...

Page 25: ...avoidable overshoots in its integral 15kHz lowpass filter These overshoots must be eliminated without adding out of band frequency components This is done in the FCS Overshoot Corrector The FCS circui...

Page 26: ...ained by defeating exciter preemphasis and applying the preemphasized signal from OPTIMOD TV to the flat exciter However in some systems it is extremely inconvenient to defeat the exciter s preemphasi...

Page 27: ...l peaks by high frequency limiting distortion canceiling Hilbert transform clipping and bandlimited overshoot correction An interface connector for the Orban 8185A BTSC Stereo Generator is provided Th...

Page 28: ...ansmitter If not RF signal to noise ratio multipath distortion and diffraction effects can cause serious quality problems The 50 15 000Hz microwave system 2 provides more noise immunity than composite...

Page 29: ...me site or are connected by short high quality lines Because it is less expensive than the dual chassis version the single chassis version is also suited for use with any STL having extremely wide dyn...

Page 30: ...al exciters may not have separate subcarrier inputs In most cases one can be added simply by passively summing into the modulated oscillator through a resistor and small capacitor Note however that su...

Page 31: ...AGE CLAIMS MUST BE MADE BY YOU AGAINST THE CARRIER IMMEDIATELY UPON DISCOVERY Save packing and other evidence of damage for the carrier s inspector Set the unit on a flat soft surface Remove the three...

Page 32: ...andard characteristics then no modifications need to be made and you may skip to Reassembly below All modifications are made on the plug in circuit cards If the steps above regarding physical inspecti...

Page 33: ...ecause we feel that the overall broadcast system will work better with the filters operative for reasons discussed in detail in paragraphs l b and l c of Appendix A Some may disagree Those who wish to...

Page 34: ...m Cards 8 and it 9 It is shipped strapped for this condition When it is moved to an Accessory Chassis it must be restrapped according to Fig 3 6 below 6 Other Jumpers OPTIMOD TV shares circuit cards w...

Page 35: ...t rack space in the studio It is important to bear in mind that its RFI suppression is modest because it was assumed that the unit would be operated at a considerable distance from high powered transm...

Page 36: ...E THRESH control will be approximately 6dB higher than normal compressor dynamic performance will suffer slightly and the Loudness Controller threshold will be 6dB too high making the Loudness Control...

Page 37: ...transformers are suitable However most transformers will degrade the pulse response of the system and use of active input stages at the aural exciter or stereo generator is advised as discussed in Pa...

Page 38: ...cale is approximately 0 33V per dB of gain reduction and the source impedance is 8 87K A standard 0 25dB Orban gain reduction meter can be connected directly between this terminal and ground The Orban...

Page 39: ...from redundant sources the output may be taken from either the left or the right channel When driven with a 1kHz tone the Loudness Controller causes no additional gain reduction Therefore it may be i...

Page 40: ...dard land line requiring a nominal drive level of 8dBm simply turn the Accessory Chassis OUTPUT ATTEN fully clockwise If the STL is preemphasized at 50 or 75us adjust the Accessory Chassis OUTPUT ATTE...

Page 41: ...sis RIGHT OUTPUT ATTEN control until your TV Stereo Monitor indicates a L R modulation of 30 Check the reading of the Main Chassis R SYSTEM OUT meter It should be very close to the reading obtained on...

Page 42: ...parallel the left and right inputs until the procedure instructs you to do so In a stereo installation the procedure is repeated twice once for the left channel and once for the right There are three...

Page 43: ...LEFT INPUT of OPTIMOD TV Set its frequency to 1kHz and its output level to produce OdB 3dB as indicated on the TOTAL MASTER G R meter Connect the LEFT OPTIMOD TV OUTPUT to the input of the aural exci...

Page 44: ...Pj OPERATE OPERATE 0 comp UN PROOF 1 o LOUDNESS CONTROL 4 6 B O O io o io RIGHT LEFT INPUT ATTENUATOR Y w BASS COUPLING INDEPENDENT WIDEBAND BATE THRESHOLD OUTPUT ATTENUATOR Fig 4 5 RECOMMENDED INITIA...

Page 45: ...T OUTPUT is driving the aural exciter make slight adjustments to the LEFT OUTPUT ATTEN as necessary to achieve desired modulation levels As in the step above either load both outputs with equal impeda...

Page 46: ...ntrol Settings 5 7 Understanding More About Audio Processing 5 7 Some audio processing concepts 5 7 Gating for unobstrusive processing 5 8 Control of dynamic range gain reduction and release time 5 9...

Page 47: ...limiter Hilbert Trans form Clipper and FCS Overshoot Compensator when set to proof CLIPPING control adjusts signal level going into the Hilbert Transform clippers and therefore determines the amount...

Page 48: ...ndicates an extra 3dB peak limiting gain reduction over that indicated by the COMPRESSION meter which shows the amount of gain reduction resulting from slow compression in dB 0 on the COMPRESSION mete...

Page 49: ...erate with each other It is important that Engineering understand well the sound that Programming desires and that Management fully understand the trade offs involved in optimizing one parameter such...

Page 50: ...typical of conservatively processed popular music on FM radio These settings will produce quite consistent results from a wide variety of source material TYPE OF PROGRAMMING 8182A Audio Processor Cont...

Page 51: ...am level is still high enough to produce gain reduction For example to limit the amount of normal compression to 5dB instead of the usual lOdB adjust the GATE THRESHOLD control so that the gate indica...

Page 52: ...consistency between program segments but can also result in an unattractive busier flatter or denser sound It is important to be aware of the many negative subjective side effects of excessive densit...

Page 53: ...preserves the dynamic range of the source audio Higher levels of gain reduction are recommended for music videos programming to achieve an open yet reasonably consistent sound more typical of FM audi...

Page 54: ...pressor has run out of gain reduction range that the circuitry is being overloaded and that various nastinesses are likely to commence Because the compressor has a gain reduction range of 25dB the met...

Page 55: ...unt of clipping is increased the audible distortion caused by clipping is increased Lower settings yield less consistent loudness but result in the cleanest sound and best high frequency response In o...

Page 56: ...ency limiting will occur automatically In fact you will clearly hear a loss of highs when you adjust any control to produce more consistent loudness and greater density this is a result of the basic p...

Page 57: ...t 0 with fast release times Turn down CLIPPING and HF LIMITING as necessary to avoid objectionable distortion 2 Clean up audio Super clean audio can be processed harder without objectionable side effe...

Page 58: ...ial in production To obtain a heavily processed sound 1 Operate the RELEASE TIME control at 0 and the BASS COUPLING control at 0 You may have to back off the CLIPPING and HF LIMITING controls to avoid...

Page 59: ...rately reflect the noise performance of the system under normal operating conditions provided that the system is normally adjusted to run with lOdB gain reduction Only the poorest quality STL links wi...

Page 60: ...need to readjust the 8182A s OUTPUT ATTENUATORS to achieve 100 L R or L R L R at up to 100 modulation can be generated by driving both Left and Right channels in phase while L R at up to 100 modulati...

Page 61: ...anel wash it with a mild household detergent and water Stronger solvents may damage plastic parts paint or the silkscreened lettering and should not be used ROUTINE This procedure can be performed ver...

Page 62: ...meter position causes the meter to read OVU 1 0VU 5 Repeat steps 3 and 4 for the RIGHT channel 6 Restore the OPTIMOD TV setup controls to their normal settings Failure to produce these standard levels...