Tektronix 070-8811-08 manuale d’uso

User Manual 764 Digital Audio Monitor (Serial Number B020000 and Above) 070-881 1-08 This document supports firmware version 2.1 and above. www .tektronix.com[...]

Copyright © T ektronix, Inc. All rights reserved. T ektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes that in all previously published material. Specifications and price change privileges reserved. T ektronix, Inc., P .O. Box 500, Beaverton, OR 97077 TEKTRONIX and TEK are regi[...]

W arranty T ektronix warrants that the 764 Digital Audio Monitor will be free from defects in materials and workmanship for a period of one (1) year from the date of shipment. If any such product proves defective during this warranty period, T ektronix, at its option, either will repair the defective product without charge for parts and labor , or [...]

764 Digital Audio Monitor User Manual i T able of Contents General Safety Summary vii . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preface xi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . This Manual xi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Contacting T[...]

T able of Contents ii 764 Digital Audio Monitor User Manual Features of the Session Display 29 . . . . . . . . . . . . . . . . . . . . . Session Statistics 30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Session Reports 34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The Channel Status V iew 37 . . . . [...]

Contents 764 Digital Audio Monitor User Manual iii Operating Information 90 . . . . . . . . . . . . . . . . . . . . . . . . . . . . Changes to the Session Statistics Display 92 . . . . . . . . . . . . . Additional Error/W arning Messages 92 . . . . . . . . . . . . . . . . . Analog Line Output (Option 02) 93 . . . . . . . . . . . . . . . . . . . . .[...]

T able of Contents iv 764 Digital Audio Monitor User Manual Figure 21: The 764 phase display 27 . . . . . . . . . . . . . . . . . . . . . . Figure 22: The phase correlation meter 28 . . . . . . . . . . . . . . . . . Figure 23: The 764 AUDIO/SESSION view 29 . . . . . . . . . . . . . Figure 24: The SYNC ERR Flags 32 . . . . . . . . . . . . . . . . . [...]

Contents 764 Digital Audio Monitor User Manual v T able 8: Option 01 input submenu, video inputs selected 57 . . . T able 9: Time Code submenu 57 . . . . . . . . . . . . . . . . . . . . . . . . T able 10: Serial Port submenu items 58 . . . . . . . . . . . . . . . . . . . T able 1 1: Save Setups submenu 59 . . . . . . . . . . . . . . . . . . . . . .[...]

T able of Contents vi 764 Digital Audio Monitor User Manual[...]

764 Digital Audio Monitor User Manual vii General Safety Summary Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it. T o avoid potential hazards, use this product only as specified. Only qualified personnel should perform service pr ocedur es. T o A void Fire or Personal Injury[...]

General Safety Summary viii 764 Digital Audio Monitor User Manual Use in a Proper Environment Do not operate this product in wet/damp locations/conditions or in explosive atmospheres. Observe All T erminal Ratings T o avoid fire or shock hazard, observe all ratings and markings on the product. Consult the product manual for further ratings informat[...]

General Safety Summary 764 Digital Audio Monitor User Manual ix Symbols on the Product The following symbols may appear on the product: DANGER High V oltage Protective Ground (Earth) T erminal A TTENTION Refer to Manual Double Insulated[...]

General Safety Summary x 764 Digital Audio Monitor User Manual[...]

764 Digital Audio Monitor User Manual xi Preface The T ektronix 764 Digital Audio Monitor shown in Figure 1 is a tool for monitoring the signal levels and stereo phase of digitally-encoded (AES/EBU and IEC 958 “ consumer use ” ) audio in a production environment. The instrument can simultaneously display the levels of two two-channel inputs, an[...]

Preface xii 764 Digital Audio Monitor User Manual H Operating Basics — What you ’ ll need to know for day-to-day operation of the 764. Begins on page 13. H Refer ence — Begins on page 43. H Appendices — Instrument characteristics; Options/Accessories; User Service. Begin on page 75. H Glossary — Begins on page 101. H Index — Begins on p[...]

764 Digital Audio Monitor User Manual 1 Getting Started This section contains information you ’ ll need to put your 764 Digital Audio Monitor into service. For a detailed description of instrument capabilities, and instructions for its use, refer to the Operating Basics section of this manual. Unpacking Please save the packaging material in case [...]

Getting Started 2 764 Digital Audio Monitor User Manual Order the appropriate enclosure through your nearest T ektronix field office or representative. W ARNING. Do not carry an instrument in one of the optional enclosur es without first installing the cabinet mounting scr ews as shown in Figur e 2. W ithout the mounting scr ews, an instrument can [...]

Getting Started 764 Digital Audio Monitor User Manual 3 Figure 3: The 764 rear panel and connectors (1) Digital Audio Inputs and Loop-Throughs The 764 has two, two-channel digital audio inputs, one labeled CH 1 – 2, and the other labeled CH 3 – 4. Each input in the standard instrument has two passive loop-throughs that allow you to switch the i[...]

Getting Started 4 764 Digital Audio Monitor User Manual NOTE . The male XLR connectors of instruments equipped with Option 02 (Analog Line Output) ar e labeled ANALOG OUT ; these instruments do not have pr ovision for loop-thr ough on the balanced XLR connectors. The balanced XLR inputs of Option 02 instruments ar e unterminated when the associated[...]

Getting Started 764 Digital Audio Monitor User Manual 5 NOTE . The balanced (XLR) loop-thr oughs ar e the default 764 inputs. T o r eceive a signal thr ough the unbalanced (BNC) loop-thr oughs or the optional serial video loop-thr ough (Option 01), you must first r econfigur e the instrument thr ough the on-scr een menus. Refer to Initial Power Up [...]

Getting Started 6 764 Digital Audio Monitor User Manual VGA or SVGA Monitor T ektronix 764 Monitor From VGA VIDEO Output Figure 5: Using an external color monitor (5) RS-232 Communications Port Through the RS-232 port, you can: H Output a record of the input signal and program, either to an ASCII printer or a personal computer (see Figure 6) runnin[...]

Getting Started 764 Digital Audio Monitor User Manual 7 T ektronix 764 Monitor Printer Computer Via RS-232 Print or Store Figure 6: Outputting a session report (6) Optional Serial Video Loop-Through Instruments equipped with Option 01 (Embedded Audio Input) have two additional 75 Ω BNC connectors, SER. VIDEO IN and SER. VIDEO OUT . These connecto[...]

Getting Started 8 764 Digital Audio Monitor User Manual Figure 7: The headphone output (schematic) By factory default, the headphone output automatically follows the phase display; that is, it contains the audio programs decoded from the two channels that you are monitoring with the Lissajous pattern and correlation meter . Y ou may also choose to [...]

Getting Started 764 Digital Audio Monitor User Manual 9 Initial Power Up and Configuration Once you have connected a signal source to at least one of the 764 DIGIT AL AUDIO inputs, switch the instrument On. When the start-up diagnostics are completed, the instrument will begin operation in the Audio V iew/Session display . If a signal source is con[...]

Getting Started 10 764 Digital Audio Monitor User Manual Perform the following steps to select the input types and familiarize yourself with the 764 menu structure: 1. Press the MENU button to enter the TOP MENU. 2. When the 764 is in menu mode, MENU provides access to context-sensitive HELP messages. Press MENU now to see the TOP MENU help message[...]

Getting Started 764 Digital Audio Monitor User Manual 11 Figure 10: Selecting from the top menu 4. The five buttons immediately to the right of the display are called soft buttons. The printed/molded lines to the left of these buttons serve to associate the buttons with on-screen menu choices or functions. In Figure 10, the bottom soft button is as[...]

Getting Started 12 764 Digital Audio Monitor User Manual Figure 1 1: The inputs submenu 6. T urn the multi-function knob to move the menu highlight to the “ CH 3 – 4 input: ” line. 7. If desired, change the channel 3 – 4 input to the BNC connector by pressing the associated soft button. 8. Press the CLEAR MENU button to exit the menus and r[...]

764 Digital Audio Monitor User Manual 13 Operating Basics This section contains the basic information needed to use your 764. The subsections are: Overview , Front Panel Controls, The Level Meters, The Phase Display , The Session Display , Session Reports, The Channel Status V iew , The User Data V iew , and Other Features. Please take a few minute[...]

Operating Basics 14 764 Digital Audio Monitor User Manual The left portion of the Audio view display always contains four “ bar graph ” level meters. The right portion contains either a numerical display of session statistics (see Figure 12), or the Phase display (shown in Figure 13). Configure the right side of the Audio view display with the [...]

Operating Basics 764 Digital Audio Monitor User Manual 15 without requiring constant operator attention. When errors and peaks are encountered, they are time-stamped with the active session time code, which makes it easy to return to the part of the program that contains the event of interest. See page 34 for more information. Figure 13: The 764 AU[...]

Operating Basics 16 764 Digital Audio Monitor User Manual menus), then the VIEW :USER DA T A button. Y ou may select a number of User Data view options with the Soft buttons. Refer to The User Data V iew beginning on page 39 for more information. Other Features W ith the 764, you can also save up to three instrument configurations (setups) for late[...]

Operating Basics 764 Digital Audio Monitor User Manual 17 The SESSION button selects a Session Statistics panel, illustrated in Figure 12. Refer to The Session Display beginning on page 29 for more information. Figure 14: 764 front-panel controls (4) METER SCALE buttons. Use the METER SCALE buttons to change the Audio view level meter scale. The de[...]

Operating Basics 18 764 Digital Audio Monitor User Manual LED immediately above the knob will light and a knob icon will appear in the upper -right of the display when the knob is active. (6) MENU button. Press MENU to invoke the display menu and call up context-sensitive help text when a menu is on screen. (7) Soft buttons. The five white soft but[...]

Operating Basics 764 Digital Audio Monitor User Manual 19 Figure 15: The 764 Level Meters (1) Meter Ballistics (i.e., dynamic response, or attack/decay character- istics of the meters). The meters can emulate the dynamic re- sponse of three common types of analog audio level meter . Choices are VU with the scale extended to permit display of true p[...]

Operating Basics 20 764 Digital Audio Monitor User Manual Figure 16: The sum and difference display modes (3) Peak Program level. The Peak Program level is usually the maxi- mum permissible level for audio program material. The default Peak Program level is – 8 dBFS; you may set it to the integer val- ue between 0 (FS) and – 30 dBFS that is app[...]

Operating Basics 764 Digital Audio Monitor User Manual 21 H Shape: The upper 20 dB of the scale is linear in dB; the scale is progressively compressed below – 20 dBFS. H The upper limit of the meter scale is the anchor for expansion and compression; that is, the top scale number remains the same when you expand or compress the scale. H The lower [...]

Operating Basics 22 764 Digital Audio Monitor User Manual Please be aware that although the peak indicators may reveal higher peaks than VU or PPM ballistics, the indicators do act on the same, processed data as the meters. If interpolation is ON, the peak indicators show peaks in the oversampled data, and these peaks may be higher than those in th[...]

Operating Basics 764 Digital Audio Monitor User Manual 23 Press METER SCALE:NORMAL to restore the default meter scale; to later restore the “ custom ” scale and offset, press METER SCALE:CUST OM . Figure 17: Creating a custom meter scale Level Meter Submenu selections. All remaining level meter configura- tion selections are made through the Le[...]

Operating Basics 24 764 Digital Audio Monitor User Manual Figure 18: The Level Meters submenu 5. Again, use the multi-function knob to scroll the menu highlight to the parameter you wish to configure. The soft button assignments will change to reflect your choice of settings. For menu items that have numeric settings, the top two soft buttons becom[...]

Operating Basics 764 Digital Audio Monitor User Manual 25 the button down — or until you reach an adjustment limit.) Changes are confirmed by changed text after the parameter name in the submenu column on the left side of the screen. 7. Repeat steps (5) and (6) until you have configured the meters to suit your needs. 8. Press the TOP MENU soft bu[...]

Operating Basics 26 764 Digital Audio Monitor User Manual Figure 20: Sum and difference bars and the session display The Phase Display The 764 Phase display is a Lissajous pattern display augmented with a (phase) Correlation meter . It is designed for convenient, qualitative monitoring of the phase relationship between any two input channels. The P[...]

Operating Basics 764 Digital Audio Monitor User Manual 27 Figure 21: The 764 phase display The Lissajous Pattern The Lissajous portion of the phase display is a plot of one channel against another on an orthogonal pair of axes. The X – Y orienta- tion — shown on the right in Figure 21 — plots left channel data along the vertical axis and righ[...]

Operating Basics 28 764 Digital Audio Monitor User Manual +1 when the channels contain identical signals (frequency and phase); it will measure – 1 when the signals have the same frequency (or frequencies), but are 180 degrees out of phase. A center -scale (0) reading indicates uncorrelated — or random — signals. Figure 22: The phase correlat[...]

Operating Basics 764 Digital Audio Monitor User Manual 29 The Session Display The session display is a dynamic readout of session history; it is illustrated in Figure 23. When the 764 is in Audio view , press the PHASE DISPLA Y : SESSION button to toggle between the Phase display and the Session display . Figure 23: The 764 AUDIO/SESSION view Featu[...]

Operating Basics 30 764 Digital Audio Monitor User Manual Session time. The instrument time-stamps any errors encountered during the Session with the chosen time code; the information is saved in NVRAM for use when you output a Session report (refer to page 34). (2) Run(ning)/Stop(ped) indicator and soft button assignment. This indicator is associa[...]

Operating Basics 764 Digital Audio Monitor User Manual 31 H Number of CLIPs detected during the session. This is directly affected by the “ Consecutive FS Samples for CLIP ” setting in the Level Meters submenu. H Number of MUTEs detected during the session. Affected by the “ Consecutive ‘ 0 ’ Samples for Mute ” setting in the Level Mete[...]

Operating Basics 32 764 Digital Audio Monitor User Manual SYNC ERR flags as shown in Figure 24. Please see the following paragraphs for more information. Figure 24: The SYNC ERR Flags H Frame Synchronization Error — for each input with respect to the Digital Audio Reference (DAR), when one is present at the REFERENCE input. Otherwise — when bot[...]

Operating Basics 764 Digital Audio Monitor User Manual 33 displays under the meter bars of the unsynchronized input. Figure 24 shows the flags as they would appear if each input signal preceded or followed the DAR signal by more than 25% of a frame. The SYNC ERR flags also appear when the input signal sample frequency varies from the reference freq[...]

Operating Basics 34 764 Digital Audio Monitor User Manual Session Reports The 764 can output the data collected during a session — in the form of ASCII text session Reports, through the rear -panel RS-232 connector . Y ou can print reports on a serial printer , or save them to files on an IBM-compatible Personal Computer (PC). The 764 can generat[...]

Operating Basics 764 Digital Audio Monitor User Manual 35 The short report, shown in Figure 26, is a record of what happened during the session. It contains a print-out of the statistics tabulated on the 764 Session display , and lists several instrument settings that can affect meter behavior . In addition to all the information in the short repor[...]

Operating Basics 36 764 Digital Audio Monitor User Manual There are two types of time-stamped information, peak readings and error events. Peak readings are the highest true peak and the highest meter reading encountered during each consecutive peak reading interval in the session. An error event is a clip, mute, invalid sample, parity error , or c[...]

Operating Basics 764 Digital Audio Monitor User Manual 37 The Channel Status View The 764 Channel Status view displays the channel status information that is embedded in AES3-1992 (professional) or IEC-958 (consum- er) digital audio signals. Press CLEAR MENU (if necessary to exit a menu), then the VIEW :CH. ST A TUS button to select the Channel Sta[...]

Operating Basics 38 764 Digital Audio Monitor User Manual H In binary display mode (illustrated in Figure 29), you may turn the multi-function knob to highlight various bits or blocks of bits for same-screen “ plain English ” decoding. For example, bits 3 through 5 of byte 0 indicate the (pre)emphasis, if any , that has been applied to the audi[...]

Operating Basics 764 Digital Audio Monitor User Manual 39 The User Data View The 764 User Data view is intended to display optional user information that may be embedded in the “ user bits ” of digital audio signals. As this is written, the 764 can only interpret and display data that is block-aligned with the Channel status data; the 764 canno[...]

Operating Basics 40 764 Digital Audio Monitor User Manual Saving and Restoring Setups The 764 automatically stores current front panel and menu settings in non-volatile RAM. The instrument restarts every time in the Audio V iew/Session Display , with the session stopped and session time (if it is the current T ime Code selection) reset to zero. All[...]

Operating Basics 764 Digital Audio Monitor User Manual 41 been restored ”— will appear on screen to signal that the operation is complete. 4. Press CLEAR MENU to resume normal instrument operation with the newly-recalled settings. Figure 31: The Restore Setups submenu Editing a Setup T o edit an existing, saved setup: 1. Recall the Setup throug[...]

Operating Basics 42 764 Digital Audio Monitor User Manual[...]

764 Digital Audio Monitor User Manual 43 Reference This section contains detailed information about the more technical aspects of 764 operation. The subsections are: Level Meters , Corr elation Meter Algorithm , Selecting Headphone Channels , Submenus , and Using the RS-232 Port . Level Meters Also refer to The Level Meters Submenu beginning on pag[...]

Reference 44 764 Digital Audio Monitor User Manual always indicated by the peak segment, so actual headroom is always visible. W ith VU ballistics, the T est Level should correspond to the same level as above ( – 18 dBFS) if program exchange is important. In accordance with standard practice, the T est Level ( “ line – up level ” ) correspo[...]

Reference 764 Digital Audio Monitor User Manual 45 CODE ERR — A bi-phase coding violation (ERRor) has occurred in the digital data stream. All affected data samples are unreliable, and are therefore ignored. The instrument treats affected samples as “ zero samples ” for use by the meter bars and phase display . When Session is running, the in[...]

Reference 46 764 Digital Audio Monitor User Manual V BIT — Indicates that the V alidity bit is set high for one or more data samples. In the AES/EBU standard, a set validity bit indicates that the sample is not suitable for conversion to audio. By default, The meter bars and phase display treat the affected samples as a zero samples. When Session[...]

Reference 764 Digital Audio Monitor User Manual 47 and ( sig n ) + ( ) 1 ) if 4 fs ń 60 ȍ n + 0 ( L n R n ) is u 0 or ( sig n ) + ( – 1 ) if 4 fs ń 60 ȍ n + 0 ( L n R n ) is t 0 The actual correlation meter reading is the “ rolling average ” of the last i sample blocks: M + C 1 ) C 2 ) ,. .., ) C i i where i is determined by the Correlati[...]

Reference 48 764 Digital Audio Monitor User Manual Selecting Headphone Channels By factory default, the headphone output follows the phase display . That is, you can listen to the audio programs that are currently driving the Lissajous pattern and Correlation meter (refer to The Phase Display beginning on page 26). When you change the phase display[...]

Reference 764 Digital Audio Monitor User Manual 49 T able 2: Level Meters submenu Item Choices Factory setting Display Mode 4 Channels Ch 1–2 and Sum & Diff Ch 3–4 and Sum & Diff 4 Channels Interpolation OFF; ON ON Ballistics PPM T rue Peak Extended VU T rue Peak Peak Hold Time 0 to 10 seconds 2 Peak Program Level (dBFS) 0 to –30 dBFS[...]

Reference 50 764 Digital Audio Monitor User Manual or channels 3 – 4); the right-hand bars show (L+R)/2 (Sum) and (L – R)/2 (Diff) data derived from the two left-hand bars. The Sum and Difference bars use the same scale and ballistics, and all other settings, as the channel level meters. Interpolation. When interpolation is OFF , the 764 level [...]

Reference 764 Digital Audio Monitor User Manual 51 H Extended VU, a VU meter as defined in IEEE 152 – 1991, but with an extended dB-linear scale. The 764 meter bars will also contain true peak indicators when Extended VU is selected, and the display designation of this setting is “ vu + Peak. ” Note that this setting only affects meter perfor[...]

Reference 52 764 Digital Audio Monitor User Manual page 19) appears in a level meter , and it also af fects the number of clips detected during a Session and included in a session report (refer to The Session Display beginning on page 29). The range for this setting is 0 to 100; a setting of 0 turns mute detection Off, in which case no mutes will b[...]

Reference 764 Digital Audio Monitor User Manual 53 The De-emphasis Submenu The De-emphasis submenu, shown in T able 3, lets you select the appropriate de-emphasis for each of the four input channels. Enter the De-emphasis submenu from the TOP menu level by scrolling the highlight to the De-emphasis item and pressing a soft button. Then scroll the h[...]

Reference 54 764 Digital Audio Monitor User Manual Figure 34: The De-emphasis flags The Phase Display Submenu Use the Phase Displaly submenu (T able 4) to configure the appear- ance and behavior of the Audio V iew Phase display . T able 4: Phase Display submenu Item Choices Factory setting Format LISSAJOUS-SOUND- ST AGE LISSAJOUS-X – Y LISSAJOUS-[...]

Reference 764 Digital Audio Monitor User Manual 55 display orientation. Refer to page 26 for details on the phase display formats. Correlation Meter Speed. The Correlation Meter Speed setting determines how quickly the meter reacts to changes in phase relationship. The meter reading is actually an average of correlation over time, and this setting [...]

Reference 56 764 Digital Audio Monitor User Manual Headphones Submenu Use the Headphonse submenu (T able 5) to determine the input channels to be decoded and output through the headphone jack. T able 5: Headphones submenu Item Choices Factory setting Audio Source AUTO (follows phase); MANUAL AUTO (follows phase) Manual Left Channel 1; 2; 3; 4 1 Man[...]

Reference 764 Digital Audio Monitor User Manual 57 T able 7: Option 01 input submenu, audio inputs selected Item Choices Factory setting Audio Source Digital Audio Inputs Digital Video Input Digital Audio Inputs CH 1 – 2 input XLR-balanced BNC-unbalanced XLR-balanced CH 3 – 4 input XLR-balanced BNC-unbalanced XLR-balanced Reference input XLR-ba[...]

Reference 58 764 Digital Audio Monitor User Manual Serial Port Submenu The Serial Port submenu contains items used for setting the serial port parameters and controlling the content of the session report. The items and choices are listed in T able 10 and explained in the subsequent paragraphs. T able 10: Serial Port submenu items Item Choices Facto[...]

Reference 764 Digital Audio Monitor User Manual 59 Peak Reading Interval (sec). Use this item to choose the duration of the peak reading intervals. When a session is running, the 764 stores the time and value of the highest true peak and meter bar readings encountered during each interval. The time-stamped peaks are included in a long report; see F[...]

Reference 60 764 Digital Audio Monitor User Manual Restore Setups Submenu Restore a previously saved instrument configuration through the Restore Setups submenu (T able 12). The current instrument settings will be replaced by those in the saved Setup. T able 12: Restore Setups submenu Item Choices Factory setting Selection SETUP #1 SETUP #2 SETUP #[...]

Reference 764 Digital Audio Monitor User Manual 61 Service Submenu Use the Service submenu (T able 14) to select patterns for use in adjusting the display; find the version of software installed in the instrument and the instrument ’ s firmware identification number; and superimpose a numeric readout of signal levels on the Session display . Refe[...]

Reference 62 764 Digital Audio Monitor User Manual Using the RS-232 Port The primary use of the 764 RS-232 port is to output session reports. The reports can be sent directly to any ASCII printer with serial input, or captured on a PC and saved to disk. The RS-232 port also supports remote control of 764 Digital Audio Monitors with serial number B0[...]

Reference 764 Digital Audio Monitor User Manual 63 NOTE . RS-232 signals ar e named fr om the perspective of the DTE device. Since the 764 is a DCE device, pin 2 (Received Data) is an output fr om the instrument; that is, the data is r eceived by the connected DTE device. The 764 supports both hardware (R TS/CTS) and software (Xon/Xoff) handshaking[...]

Reference 64 764 Digital Audio Monitor User Manual Figure 36: Connecting to a DCE device with a DB25 serial port NOTE . Most Personal Computers ar e DTE devices; however , printers may be either DTE or DCE, and the type may not be obvious fr om the printer documentation or the gender of the RS-232 connector . If you have tr ouble outputting a 764 S[...]

Reference 764 Digital Audio Monitor User Manual 65 H Printer Communications Settings: ESP (automatic protocol sensing) 9600 (baud) 8 (bits) 1 (stop bit) DTR/DSR (flow control) H 764 Serial Port settings: Flow Control = HARDW ARE Baud Rate = 9600 Communicating with a PC. Y ou can use the software and settings below to establish communications with a[...]

Reference 66 764 Digital Audio Monitor User Manual Outputting a Session Report Y ou can test your RS-232 connection by outputting a short session report. 1. Confirm that the Copy selection of the 764 Serial Port submenu is set to either SHOR T REPOR T or LONG REPOR T . 2. Clear the on-screen menu and display the Audio Session view . 3. Run a sessio[...]

Reference 764 Digital Audio Monitor User Manual 67 The example command gets the time, gets the sample rate from the Channel 3 – Channel 4 input, and presses the V iew Audio button. When you abbreviate a command, you cannot leave out letters in the middle of a command argument. If the complete ar gument is needed to make a command unique, all the [...]

Reference 68 764 Digital Audio Monitor User Manual T able 16: General remote control commands (Cont.) Command Effect MSGON:<text> Displays a temporary message up to 58 charac- ters on the top line of the 764 display . Excess text does not wrap; it is truncated. MSGOFF Removes the temporary message. SYSTEM:ERROR Returns the last command error [...]

Reference 764 Digital Audio Monitor User Manual 69 T able 17: Remote control GET commands (Cont.) Command Retrieves V alue = selection GET :W ARFLAG:<0 – 3> 0=Meter bar #1 1=Meter bar #2 2=Meter bar #3 3=Meter bar #4 W arning flags GET :CURTP:<0 – 3> 0=Meter bar #1 1=Meter bar #2 2=Meter bar #3 3=Meter bar #4 Current true peak GET :[...]

Reference 70 764 Digital Audio Monitor User Manual PRESS Commands. Each front-panel button (except the power switch) has an equivalent PRESS:<button> command. Send the command to perform the same action as pressing the button. T able 18: Remote control PRESS commands Command Equivalent button PRESS:? Lists all the PRESS commands PRESS:APH PHA[...]

Reference 764 Digital Audio Monitor User Manual 71 MENU Commands. Use the MENU commands listed in T able 19 to make selections from the 764 on-screen menus. The menus need not be visible on the display to change a setting with a MENU command. SYNTAX: MENU:mnemonic:<number> (unrecognized number returns "Out Of Range Error") T able 19[...]

Reference 72 764 Digital Audio Monitor User Manual T able 19: Remote control MENU commands (Cont.) Command Submenu, item V alue = setting MENU:SYNCF:<0 – 1> 0=NO 1=YES Level Meters, Suppress Sync Loss Flags MENU:DEEMP1:<0 – 3> 0=None 1=Auto 2=CCITT J.17 3=50/15 De-emphasis, Channel 1 MENU:DEEMP2:<0 – 3> 0=None 1=Auto 2=CCITT[...]

Reference 764 Digital Audio Monitor User Manual 73 T able 19: Remote control MENU commands (Cont.) Command Submenu, item V alue = setting MENU:PBRIGHT :<0 – 3> 0=channel #1 1=channel #2 2=channel #3 3=channel #4 Phase Display , Pair B: Right Channel Assignment MENU:AUDSRC:<0 – 1> 0=Manual 1=Auto (follows phase) Headphones, Audio Sou[...]

Reference 74 764 Digital Audio Monitor User Manual T able 19: Remote control MENU commands (Cont.) Command Submenu, item V alue = setting MENU:BAUD:<0 – 3> 0=38400 1=19200 2=9600 3=2400 Serial Port, Baud Rate (Changing the Baud rate interrupts the remote connection) MENU:COPY :<0 – 2> 0=No Report 1=Short Report 2=Long Report Serial [...]

764 Digital Audio Monitor User Manual 75 Appendix A: Specifications T able 20: Digital audio inputs Characteristic Performance require- ments Supplemental information Impedance Balanced inputs (XLR) T erm switched in 11 0 Ω ± 5% 0.1 MHz to 6 MHz T erm switched out Return loss >30dB 0.1 MHz to 6 MHz. Relative to 11 0 Ω load at loop-through c[...]

Appendix A: Specifications 76 764 Digital Audio Monitor User Manual T able 21: Level Meters and Phase Display Characteristic Performance require- ments Supplemental information Attack and Decay Characteristics: Ballistics only: normal scale does not comply with standards. T rue Peak PPM decay characteristics No attack delay PPM per IEC 268-10A and [...]

Appendix A: Specifications 764 Digital Audio Monitor User Manual 77 T able 23: Interface parameter measurements (Cont.) Supplemental information Performance require- ments Characteristic Accuracy Within .01 kHz Synchronization Range Accuracy Indication ± 40% of dig. audio frame ± 2% of digital audio frame “ Frame Sync Err ” (session view) T a[...]

Appendix A: Specifications 78 764 Digital Audio Monitor User Manual T able 25: VGA output (Cont.) Characteristic Information Load Impedance Red Green Blue Horizontal Sync V ertical Sync 75 ohms 75 ohms 75 ohms TTL compatible TTL compatible Timing/Frequency Dot Clock Horizontal Rate V ertical Rate 25.175 MHz 31.469 kHz 59.940 Hz Pin Assignments pin:[...]

Appendix A: Specifications 764 Digital Audio Monitor User Manual 79 T able 26: Physical characteristics (Cont.) Information Characteristic Depth 17 inches (43.2 cm) Weight Net Shipping 10 lbs (4.54 kg) 17 lbs 5 oz (7.85 kg) T able 27: Power requirements Characteristic Information Input voltage 90 – 250 V AC Input frequency 50 or 60 Hz Current rat[...]

Appendix A: Specifications 80 764 Digital Audio Monitor User Manual T able 28: Environmental characteristics (Cont.) Characteristic Information T ransportation Meets the requirements of NTSB T est Procedure 1A, category II (24 inch drop) Equipment T ype Measurement Equipment Class Class I (grounded product) (As defined in IEC 1010-1, Annex H.) Inst[...]

Appendix A: Specifications 764 Digital Audio Monitor User Manual 81 T able 29: Certifications and compliances (Cont.) Australia/New Zealand Declaration of Conformity – EMC Complies with EMC provision of Radiocommunications Act per the following standard(s): AN/NZS 2064.1/2 Industrial, Scientific, and Medical Equipment: 1992 EC Declaration of Conf[...]

Appendix A: Specifications 82 764 Digital Audio Monitor User Manual[...]

764 Digital Audio Monitor User Manual 83 Appendix B: Error/W arning Messages This appendix lists and explains the various error and warning messages that can appear on the 764 display . Figure 32 on page 45 shows the In-bar message location. Channels not synchronized Location: Audio V iew , phase display . The left and right samples are not synchro[...]

Appendix B: Error/W arning Messages 84 764 Digital Audio Monitor User Manual CODE ERR Location: In-bar . (Code error .) A bi-phase coding violation has occurred in the digital data stream. All affected data samples are unreliable, and are therefore ignored. The instrument treats affected samples as “ zero samples ” for use by the meter bars and[...]

Appendix B: Error/W arning Messages 764 Digital Audio Monitor User Manual 85 INPUT UNLOCKED Location: In-bar . The 764 is not locked to an incoming signal on the indicated input channel. Data cannot be decoded; all data and all other errors are ignored. Likely causes of this message include: missing input signal; incorrect setting(s) in the Inputs [...]

Appendix B: Error/W arning Messages 86 764 Digital Audio Monitor User Manual MUTE Location: In-bar . The MUTE indicator flashes when the digital audio data on the input channel remains at zero-value for n or more consecutive samples. The factory default value of n is ten (10); it may be changed through the Level Meters submenu. A setting of zero (0[...]

Appendix B: Error/W arning Messages 764 Digital Audio Monitor User Manual 87 NOT PRESENT (Option 01 only) Location: In-bar . The NOT PRESENT flag indicates that, although video input is detected, there is no active audio on the corresponding channel (no channel ID is detected). P ARITY Location: In-bar . The incoming subframe does not have even par[...]

Appendix B: Error/W arning Messages 88 764 Digital Audio Monitor User Manual T o determine the exact cause of a SYNC ERR flag, select the 764 Session display and check the Sample Rate and Frame Sync Err fields in the SESSION ST A TISTICS panel. See The Session Display on page 29 for more information. The flag will persist until synchronization is a[...]

764 Digital Audio Monitor User Manual 89 Appendix C: Options This section describes the following options available with the 764 Digital Audio Monitor: H Option 01, Embedded Audio Input H Option 02, Analog Line Output (see page 93) H Power cord options (see page 99) Embedded Audio Input (Option 01) Option 01 provides the ability to monitor AES/EBU [...]

Appendix C: Options 90 764 Digital Audio Monitor User Manual T able 30: Option 01 characteristics (Cont.) Characteristic Description Equalization range Proper operation with up to 19.0 dB loss at 135 MHz using coaxial cable having 1/f 1/2 loss characteristics with a launch amplitude of 800 mV Return loss (input and output) w 15 dB relative to 75 oh[...]

Appendix C: Options 764 Digital Audio Monitor User Manual 91 5. T urn the multi-function knob to highlight the Channels menu item; then press the soft button that corresponds to the channel group (channels 1 – 4; 5 – 8; 9 – 12; or 13 – 16) that you want to monitor . If you do not know which audio channels are active on the input video, igno[...]

Appendix C: Options 92 764 Digital Audio Monitor User Manual above to select a group with active audio channels; then press CLEAR MENU to return to the audio view . Configure the Meters. Once you have selected the correct channel group, you can configure the level meter scale and offset by following the instructions under Configuring the Level Mete[...]

Appendix C: Options 764 Digital Audio Monitor User Manual 93 NOT PRESENT . The in-bar NOT PRESENT flag indicates that, although video input is detected, there is no active audio on the corresponding channel (no channel ID is detected). Analog Line Output (Option 02) Option 02 replaces the balanced XLR digital audio outputs with analog audio line ou[...]

Appendix C: Options 94 764 Digital Audio Monitor User Manual Option 02 instruments are set during manufacture for fixed output; refer to Configuring the Output on page 95 for information about changing the setting. When outputting to an unbalanced load (0 to 2.0 V RMS variable output only), you must connect one of the lines to ground; refer to Conn[...]

Appendix C: Options 764 Digital Audio Monitor User Manual 95 Configuring the Output Qualified service personnel can change the output configuration with the following procedure: CAUTION. The 764 contains static-sensitive components. The following pr ocedur e should be performed by qualified technicians only . 1. Disconnect power and all other conne[...]

Appendix C: Options 96 764 Digital Audio Monitor User Manual 3. Locate J913 and J914, the two rows of six connector pins on the AES circuit board assembly . The AES board is on the right side of the 764 when you view the instrument from the rear panel; J913 and J914 are near the end of the AES board that is closest to the front of the instrument. T[...]

Appendix C: Options 764 Digital Audio Monitor User Manual 97 Connecting the Instrument The appropriate method of connecting the Option 02 analog outputs to your system depends on the configured output level and the requirements of your particular installation. High-level, Balanced Output. When using high-level fixed or variable balanced output, con[...]

Appendix C: Options 98 764 Digital Audio Monitor User Manual Pin 3 ( – ) Pin 2 (+) Pin 1 (shield) Analog line output XLR (+) Gnd Receiving equipment unbalanced input Pin 3 ( – ) Pin 2 (+) Pin 1 (shield) (+) Gnd OR Figure 40: Connecting to an unbalanced input NOTE . Connecting a line to gr ound as shown in Figur e 40 for ces the analog outputs i[...]

Appendix C: Options 764 Digital Audio Monitor User Manual 99 Power Cords T able 33 lists and describes the available power cord options. Please contact your T ektronix representative if the power cord supplied with your instrument is not correct for the local power supply . T able 33: Power cord identification Plug configuration Normal usage Option[...]

Appendix C: Options 100 764 Digital Audio Monitor User Manual[...]

764 Digital Audio Monitor User Manual 101 Glossary CLIP One or more consecutive positive or negative full scale samples. The actual number of consecutive samples that constitute a CLIP may be adjusted through the Level Meters submenu; the factory setting is one (1). Copy Output a session report via the rear -panel RS-232 port. Frame Sync Err Frame [...]

Glossary 102 764 Digital Audio Monitor User Manual T est Level Also called “ alignment ” or “ reference ” level. Usually , the signal level used for system alignment. In the 764, this setting determines the placement of level meter markers and a meter bar intensity/color threshold.[...]

764 Digital Audio Monitor User Manual 103 Index A accessories, standard, 1 AGC, 28 alignment level, 43 See also test level Audio view , 13 B ballistics (meter), 43, 50 PPM, 43, 50 T rue Peak, 44, 50 VU, 44, 51 C cable, serial communications, 62 CCIR 645, 43 Channel Status view , 15, 37 CLEAR MENU button, 18 using, 12 CLIP flag, 22 CLIPs flag persis[...]

Index 104 764 Digital Audio Monitor User Manual Get commands, 68 H headphones, 7 selecting channels, 48 Headphones submenu, 48, 56 I IEEE 152-1991, 44 Ignore V alidity Bit, 52 Inputs digital audio, 3 configuring, 10 L TC, 5 reference, 5 RS-232, 6 SER. VIDEO (Option 01), 89 submenu, 56 VITC, 5 interpolation (oversampling), 50 K knob icon, 10 knobs B[...]

Index 764 Digital Audio Monitor User Manual 105 channel pairing, 16 format, 26, 54 submenu, 54 PPM (meter ballistics), 43 Press commands, 70 Product Support, xii R reference inputs, 5 reference level, 44 See also test level Remote command abbreviation, 66 command syntax, 66 control, 6, 62, 66 RESET Session soft button, 30 Restore Setups submenu, 40[...]

Index 106 764 Digital Audio Monitor User Manual U User Data view , 15, 39 V V alidity Bit, ignore, 52 VGA video output, 5 VIEW buttons, 16 V iews Audio, 13 Channel Status, 15 User Data, 15 VOLUME knob, 18 VU (meter ballistics), 44 W warning messages CODE ERR, 45, 84 Interpolation OFF , 50 LOW CONF , 45, 85 MUTE, 21 NO INPUT , 44, 85, 86 No V ideo I[...]