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LEVEL 
MAGIC 

 

Introduction & Reference guide

 

d06 d07 b46 C8007 C8046

 

 

The 

transient processor

 immediately reduces or raises the level of a new program part 

so that level jumps over 10…12dB are eliminated.  

 

 

A compressor/limiter combination of a known dynamics processor by Junger Audio is 
always controlling the audio level in relation to the limiter threshold. In result no 
headroom is more existing and the signal is developed to reach a 100% output level. 
This characteristic is useful to reach maximum levelling for audio disk mastering as 
well as to reach 100% modulation for FM transmitters.  

 

 

In compare to that Level Magic™ is serving two different levels – operating level and 
peak level. Between operating and peak level we will find the so called “headroom” for 
peaks that are still coming with the audio signal, even if this is level controlled related 
to the operating level. Level Magic™ is a unique algorithm to make automated audio 
level control possible. It is a combination of an adaptive AGC (automated gain control) 
with a transient processor and a brickwall limiter. The combination of an AGC circuit 
with a transient processor is the key to get a satisfying output level control for any kind 
of input level changes.  
 
 

 
 
 
 
 

 

 

3dB level difference 

9dB level difference 

Input level change 
The picture is showing a theoretical level change 
of +5dB and –5dB around operating level. 

 

 

What makes the

 Level Magic

 different from previous dynamics processors? 

 

Summary of Contents for d07

Page 1: ...digital transmission processor d07 release 4 1 ...

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Page 3: ...hich is unique in its design and specification Please read this manual carefully to ensure you have all the information you need to use the d07 The unit was manufactured to the highest industrial standards and went through extensive quality control checks before it was supplied If you have any comments or questions about installing setting up or using the please do not hesitate to contact us d07 ...

Page 4: ...e Control 2 9 LAN interface optional 3 Location of parts and controls 3 1 Front panel 3 2 Rear panel 3 3 Switches and jumpers for configuration 4 Operation 4 1 Front panel operation d07 keys 4 1 1 Navigation 4 1 2 Main Display 4 1 3 Menu Preset Setup 4 1 4 Factory presets 4 1 5 User presets 4 2 Operation via web interface 4 2 1 web interface of the d07 4 2 2 Maintenance 4 2 3 DATA transfer 5 Boot ...

Page 5: ...rocessor Principle 2 The Junger Audio Compressor Expander Principle 3 The Junger Audio Processing Presets 4 LEVEL MAGIC 5 GUI 6 Network Integration for TCP IP Operation 7 FM Processing d07 7 1 General 7 2 MPX Limiting 7 3 Pre emphasis 7 4 Terms and definitions ...

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Page 7: ... by the AGC and the Transient processor and the peak Level for the Brickwall Limiter In both operating methods you can factor the adaptive pre emphasis the maximum value for the peak frequency deviation and the MPX Limiter into levelling of the signal see application notes The dynamic range processor principles developed by Junger Audio enable level managing devices like compressors AGC and limite...

Page 8: ...dio signal processing also in consideration of pre emphasis and MPX Power Digital I Os AES EBU format 24bit ADV and DAC Stereo and dual channel mode Parallel and serial remote control Equal functionalitiy to the processor C8007 of the C8000 modular system 1 2 BLOCK DIAGRAM Further description of the processor principles see Application notes B ...

Page 9: ...e connecting the digital audio level processor d07 switch the power off at all connected units The digital audio level processor d07 is made as standard 19 unit EIA format It occupies 1 RU 44 mm height space in a rack Please allow at least additional 3 depth for the connectors on the rear panel When installing the unit in a 19 rack the rear side of the unit needs some support especially for mounti...

Page 10: ...ks with black burst at sync input internal 48 kHz Digital inputs are connected via sample rate converter The analog audio inputs are RFI filtered and analogue outputs are balanced and floating like transformer coupled devices All the audio connectors are via rear panel mounted connectors Standard XLR connectors are used These are always wired to the AES standard pin 1 X Screen screen pin 2 L Live ...

Page 11: ...onfig 9 5V 110Ohm 10 GPI1 GPI2 common 11 GPI3 common 12 GPI4 common 13 GPI5 common 14 GPI6 common 15 GPI7 GPI8 common Shield GND Electrical specification GPI input potential free by opto coupler witt current source OFF 3 5 30V between GPIx input and GPx common ON less then 1 5V betwee GPIx input And GPIx common signal duration 3 5 30V for at least 50msec Note An internal auxiliary voltage feed is ...

Page 12: ...110 Ohm 14 TALLY 1 common 15 Tally 2 normally closed 16 Tally 2 normally opened Defined by d07 config 17 TALLY 3 common 18 Tally 4 normally closed 19 Tally 4 normally opened Defined by d07 config 20 TALLY 5 common 21 Tally 6 normally closed 22 Tally 6 normally opened Defined by d07 config 23 TALLY 7 common 24 Tally 8 normally closed 25 Tally 8 normally opened Defined by d07 config Shiled Electrica...

Page 13: ...ment in CAN bus mode Pin Signal name Functions 1 NC Not used 2 CAN l CAN bus low signal 3 NC Not used 4 NC Not used 5 GND Ground 6 GND Ground 7 CAN H CAN bus high signal 8 NC Not used 9 NC Not used This connector has multiple functions which may be internally changed by connectors and jumpers The factory default format setting is RS232 and the it is connected with the serial interface of the LAN C...

Page 14: ...tions 100Mbit s auto negotiation port Application remarks This port allows the remote control of the d07 by TCP IP over Ethernet Setting up the network configuration is described in B 6 The LAN Controller of the d07 has a web server which offers a graphical user interface GUI For proper operation you need IE7 or FireFox 2 0 There you input the IP address of the d07 as an URL d07 control block diag...

Page 15: ...ge of Leveller AGC transient processor Compressor without Level Magic Peak Lim MPX Lim Output Level MPX Power 3 1 FRONT PANNEL 3 2 REAR PANNEL Analog I O Analog level adjustment GPI 15 pin female connector EXTERNAL SYNC IN Word clock Video AES WORDCLOCK OUT REMOTE INTERFACES 9 pin Female connector RRS 232 CAN RJ 45 connector Ethernet Digital I O AES EBU Tally out 25 pin female ...

Page 16: ... for AES EBU standard format connector XLR male panel jack ANALOG IN OUT Analog input to 24 bit A D converter Input floating balanced XLR connector female Analog output from 24 bit D A converter Output floating balanced XLR connector m Some basic settings can be made by switches and jumpers at the internal circuit boards of the unit These settings can occur general changes for operation and should...

Page 17: ...o change the setting to another standard you just have to slide this dip switch to the right OFF and slide the needed dip switch that corresponds to the reference standard you are using to the left ON Æ Make sure that there is always just ONE dip switch turned ON Exception They may all be OFF if you are using a CUSTOM reference level CUSTOM Refernce Level using Switch 6 ADJ If none of these stansa...

Page 18: ...e the digital output Make sure that the DSP processing is bypassed otherwise there could be DSP gain active 3 When the adjustments are complete capture the custom settings by setting dip switch 6 to OFF Otherwise your reference level could be changed by accident at the potentiometers rear of the box This should only be done by experienced engineers with measuring instruments After having adjusted ...

Page 19: ...vice All changes to a parameter are effective immediately Pressing ENTER will approve it By pressing ESC the changes will be rejected and the display returns to the parameter menu Loading of a PRESET will immediately carry over the values into the operating memory By clicking free cross fade they will be effective immediately There is the possibility to edit and store PRESETs in the back ground wi...

Page 20: ... actual MPX Power of the output signal AGC 0 0 dB Instantaneous value of the AGC gain BAL R 0 0dB The chart on the following pages gives an overview over the menu structure its parameters and the available ranges Menu item Value range Description PRESET LOAD PRESET Preset 1 4 User presets TV U TV universal R U Radio universal R SP Radio Sports TV L TV live TV M TV movie R CL Radio classic EDIT PRE...

Page 21: ...them SYNC Video Wclk Ext AES Input AES INT 44 1 INT 48 Selection of the SYNC source PARAMETER GAIN 20 to 20dB Setting the initial gain STEREO OFF ON For stereo operation with the d07 the control circuits of the dynamic sections can be linked FILTER 30Hz OFF ON Switching off on 30Hz low cut filter 15kHz OFF ON Switching off on 15kHz FIR Filter PREEMPHASIS PRE MODE OFF 50µs 75µ The d07 controls high...

Page 22: ...fter appr 20 seconds input level below silence gate the current gain change is slowly moving to the longterm average gain LEV TIME AGC time 10s 2h Describes the time of development for the AGC to reach the maximum possible gain change range value The ratio of gain change should never be faster then 3 seconds for 1 dB We are recommending a setting of 4 5 seconds for 1dB gain change by the AGC There...

Page 23: ...0 0 0 0 0 0 0 0 0 0 0 0 PEAK LIMITER LIM THRESH 0 0 9 0 0 0 0 0 9 0 9 0 0 0 LIM PROG uni uni uni speech live uni classic MPX LIMITER MPX POWER off off off off off off off EXPANDER EXP THRESH off off off off off off off EXP RANGE off off off off off off off EXP ATTACK 0 5 0 5 0 5 0 5 0 5 0 5 0 5 AUTO BALANCE BAL RANGE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 BAL TIME 1min 1min 1min 1min 1min 1min 1min LEVEL MAG...

Page 24: ...8 PARAMETER GAIN 0 0 STEREO off FILTER 30Hz off 15kHz off PREEMPHASIS PRE MODE off PRE THRES 0 0 PEAK LIMITER LIM THRESH 0 0 LIM PROG uni MPX LIMITER MPX POWER off EXPANDER EXP THRESH off EXP RANGE off EXP ATTACK 0 5 AUTO BALANCE BAL RANGE 0 0 BAL TIME 1min LEVEL MAGIC ON LEVELLER OPERATING LEVEL 0 TR P RANGE 0 TP PROG Soft SILENCE GATE AGC gate 40 LEV TIME AGC time 1 min LEV RANGE AGC range 0 LEV...

Page 25: ...ily via web browser See chapter B6 Network integration Just type the valid IP address of your device into your web browser http IP address You will get the following page 4 2 2 Maintenance Device related settings web interface controller related settings 4 2 Operation via web browser Device related settings Parameters of the device are described in 4 1 3 ...

Page 26: ...ates for the controller of the device This update will be automatically offered when you go to the GLOBAL page of the d07 module Reboot controller Rebooting the device activates the changes you have made to the network configuration If you have changed the IP address of the device you are not able to reach the web interface after the reboot You have to use the new address of course 4 2 3 DATA tran...

Page 27: ...ftware version D x x display of loaded dsp software version display error message remedies SYNC ERROR no sync at sync input connect the sync input selectable in SYNC field with valid input signal INPUT sync on DIGITAL IN CH 1 2 EXT AES sync on SYNC AES EBU EXT VIDEO sync on SYNC VIDEO EXT WCLK sync on word clock 5 1 BOOT DISPLAY 5 2 ERROR MESSAGES AND TROUBLE SHOOTING A 5 ...

Page 28: ... setup and the program is restarted Any button exceptional MENU Peak up is to be held pressed in order to initialize the device during power on of the device until the program has started To the start of the program and at the completion of the displays how described in 6 1 the device is ready for operation with the factory setup After an initialization of the device all user presets and adjustmen...

Page 29: ... IN Resolution 24bit sample rate 44 1 48kHz dynamic range 110dB RMS 114dB A weighted THD N 0 002 max input level frequency response 20Hz 20kHz FS 48kHz 0 5dB CMRR 100dB 50Hz max input level 22dBu 0dBFS input impedance 10 kOhm floating balanced connector XLR 1 screen 2 live 3 return ANALOG OUT Resolution 24bit sample rate 44 1 48kHz dynamic range 108dB RMS 110dB A weighted THD N 0 002 max input lev...

Page 30: ...deo WCLK OUT WCLK connector BNC 10kOhm coaxial level TTL level output format Wordclock REMOTE serial remote interface RS 232 in out connector 9 pin SUB D female serial remote interface RS 422 connector 9 pin SUB D male optional TCP IP GPI parallel remote level opto coupler 3 24V control voltage connector 15 pin SUB D female Tally Out level relais contact connector 25 pin SUB D female power consump...

Page 31: ...s Processor Principle 2 The Junger Audio Compressor Expander Principle 3 The Junger Audio Processing Presets 4 LEVEL MAGIC 5 GUI 6 Network Configuration for TCP IP Operation 7 FM Transmission d07 7 1 General 7 2 MPX Limiter 7 3 Pre emphasis 7 4 terms and definitions B ...

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Page 33: ... attack time and one release time They must be adjusted manually by the user to optimal settings for processing with as little disturbance as possible through a process of trial and error A lot of experience and a lot of time is necessary to get acceptable results These settings once found are only the right choice for a certain program signal and must be changed for other program types Multi band...

Page 34: ...of direct signals should therefore be carried out before mixing them with delayed processed signals Adaptive Dynamic Range Control The proprietary algorithms in the Junger System also allow the automatic adjustment of the attack and release times according to the evolution of the input signal over time This is called Adaptive Dynamic Range Control By monitoring the waveform of the incoming audio t...

Page 35: ... applied is reduced Please see the figure to the right Dynamic structures of the entire range of the input signal amplitude are converted proportionally Even after compression the dynamics of incoming audio are maintained only slightly condensed leaving a transparent seemingly uncompressed sound impression The gain of the compressor called range can be limited from 1 dB to 15dB to prevent unaccept...

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Page 37: ...st each kind of program material The algorithm has to guarantee best reaction for fast increasing level of transient signals anytime even if classical music with slow dieing out characteristic is processed In all cases the attack time of the limiter for very short transients is zero Especially the release time of the control circuit has more influence to the increase of loudness as any other param...

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Page 39: ...B 4 LEVEL MAGIC LEVEL MAGIC B 4 ...

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Page 41: ...LEVEL MAGIC 1 Release 2005 Junger Audio Berlin Introduction Reference guide TM ...

Page 42: ...ss of the source without touching the sound of the audio material No breathing no pumping no spectral changes Just well controlled dynamics Unpleasant level jumps are eliminated Level changes from different feeds level differences between different program parts or even loudness problems in broadcasting Level Magic will take care of them automatically with a result the Listener will want to hear M...

Page 43: ...ts this is done by the Transient Processor 2 Level jumps rising over a certain absolute value are very unpleasant for our ears Of course it depends on the type of audio material and consequently on its loudness which absolute value of level change really annoys A jumping level of 6dB is remarkable A quick level change of 10 12dB becomes annoying for the human ear So it s necessary to avoid major l...

Page 44: ...ic is serving two different levels operating level and peak level Between operating and peak level we will find the so called headroom for peaks that are still coming with the audio signal even if this is level controlled related to the operating level Level Magic is a unique algorithm to make automated audio level control possible It is a combination of an adaptive AGC automated gain control with...

Page 45: ...Transient Processor Transient processor is doing fast gain change and the AGC is doing slow gain change depending on settings Always the AGC should be set in a way that the gain change is mostly inaudible 1dB per 5 seconds or slower The Transient Processor should be set that incoming level jumps are reduced but originally dynamic range is not changed too much As more possible gain by the Transient...

Page 46: ...n change of the AGC freezes immediately Transient processor is still active After appr 20 seconds input level below silence gate the current gain change is slowly moving to the longterm average gain Transient program soft mid hard This parameter describes the characteristic of gain change by the transient processor It has to be chosen dependent on your program genre If there are just a few level c...

Page 47: ...ntrol is As less available maximum gain by the transient processor as more sensible the level control will be applied Because of the use of adaptive controlled processing algorithms and considering the fact that the AGC setting must meet the slow gain change requirement just a few variations are left Mostly changeable parameters to play with are Transient Processor Range in accordance with Transie...

Page 48: ...9dBFS 9dBFS 18dBFS AGC Range 10dB 15dB 10dB 10dB 10dB 10dB AGC Gate 60dBFS 50dBFS 50dBFS 40dBFS 50dBFS 50dBFS AGC Time 2min 2min 20s 20s 40s 40s Transient Program Soft Mid Hard Hard Mid Mid Transient Range 3dB 6dB 10dB 15dB 10dB 10dB LIMITER ON ON ON ON ON ON LIMITER Threshold 0dBFS 9dBFS 9dBFS 0dBFS 0dBFS 9dBFS LIMITER Program 6 4 1 2 4 4 Max total gain change 13dB 21dB 20dB 25dB 20dB 20dB Overvi...

Page 49: ...B 5 GUI software for d07 GUI software for d07 B 5 ...

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Page 51: ...C8007control software window 4 1 4 2 TCP IP set up 4 1 4 3 Loading saving files 4 3 4 4 Selecting devices 4 3 4 5 Controlling the data flow 4 5 4 6 Parameter editing 4 6 4 6 1 Function button 4 7 4 6 2 Drag label 4 7 4 7 Load presets 4 7 4 8 Save presets 4 8 4 9 Edit presets off line 4 8 4 10 Device set up 4 9 5 End User Licence Agreement 5 1 Justus von Liebig Straße 7 12489 Berlin Germany Telefon...

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Page 53: ...ata on the PCs HD 1 3 OFFLINE EDITING OF PARAMETERS If the soft button CONNECT is turned off black letters you are off line in other words disconnected from a pre selected device Now you will be able to change processing parameters without effecting the actual processing edit setup parameters edit preset data store preset data and hardware setup data on the PCs HD 1 4 DATA TRANSFER Connecting reco...

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Page 55: ...nterfaces available from the GUI but we will not support them any longer The interface for use is TCP IP This decision will also make software distribution and installation much easier because we do not need to modify your system by special drivers DLPORTIO DLL SYS INSTALLATION OF THE C8007control SOFTWARE The software will be delivered on CDROM on request or will be available for download from ww...

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Page 57: ...AN to be available for the C8007control software that runs on a PC OS WXP recommended with access to this network Normally you can run only one application on a PC For special needs there is the C8007_2x exe that will launch two applications on a PC the so called double pack You can run as many PCs with a C8007control application within the network as you like The only limitation is that only up t...

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Page 59: ...es You should overwrite the DUMMY entry with a valid IP address from your system A Server can either be the C8k system controller C8702 or the built in Ethernet controller of a d07 Please refer to the respective manual for integrating such a device into your LAN The Scan Min Max values are relevant for C8k systems with extended CAN bus or distributed module addresses where you need to scan a lot o...

Page 60: ...ded into several sections On the top you will find the MS Windows menu bar From there you can load and store files select the physical interface of the PC TCP IP select two operation options and set up TCP IP There is no on line Help menu available only the submenu About The About window shows some system information such as PC OS device hardware information and the DSP as well as the controller f...

Page 61: ...nder control It is also possible to save these settings by File Save This dialog will also be used when saving device parameters from a connected device This dialogue gives you the device name as a default file name 4 4 SELECTING DEVICES In bigger installations there are two steps to select a device First you must select one controller server from the many you have in your system When you have sel...

Page 62: ...as the d07 Ethernet interface are talking internally via the CAN bus with the physical processing device s In a C8k system the devices are the processing modules C8007 while the d07 is treated as one device with almost the same behaviour as the C8007 For a d07 there is only one device Therefore you do not need to make a selection ...

Page 63: ...depends on the Scan Min Max values of the Setup TCP IP menu see page 4 1 CONNECT Will connect the GUI with a selected device on demand or reconnect it with the previous selected device The parameters will be downloaded from the device This action will overwrite the data of the GUI There is an option Connect Automatically After Scan If it is checked the application will automatically connect with t...

Page 64: ...hecked the parameters which are displayed will be overwritten from the on air data of a file when you perform a File Load the active data of the device on air parameters will be overwritten when you perform an UPLOAD COPY Copies the parameters from the on air processing i e displayed by the GUI to a clip board PASTE Transfers the parameters from the clip board into the on air processing of the sel...

Page 65: ...RAG LABEL is a GUI tool to adjust the related parameter The parameter value is displayed numerically and by a bar within the label For doing changes of parameters you must bring the mouse cursor over the label Holding down the left mouse button and moving the mouse horizontally will change the value in fine steps but slowly Holding down the right mouse button will change the value in big steps but...

Page 66: ...ange the name of the preset If you do not want to change it simply press ENTER and you are finished 4 9 EDIT PRESETS OFF LINE When you press the EDIT soft button the application will be disconnected from the device and the GUI will open this window Now you can load a preset from the devices memory into the GUI and make changes to the parameters by using the drag labels This action takes place in t...

Page 67: ...not the name i e the name of the preset where you store the data will be preserved If you want to edit the preset name you must load that preset Now you must click into the preset name field and change the name of that preset press ENTER to end the edit function of the name Finally you must press SAVE TP Px or SAVE EXIT You can abandon the off line edit mode by pressing ESCAPE 4 10 DEVICE SET UP W...

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Page 69: ...computers over an internal network however you must acquire and dedicate a license for each separate computer on which the SOFTWARE is installed or run from the storage device A license for the SOFTWARE may not be shared or used concurrently on different computers 2 RESTRICTIONS You must maintain all copyright notices on all copies of the SOFTWARE Limitations of Reverse Engineering Decompilation a...

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Page 71: ...t network configuration of the Jünger devices is IP Address on a label at the Ethernet connector socket at the rear of the device Netmask 255 255 0 0 Gateway 10 110 0 1 1 Integration into existing LAN When you want to integrate the device into an existing LAN you have to change its IP address the sub network mask and the gateway You will get valid settings from your network administrator You can d...

Page 72: ...d 1 to 1 to your PC Start your terminal program e g Start Programs Accesoires Communications HyperTerminal Enter a name of your choice and press OK Choose the connection port you are working with and press OK Set the COM settings as they are shown in the window above and press OK ...

Page 73: ... default IP address and network configuration will be active again In case of need you can read the default IP address always on the controller in the device B You can also change the IP address of the device over Ethernet connection Disconnect your PC from the LAN connect it to the device directly via Ethernet crossover cable not connected 1 to 1 but 1 to 8 etc Change the network configuration of...

Page 74: ...ROPERTIES In this example the Ethernet TCP IP is set to Obtain an IP address automatically If in your case it is set to Use the following IP address jot down the current settings on a piece of paper IP address Subnet Mask and Default gateway if used You will need them later to restore the IP address of the PC to what it is required to work on your LAN ...

Page 75: ...o take 10 110 123 115 as IP adress or something near to the device s address only 10 110 123 have to be the same and the same netmask The gateway is not important when you are using an Ethernet crossover cable When you have changed the settings press OK Now you will be able to communicate from PC to device via web browser e g internet explorer with an Ethernet crossover cable Just type in the devi...

Page 76: ... LAN you want to use Then you will be able to communicate with the device over web browser via the chosen IP address 2 Connection via Ethernet crossover cable When you want to communicate with the device via Ethernet crossover cable you can C change your PC network settings and match them to those of the device OR D keep your PC network settings and change the ones of your device C to change the P...

Page 77: ... cause the permissible value of the multiplex power to be exceeded and the MPX limiter must reduce the total signal As a consequence the peak levels as well as the average levels are reduced leading to a reduced loudness as outlined below Input signal compressor out peak limiter out MPX limiter out peak level MPX level Compressor Peak limiter MPX limiter Input Oputput peak reduction MPX power redu...

Page 78: ... 0dBr lies 11 1 dB below the limitation point of the limiter of the d07 and is fixed to it This value is given by the relation of multiplex power level of 0dBr 19kHz frequency deviation to peak level 75kHz frequency deviation For special applications the MPX level can be changed by 4dB respectively The operating level in standard studio environment is not the peak level but the nominal level of 6d...

Page 79: ...peak deviation If the program material has a lot of high frequency components the activity of the adaptive filter is of course more frequent and will eventually be audible If the threshold of the peak limiter is not set to maximum but some dB s below the resulting headroom can be used for higher frequency components The operation of the adaptive pre emphasis filter also happens in this case only w...

Page 80: ...m B B B 2Δfc 2Δfc 2Δfc 2Δfc 2Δfc 2Δfc B 2 Δfc fm You can show that a bandwidth of approx B 2 Δfc max fm max is needed for FM modulation for high rejection of high frequency signals With a maximum frequency deviation of 75kHz and 15kHz cut off frequency of the modulating signal B will be 180kHz Based on this fact the planning of transmitter positions and power takes place for area wide feed To prev...

Page 81: ... be avoided s a pre emphasis MPX Spektrum 38 23 19 15 53 Differential signal L R S Auxiliary carrier pilot ton Illustration of base band spectrum of a MPX signals Frequenz in kHz Compatible monaural signal L R M Spectrum of MPX signals Double sideband suppressed carrier power of the M signal proportional to the square of the amplitude of the M signal PM M2 power of the S signal proportional to the...

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