Audio Precision ATS-1 Access User Manual
  1. Manuals
  2. Brands
  3. Audio Precision Manuals
  4. Test Equipment
  5. ATS-1
  6. User manual

Audio Precision ATS-1 Access User Manual

Audio test system
Hide thumbs Also See for ATS-1 Access:
Table of Contents

Advertisement

Quick Links

Download this manual See also: User Manual
®
Advanced Test Equipment Rentals
www.atecorp.com 800-404-ATEC (2832)

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the ATS-1 Access and is the answer not in the manual?

Questions and answers

Related Manuals for Audio Precision ATS-1 Access

Summary of Contents for Audio Precision ATS-1 Access

  • Page 1 ® Advanced Test Equipment Rentals www.atecorp.com 800-404-ATEC (2832)
  • Page 2 ATS-1 Access User’s Manual Firmware Version 3.10 October 1998 Audio Precision Part No. 8211.0043...
  • Page 3 Copyright © 1998 Audio Precision, Inc. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the publisher.

  • Page 4: Table Of Contents

    Related documentation ......1-2 Introducing the ATS-1 Access ......1-2 Filter Shapes .
  • Page 5 Unbalanced Connections with the XLR Connector Panel ..3-33 Unbalanced Stereo Connections ..... . 3-35 ATS-1 Access User's Manual...
  • Page 6 Record-Reproduce Mode ......5-3 Compact Disc Players ....... 5-5 ATS-1 Access User's Manual...
  • Page 7 ........Index-1 ATS-1 Access User's Manual...

  • Page 8: Safety Symbols

    PROTECTIVE EARTH TERMINAL - This symbol marks a terminal that is bonded to conductive parts of the instrument. Confirm that this terminal is connected to an external protective earthing system. ATS-1 Access User's Manual...

  • Page 9: Safety Information

    INSTALLATION CATEGORY II, abbreviated “CAT II” on the instrument front panel. Do NOT substitute parts or make any modifications without the written approval of Audio Precision. Doing so may create safety hazards. This product contains lithium batteries. Dispose only in accordance with applicable regulations.

  • Page 10: Scope Of This Manual

    Scope of this manual This is the primary operator’s manual for the ATS-1 Access. It describes all aspects of the instrument’s features and functionality. For fundamental audio test and measurement information, we refer you to Audio Precision’s Audio Measurement Handbook, listed on the following page.

  • Page 11: Related Documentation

    Related documentation Description The ATS-1 Access can be operated via an IEEE-488 (GPIB) controller. Instructions are given in the ATS-1 GPIB Programmer’s Reference Guide, listed below. Related documentation ATS-1 GPIB Programmer’s Reference Guide AP Part No. 8211.0045 Audio Measurement Handbook AP Part No.
  • Page 12 4-46. printout of bargraph displays. The ATS-1 Access is capable of generating low-distortion sine and square waveforms, plus an intermodulation distortion test signal (when the intermodulation distortion option is installed). Figure 1-1.
  • Page 13 Introducing the ATS-1 Access Description Measurements may be displayed in a wide variety of units, including the following: volts dBm (with a user-specified impedance reference) dBr (dB relative to a stored measured value) dBg (dB relative to the present generator output amplitude)
  • Page 14 Reference Manual for complete documentation on controlling the ATS-1 via IEEE-488. The ATS-1 Access can be purchased with or without the IMD option, which allows generation and analysis of intermodulation distortion. The IMD measurement function conforms to the SMPTE and DIN testing standards, and is described on page 4-27.

  • Page 15: Filter Shapes

    Filter Shapes Description Filter Shapes This section shows the shapes of the filters built into the ATS-1 Access. A number of other filter shapes are available as option filters. 100k 200k Figure 1-2. Shapes of Bandwidth-limiting filters: 22 Hz Highpass,...
  • Page 16 Filter Shapes CCIR-468-4 DOLBY Figure 1-3. Shape of CCIR filter. CCIR-468-4 has the 0 dB point at 1 kHz, while the Dolby curve has the 0 dB point at 2 kHz. Figure 1-4. Shape of A-weighting filter ATS-1 Access User's Manual...

  • Page 17: Identification Of Features And Options

    1-9). If not present, the front-panel IMD button will have no effect. Connector Panel Options The connector panel normally shipped with the ATS-1 Access has BNC connectors and banana jacks for the generator outputs and analyzer inputs and is mounted on the front. This is the configuration shown in the figures in this manual.

  • Page 18: Options Label

    Options Label The Options Label (see Figure 1-5) specifies any options that are installed in your ATS-1 Access. It is located on the lower center of the rear panel. The options label is filled out by the manufacturing technician when configuring the instrument for the customer.

  • Page 19: Block Diagrams

    Overall Block Diagram Figure 1-6 is a simplified block diagram of the ATS-1 Access. The generator consists of a sinewave and squarewave generator transformer-coupled to the output connectors. When the IMD option is present, a second sinewave oscillator is added.
  • Page 20 OUTPUT SOURCE IMPEDANCE CHANNEL SIGNAL SUMMATION BACK OUTPUT TERMINATION ATTENUATOR GENERATOR MAIN OUTPUTS OSCILLATOR BALANCING TRANSFORMER OUTPUT SQUARE SOURCE AMPLIFIER WAVE IMPEDANCE GENERATOR CHANNEL BACK TERMINATION Figure 1-6. Overall block diagram of the ATS-1 Access ATS-1 Access User's Manual 1-11...

  • Page 21: Generator Output Circuit

    Pin 2 of the generator XLR connectors is hot in unbalanced mode, working against Pin 3 low. An additional 25 Ω source resistance is switched in series with the high terminal in unbalanced mode to preserve the same source impedance as in balanced mode. 1-12 ATS-1 Access User's Manual...
  • Page 22 Source On/Off Impedance Output A 25 Ω 50 Ω Circuit comon 15 nF typical To Analyzer GEN A MON Chassis Output B 50 Ω To Analyzer GEN B MON Figure 1-7. Simplified generator output circuit ATS-1 Access User's Manual 1-13...

  • Page 23: Analyzer Input Circuit

    30 V rms will cause the termination to disconnect to prevent damaging the termination. µ µ Input Attenuator 600 Ω 600 Ω To Analyzer µ µ Figure 1-8. Simplified analyzer input circuit 1-14 ATS-1 Access User's Manual...
  • Page 24 Description Analyzer Input Circuit ATS-1 Access User's Manual 1-15...

  • Page 25: Getting Started

    Appendix A for changing the line voltage selection. After verifying or correcting the line voltage selection, connect the line cord from the power outlet to the power cord connector and move the front-panel Power switch to the ‘On’ position (marked ‘1’). ATS-1 Access User's Manual...

  • Page 26: Rackmounting

    Rackmounting Getting Started Rackmounting The ATS-1 Access may be rackmounted, either via fixed brackets or with slide-out tracks. Refer to Appendix B for parts required and procedures. Concepts and Terminology Analog vs. Digital Note: The ATS-1 Access tests analog devices only.

  • Page 27: Balanced Vs. Unbalanced

    The most common balanced connector is the XLR connector. XLR For input and connections are almost always balanced, although sometimes the XLR output cable connector can be used in balanced or unbalanced configurations. considerations, see page 3-30. ATS-1 Access User's Manual...

  • Page 28: Self Test

    Self Test Getting Started Self Test The ATS-1 Access has the capability of performing a functional self test. This can be run periodically to make certain that your instrument is operating properly. Before running the self test, let the instrument warm up for at least an hour.
  • Page 29 This runs very much the same as a normal self test except that if an error is encountered, it will not wait for you to press a key before continuing. Following is a sample printer output from a self test. ATS-1 Access User's Manual...
  • Page 30 Self Test Getting Started Audio Precision ATS-1 Access Self Test Version 3.10 Test Number and Description, Low Limit,Measured, High Limit, P/F TEST 1.0 100 Hz FREQUENCY 99.500 Hz 99.939 Hz 100.50 Hz PASS TEST 1.1 1 kHz FREQUENCY 995.00 Hz 999.57 Hz 1.0050kHz PASS TEST 1.2...
  • Page 31 20 Hz PHASE -2.0 PASS TEST 8.1 1 kHz PHASE -2.0 PASS TEST 8.2 20 kHz PHASE -2.0 deg -0.2 PASS TEST 9.0 WOW AND FLUTTER 0.950 % 1.003 % 1.050 % PASS Passed Self Test ATS-1 Access User's Manual...
  • Page 32 Self Test Getting Started ATS-1 Access User's Manual...

  • Page 33: Operational Overview

    Operational Overview Front Panel Controls and Connectors The ATS-1 Access front panel controls are grouped as shown in Figure 3-1. Each group is summarized in the following subsections. GPIB STATUS dBr ZERO FUNCTION FREQUENCY POWER SOFT KEYS INDICATORS DISPLAY KEYS...

  • Page 34: Frequency Controls

    AMPLITUDE controls adjust the top and bottom amplitude values of the sweep. The +10 dB and 10 dB keys will cause the selected AMPLITUDE parameter to increase or decrease by a factor of 10 dB. ATS-1 Access User's Manual...

  • Page 35: Input Keys

    Input keys, see page connectors or from an internal path directly from the generator. 3-16. OUTPUT Keys The OUTPUT keys are used to turn each generator channel On and Off. ATS-1 Access User's Manual...

  • Page 36: Instrument Mode Keys

    Pressing any key will turn it on again (but will not execute that keys function). ATS-1 Access User's Manual...

  • Page 37: Dbr Zero Key

    To invert the display so that the background is dark and the characters are light, refer to the Setup Panel section, page 3-10. ATS-1 Access User's Manual...

  • Page 38: Monitor Operation

    Front Panel Controls and Connectors Operational Overview MONITOR Operation The ATS-1 Access has a built-in monitor for audible monitoring of signals, either with stereo headphones or through a built-in speaker that receives the combined A and B channels. To use stereo headphones, plug them into the MONITOR jack. To use monophonic headphones, a special stereo-to-mono headphone adapter must be used.
  • Page 39 SWEEP PANEL GEN ONLY PANEL Shortcut: Pressing any FUNCTION ANLR ONLY PANEL button will take you to the Main Panel, even if the measurement function does not change. SETUP PANEL GPIB PANEL Figure 3-3. Navigating the panels ATS-1 Access User's Manual...
  • Page 40 This panel has up to three real-time readings at the top like the Main panel. The generator and soft key areas have been replaced with a horizontal bargraph. This bargraph shows a real-time analog-like display of a selected reading. See page 4-40 for more discussion of the Bargraph panel. ATS-1 Access User's Manual...
  • Page 41 If any panel besides the Sweep Panel is displayed, pressing PRINT will result in an immediate printout of the data on the display. The type of printout will depend on which panel is currently displayed. For more information on printing and the Print panel, see page 4-46. ATS-1 Access User's Manual...

  • Page 42: Setup Panel

    The clock will restart as soon as the soft key is pressed with the seconds highlighted. The lower center soft key controls the display inversion. Inverting the display causes the letters to appear white, with a blue background, instead of blue against a white background. 3-10 ATS-1 Access User's Manual...

  • Page 43: Screen Saver

    If one key is released before the other, the display will relight, but eight hour mode will still be invoked. Turning power off and back on will return the unit to the normal two hour screen saver. ATS-1 Access User's Manual 3-11...

  • Page 44: Controlling The Generator

    Controlling the Generator Generator Overview The ATS-1 Access generator can generate sine waves from 10 Hz to 120 kHz, with amplitudes from zero up to around 26 Vrms Balanced or 13 Vrms Unbalanced. It can also generate square waves from 20 Hz to 30 kHz with amplitudes from zero to around 34.4 Vpp Balanced...
  • Page 45 Subsequent presses of the bottom center soft key permit selection between 50 Ω Unbalanced, 50 Ω Balanced, 150 Ω Balanced, and 600 Ω Balanced configurations. The upper center soft key allows control of the units for analog generator amplitude. ATS-1 Access User's Manual 3-13...

  • Page 46: Generator Loading

    When you are using the dBm unit for generator output, the generator will be set to a voltage that would cause the specified power (in dBm) to be dissipated in a load of 3-14 ATS-1 Access User's Manual...

  • Page 47: Controlling The Analyzer

    Controlling the Analyzer Analyzer Overview The ATS-1 Access analyzer is generally configured for only one type of measurement at a time. The type of measurement currently being displayed is determined by the current measurement function. Often a single measurement function will provide measurement of several related parameters.

  • Page 48: Input Selection Keys

    Some FUNCTION buttons choose two different measurement functions. The first measurement is selected by the first press on the FUNCTION button, and the second is selected with a second press. 3-16 ATS-1 Access User's Manual...

  • Page 49: Units

    Operational Overview Units Units The ATS-1 Access supports a full set of industry-standard units. The following table provides a quick reference to units; the following text gives units details. Unit Type Description Amplitude/ Relative percentage of two measurements Frequency ∆%...
  • Page 50 The decibel reading is calculated from the measured amplitude using the following formula: DB = 20 log V where V is the measured amplitude and Vr is the reference amplitude. 3-18 ATS-1 Access User's Manual...
  • Page 51 The X/Y unit is available only in Ratio mode. The reading is a raw result of dividing one amplitude reading by another. This is usually used for gain or attenuation through a device. ATS-1 Access User's Manual 3-19...

  • Page 52: Is It Dbm Or Dbu

    In fact, it is defined as the voltage in decibels relative to 0.7764 volts, which is the voltage across a 600 Ω resistor dissipating one milliwatt. 3-20 ATS-1 Access User's Manual...

  • Page 53: Power Units

    600 Ω equipment, you can use dBm units. You can easily 4-38. measure the input impedance of a device using the ATS-1 Access’s Gen Load function. If you are testing equipment terminated in high impedances, or if you...

  • Page 54: Time And Frequency Units

    3 kHz or 3.15 kHz intended frequency using the following formula: % = abs where D is the frequency deviation and F is the intended frequency. 3-22 ATS-1 Access User's Manual...

  • Page 55: Phase Units

    0 degrees means the two signals are in phase, 180 degrees means they are out of phase, and by 360 degrees they are back in phase. However, the scale may be shifted to span any 360-degree area, generally between -360 degrees and +360 degrees. ATS-1 Access User's Manual 3-23...

  • Page 56: Generator Output And Analyzer Input Connectors

    . field. The alternative styles include: XLR and banana jack connectors; WE-310 tip-ring-sleeve and banana jack connectors; 1/4-inch phone and banana jack connectors. 3-24 ATS-1 Access User's Manual...

  • Page 57: Rear Panel Connectors

    You will notice provision for additional connectors that are not installed. This is because the rear panel is common to both the ATS-1 Access and ATS-1 Dual Domain instruments, in order to facilitate the upgrade path. DIGITAL...

  • Page 58: Monitor Outputs

    Printer Connector The ATS-1 Access is equipped with a parallel printer port for connection to a printer. The printer can then be used to print hi-resolution graphs or numerical data from a sweep, and any screen data may be captured and printed.

  • Page 59: Gpib Interface

    The computer must be equipped with appropriate GPIB controller hardware (available on a plug-in card) and GPIB control software. Connection from the host computer to the ATS-1 Access requires a standard GPIB cable. These same cables may also be used to connect to other devices in a GPIB chain.

  • Page 60: External Connections

    Electrical connections between a device under test and the test instrument are typically made with test cables. Analog test cables for the ATS-1 Access should have appropriate connectors on both ends for connection to the test instrument. Adapters may be used to adapt a standard cable to the device or test instrument.
  • Page 61 The 150 Ω and 600 Ω selections are generally only used with devices that have an equivalent input impedance. Check the input specifications for your device. For devices with higher input impedances, choose 50 Ω. ATS-1 Access User's Manual 3-29...

  • Page 62: Input And Output Cables

    Input and Output Cables Operational Overview Input and Output Cables Connecting the ATS-1 Access to a device under test may require construction of special cables. This section describes proper wiring of cable connections and gives examples of cables for common connector applications.
  • Page 63 The same situation exists for the input to the analyzer: the input to each channel is balanced, and the BNC connector shell is floating. You can ground the shell in the manner described above if desired. ATS-1 Access User's Manual 3-31...
  • Page 64 Balanced connections with the XLR connector panel are almost always made with standard XLR-to-XLR cables. These cables may be purchased from Audio Precision and are available from many other sources. Figure 3-17 shows proper electrical connections for balanced connectors. The generator should be configured for a balanced output (either 50 Ω...

  • Page 65: Unbalanced Connections With The Xlr Connector Panel

    2 Conductor shielded cable 1/4" Phone Plug or Female Sleeve Shield not connected this end XLR Male 2 Conductor shielded cable BNC Connector or Female Shield not connected this end Figure 3-17. Preferred unbalanced cable connections ATS-1 Access User's Manual 3-33...
  • Page 66 XLR Male RCA/Phono Plug or Female Single Conductor shielded cable XLR Male 1/4" Phone Plug or Female Sleeve Single Conductor shielded cable XLR Male BNC Connector or Female Figure 3-18. Unbalanced connections using single-conductor cable 3-34 ATS-1 Access User's Manual...

  • Page 67: Unbalanced Stereo Connections

    Female 2 Conductor shielded cable Stereo Left Plug Channel Sleeve Ring Right Channel XLR Male Single conductor shielded cable or Female Left Channel Stereo Plug Sleeve Ring Right Channel Figure 3-19. Stereo unbalanced cable connections ATS-1 Access User's Manual 3-35...
  • Page 68 Input and Output Cables Operational Overview 3-36 ATS-1 Access User's Manual...
  • Page 69 SPEAKER/ JUMPER HEADPHONE INPUT TERMINATION READING MONITOR BAND PASS FILTER PRIMARY READING DETECTOR INPUT BANDWIDTH RANGING WEIGHTING LIMITING FILTERS FILTERS CHANNEL B INPUT TERMINATION FREQUENCY COUNTER LCD DISPLAY Figure 4-2. Block Diagram of Analog AMPL Measurement ATS-1 Access User's Manual...

  • Page 70: Function Descriptions

    FREQUENCY controls. The SELECTIVE filter can be used to create spectrum-analysis sweeps. In this type of measurement, a narrow bandpass is swept across a range of frequencies, taking an amplitude measurement at each step. ATS-1 Access User's Manual...
  • Page 71 AUX1 and no filter is selected. AUX2 – Weighted with optional weighting filter installed in slot 2. If there is no filter in slot 2, the display will read NO AUX2 and no filter is selected. ATS-1 Access User's Manual...

  • Page 72: Noise

    If this unit is selected, a special signal-to-noise ratio mode is invoked. This mode turns the generator on and off at regular intervals, making a level measurement in each state. The displayed result is the difference in dB between the ATS-1 Access User's Manual...

  • Page 73: Level

    INTERNAL SPEAKER/ JUMPER HEADPHONE CHANNEL A READING MONITOR INPUT PRIMARY TERMINATION READING DETECTOR INPUT RANGING SECONDARY READING DETECTOR CHANNEL B INPUT RANGING LCD DISPLAY FREQUENCY COUNTER INPUT TERMINATION Figure 4-6. Block Diagram of Analog LEVEL Measurement ATS-1 Access User's Manual...
  • Page 74 B. The Level function provides the best amplitude accuracy of which the ATS-1 Access is capable, as long as the measured signal is above about 10 mV. The Amplitude function provides wider dynamic range, but at reduced accuracy.

  • Page 75: Thd+N (Total Harmonic Distortion Plus Noise)

    READING MONITOR INPUT TERMINATION BANDWIDTH NOTCH LIMITING FILTER PRIMARY FILTERS READING DETECTOR INPUT RANGING WEIGHTING FILTERS CHANNEL B INPUT AVERAGING TERMINATION FREQUENCY COUNTER SECONDARY READING LCD DISPLAY DETECTOR Figure 4-8. Block Diagram of Analog THD+N Measurement ATS-1 Access User's Manual...
  • Page 76 (20 Hz - 22 kHz) and greater than about 20 mV outside the audio band. If the signal amplitude is too low, tuning operation will cease and the display will read Low. The THD must also be less than about 10% THD+N. ATS-1 Access User's Manual...
  • Page 77 This is used to reduce digit bobble, especially when testing distortion in the presence of noise and flutter from analog tape recorders. ATS-1 Access User's Manual...
  • Page 78 THD+N reading will be higher. In addition, the voltmeter used to measure the signal before filtering has limited dynamic range, so accuracy suffers when measuring signals with a fundamental tone below about 10 mV. 4-10 ATS-1 Access User's Manual...

  • Page 79: Understanding Thd+N

    Crosstalk is a certain type of interference caused by sound leaking in from other audio channels within the device. The THD+N measurement includes all four types of unwanted sound. If any of these are excessive, it will be noticeable in a THD+N reading. ATS-1 Access User's Manual 4-11...
  • Page 80 The signal is then run through a narrow bandreject filter to eliminate the fundamental tone. The spectrum then looks like this: Fundamental Tone Greatly Reduced -100 -120 -140 Figure 4-10. THD + N spectrum with fundamental filtered 4-12 ATS-1 Access User's Manual...

  • Page 81: Surprises And Pitfalls In Thd+N Measurements

    Often THD+N tests will be used in conjunction with noise-only tests to be certain that a problem is not hiding underneath a more significant contributor. The section Isolating Sources of THD+N (page 4-37) explains some strategies for determining which unwanted signal is dominating the reading. ATS-1 Access User's Manual 4-13...

  • Page 82: Selecting Bandwidth

    400 Hz. Following is an example of the use of various bandwidth-limiting filters. The spectrum of the original signal may look like this: -100 -120 -140 100k 200k 300k 4-14 ATS-1 Access User's Manual...
  • Page 83 100k 200k 300k Figure 4-12. Spectrum with 400 Hz bandpass filter applied The THD+N now measures 0.185 %. From this, we can determine that the hum product was contributing 0.044 % to the THD+N reading. ATS-1 Access User's Manual 4-15...
  • Page 84 400 Hz and a high band limit of 300 kHz. The spectrum -100 -120 -140 100k 200k 300k Figure 4-14. Device with HF noise, 1 kHz fundamental filtered is shown after the bandreject filtering, which has removed the 1 kHz fundamental. 4-16 ATS-1 Access User's Manual...

  • Page 85: Changes With Frequency

    THD + N with interfering signal at same frequency as fundamental using a fundamental at 50 or 60 Hz in the presence of significant hum. For example, you may see a THD+N sweep that looks like this: ATS-1 Access User's Manual 4-17...

  • Page 86: Changes With Amplitude

    Therefore, as the amplitude of the fundamental tone decreases there will be an apparent increase in the calculated ratio. 4-18 ATS-1 Access User's Manual...

  • Page 87: Thd+N At 100% (Or 0 Db)

    If the THD+N reads 100% (or 0 dB), the amplitude of signal is the same before and after the filter. Even if a device is creating a huge amount of distortion or interference, the THD+N should be less than ATS-1 Access User's Manual 4-19...

  • Page 88: Isolating Sources Of Thd+N

    This will reconfigure the instrument to read only the filtered amplitude. Check the THD+N reading and then turn off the generator. If the reading changes significantly, then a significant amount of distortion is contributing to the reading. 4-20 ATS-1 Access User's Manual...
  • Page 89 Wherever there is a significant interference source (including hum), you will see a peak in the graph. If the signal is dominated by random noise, it will be essentially smooth. ATS-1 Access User's Manual 4-21...

  • Page 90: Sinad

    MONITOR INPUT TERMINATION BANDWIDTH NOTCH LIMITING FILTER PRIMARY FILTERS READING DETECTOR INPUT RANGING WEIGHTING FILTERS CHANNEL B INPUT AVERAGING TERMINATION FREQUENCY COUNTER SECONDARY READING LCD DISPLAY DETECTOR Figure 4-20. Block Diagram of Analog SINAD measurement 4-22 ATS-1 Access User's Manual...
  • Page 91 400 Hz and 1 kHz. Changing this setting changes both the generator and the notch filter to the selected frequency. The generator frequency may then be changed using the FREQUENCY controls, but the notch will remain parked, so the reading will be invalid. ATS-1 Access User's Manual 4-23...
  • Page 92 RMS detector in accordance with CCIR-468. The 22 Hz lower limit is only available if the upper limit is 22 kHz; the <10 Hz lower limit is only available with other upper limits. 4-24 ATS-1 Access User's Manual...

  • Page 93: Phase

    Function Descriptions Phase Phase The Phase function is selected by pressing the FUNCTION PHASE key. The Phase mode measures the difference in phase (or time shift) between two sine or square waves. Both channels must have the same frequency; phase measurements between two signals of different frequencies are meaningless (and the reading will wander continuously).
  • Page 94 Phase Function Descriptions For more The center of the display shows the amplitude of the selected channel. information on Pressing the upper center soft key will select among the available units. amplitude units, ee The usual absolute and relative amplitude units are available. page 3-17.

  • Page 95: Imd

    The IMD measurement function is selected by pressing the FUNCTION IMD button. It is only available if the Intermodulation Distortion Option is installed. The ATS-1 Access can be purchased with or without this option, or the option can be added at a later time.
  • Page 96 Function Descriptions INPUT MONITOR GENERATOR MONITORS INTERNAL CHANNEL A SPEAKER/ JUMPER HEADPHONE READING INPUT PRIMARY MONITOR TERMINATION READING DEMODULATOR/ FILTER DETECTOR INPUT RANGING SECONDARY READING LCD DISPLAY DETECTOR CHANNEL B INPUT TERMINATION Figure 4-24. Block diagram of the IMD measurement When exiting the IMD measurement function, the generator waveform is changed back to sine.

  • Page 97: Ratio

    Function Descriptions Ratio Frequency sweeps are not available in IMD mode since the standards define a fixed set of frequencies. Amplitude sweeps are supported. Although the SMPTE standard calls for a signal with a 60 Hz lower tone and a 7 kHz upper tone, experience suggests that the lower tone should not be a multiple of the line frequency, which in many areas is 60 Hz.
  • Page 98 Ratio Function Descriptions INPUT GENERATOR MONITOR MONITORS INTERNAL CHANNEL A SPEAKER/ JUMPER HEADPHONE READING INPUT PRIMARY MONITOR TERMINATION READING DETECTOR INPUT RANGING RATIO (X/Y) PROCESSING LCD DISPLAY SECONDARY READING DETECTOR CHANNEL B INPUT RANGING INPUT TERMINATION FREQUENCY COUNTER Figure 4-27. Block diagram of analog RATIO measurement Pressing INPUT A or INPUT B will select the chosen channel for measurement, with the other input channel as the reference.
  • Page 99 Function Descriptions Ratio The following table shows proper Mode choices: Measurement Ratio Numerator Denominator Mode Attenuation, Ch. A A Input, <8mV Generator A, >8mV Gain, Ch. A A Input, >8mV Generator A, <8mV Attenuation, Ch. B B Input, <8mV Generator B, >8mV Gain, Ch.

  • Page 100: W+F (Wow And Flutter)

    The reference tone is usually pre-recorded on a device with minimal wow and flutter. The output is then sent to the ATS-1 Access for analysis. The instrument determines the amount of speed fluctuation and the amount of speed error.

  • Page 101: W+F (Wow And Flutter)

    Function Descriptions W+F (Wow and Flutter) frequency is above 3.35 kHz, the display will read Hi Fr (high frequency). No valid W+F readings can be obtained outside of this frequency range. The upper center section of the display shows the level (amplitude) of the incoming signal.

  • Page 102: Xtalk (Crosstalk)

    XTALK (Crosstalk) Function Descriptions Wow and flutter of 3-head tape machines should not be measured during simultaneous record-reproduce mode, since this will result in spectral nulls which can give erroneously low readings. XTALK (Crosstalk) The XTALK measurement function is selected by pressing the FUNCTION XTALK key.
  • Page 103 Function Descriptions XTALK (Crosstalk) In Crosstalk measurement function, the selected channel is always the non-driven channel, and it is from this channel that the main measurement is taken. The alternate channel is the driven channel, and its amplitude is measured for comparison to the non-driven channel.

  • Page 104: Ac Mains (Power Line Monitor)

    AC Mains (Power Line Monitor) Function Descriptions AC Mains (Power Line Monitor) The AC Mains measurement function is selected by pressing the FUNCTION AC MAINS key. The AC Mains mode monitors the power supply line to the ATS-1 Access. Figure 4-33. Main panel in AC MAINS function INPUT MONITOR...
  • Page 105 Function Descriptions AC Mains (Power Line Monitor) The upper right section of the display shows the measured frequency of the supply line. The only available units are Hz. The upper right soft key can be used to turn the measurement off. The sweep function is not available in AC Mains measurement function.

  • Page 106: Gen Load

    Gen Load Function Descriptions Gen Load The Gen Load (Device Input Impedance) measurement function is available by pressing the FUNCTION GEN LOAD key. The Gen Load function is used to measure the input impedance of a device under test. It does this by generating a signal through the internal 600 Ω...
  • Page 107 Function Descriptions Gen Load measured frequency of the signal. The only available unit is Hz, but the upper right soft key can be used to turn the reading off. Because of the nature of the calculation, only one channel can be used at a time.

  • Page 108: Bargraphs

    Bargraphs Function Descriptions Bargraphs The Bargraph Panel is selected by pressing the INSTRUMENT MODE BARGRAPH key. On the Bargraph Panel, the generator and lower soft key sections of the display are replaced with a horizontal bargraph. The bargraph shows the primary measurement in an analog-type display, with indicators for the minimum and maximum values.
  • Page 109 (using the same soft key). When you return to the Bargraph Panel, the bargraph units will be the same as they were before, but the numerical display will show the newly selected units. The ATS-1 Access remembers separate units for each numerical display and the bargraph for each measurement function.

  • Page 110: Sweeps

    Sweeps Function Descriptions Sweeps The Sweep Panel is selected by pressing the INSTRUMENT MODE SWEEP button. The Sweep Panel is used to create graphs of a measurement vs. frequency or amplitude. The frequency or amplitude is stepped through a number of points (or swept) across a user-defined range, taking one measurement at each point.
  • Page 111 Sweeps of LEVEL do not have the 150 step choice due to memory limitations. External sweeps are a special type of sweep in which the ATS-1 Access generator does not perform the stimulus changes they come directly from the device under test, usually from a test tape or CD.
  • Page 112 MEDIUM sweep speed inserts a time delay of approximately 0.9 sec after changing the generator setting, before the analyzer begins taking data. Its principal intent is for use on a ATS-1 Access generator feeding an audio transmission link while the analyzer section of another Portable makes EXTERNAL sweep measurements at the receiving end.

  • Page 113: Starting The Sweep

    Function Descriptions Sweeps Starting the Sweep When you have made all the necessary settings, press INSTRUMENT MODE SWEEP again to start the sweep. You will see the upper right section of the display change to a graph and you will see points being plotted as the data is taken.

  • Page 114: External Sweeps

    Printing Function Descriptions External Sweeps External sweeps are a special type of sweep in which the ATS-1 Access generator does not perform the stimulus changes they come directly from the device-under-test, usually from a test tape, test CD, or remotely located sweep source.
  • Page 115 Function Descriptions Printing ® The IBM GRAPH setting supports Epson and Epson-compatible ink ® jet printers, Canon ink jet printers, and common dot-matrix printers. ® The PCL GRAPH setting supports all Hewlett-Packard ink jet and laser printers, and most other laser printers. Some laser printers will require you to select a Hewlett-Packard compatible mode on the printer.
  • Page 116 Printing Function Descriptions If you press the PRINT button within the Sweep Panel, the display will change to look something like this: Figure 4-41. Print panel This panel allows you to print the sweep data four different ways: Pressing the lower left soft key will print a high-resolution graph of the sweep data.
  • Page 117 No matter what PRINT mode is chosen, the display colors will invert while the ATS-1 Access is sending the data to the printer. When the display returns to its normal color scheme, all the data has been sent to the printer, so you may proceed to the next test.
  • Page 118 Printing Function Descriptions A print of the high-resolution graph usually takes about 30 to 45 seconds, depending on the type of printer. A screen dump usually takes about 10 seconds, and a table printout is even faster, depending on the number of points in the sweep. The self test does not use the PRINT key for printing the test results.

  • Page 119: Saving And Recalling Setups

    Saving and Recalling Setups Saving and Recalling Setups The ATS-1 Access has the facility of storing thirty different test setups in memory. Each of these setups stores all the settings necessary to repeat a measurement exactly, so that a commonly-run test can be stored and recalled with only a few keypresses.

  • Page 120: Saving And Recalling Setups

    Saving and Recalling Setups Function Descriptions the write-protection. If the setup has already been deleted, the upper left soft key will change to undelete the setup, restoring it to the menu. To recall a saved setup, use the PAGE and SCROLL keys to highlight the setup to recall and then press RECALL.

  • Page 121: Printing Saved Data

    Function Descriptions Printing Saved Data Upper and lower case letters are available, as well as numbers and a few special-purpose symbols. The following characters are available, in the order in which they are shown: Figure 4-47. Character set When you have set the name as desired, press the upper center soft key (SAVE) to save the setup.
  • Page 122 Printing Saved Data Function Descriptions 4-54 ATS-1Access User's Manual...

  • Page 123: Applications

    At the “receive” end, choose the measurement function desired. Select SWEEP mode and EXTERNAL sweep function. Press SWEEP and the analyzer should start acquiring and plotting data from the continuously-stepping generator at the other end of the link. ATS-1 Access User's Manual...

  • Page 124: Analog Tape Recorder Alignment And Performance Verification

    EXTERNAL mode in SWEEP mode. EXTERNAL mode will follow an increasing-frequency or decreasing-frequency sequence of tones on the reference tape while ignoring any voice announcements between tones. If dBr units are used, the mid-frequency (usually 1 kHz) ATS-1 Access User's Manual...

  • Page 125: Record-Reproduce Mode

    Thus, a flat phase-vs-frequency graph from 1 kHz to high frequencies indicates proper alignment with no chance of accidentally aligning for a complete rotation at 15 kHz. ATS-1 Access User's Manual...
  • Page 126 (30 step is typical) across the entire audio band. The resulting graph may be printed for permanent documentation of recorder performance. For k3 (third harmonic) distortion measurements such as when measuring MOL (maximum output level), install an optional bandpass ATS-1 Access User's Manual...

  • Page 127: Compact Disc Players

    The 22 Hz-22 kHz bandpass filters should be used in this application. Each channel of the CD player must be tested separately, since THD+N function measures only one channel at a time. ATS-1 Access User's Manual...
  • Page 128 Applications Compact Disc Players ATS-1 Access User's Manual...

  • Page 129: Appendix A - Changing Mains Voltage Selection

    Appendix A - Changing Mains Voltage Selection The ATS-1 Access is configured at the factory for the line voltage at its intended destination, so usually the voltage will be correct unless the unit has been transported into another area. This appendix describes the procedure for changing the voltage setting, which may be necessary under some circumstances.

  • Page 130: Changing The Line Voltage Selection

    The voltage selector card and indicator pin should now be in one of the positions shown on the following figure. ATS-1 Access User's Manual...

  • Page 131: Checking The Fuse Block Orientation

    If the fuse block is in the correct orientation for the selected voltage, skip forward to the section on Checking the Fuses (page A-5). If not, continue with the next section, ‘Changing the Fuse Block Orientation.’ ATS-1 Access User's Manual...

  • Page 132: Changing The Fuse Block Orientation

    Fuse Block fits around the top section of the Screw Pedestal. The Fuse Block should sit flat, parallel to the Cover. Tighten the screw. Figure A-5 shows the two fuse block orientations. 4. Check the fuses as instructed in the next section. ATS-1 Access User's Manual...

  • Page 133: Checking The Fuses

    4. Replace fuses if necessary. Replace Cover, making sure that indicator tip is inserted in correct indicator hole for the selected line voltage (see Figure A-1 for location of indicator holes). ATS-1 Access User's Manual...
  • Page 134 Checking the Fuses Appendix A - Changing Mains Voltage Selection ATS-1 Access User's Manual...

  • Page 135: Appendix B - Rackmounting

    4. Align the rack mount spacer to the right side of the instrument. The spacer fits into the recess formed by the covers. Three holes in the spacer align wit three matching holes in the chassis; Do not insert screws at this time. ATS-1 Access User's Manual...

  • Page 136: Fixed Rack Mount

    Fasten the rack handle and spacer to the chassis with three 10-32 screws. c. Repeat Steps 4, a, and b on the left side of the instrument. d. Install the two handles on the brackets if desired, oriented toward the center of the instrument. ATS-1 Access User's Manual...
  • Page 137 (there are two screws on the right and left sides of each of the top and bottom covers, near the front four corners of the case). See Figure B-3. ATS-1 Access User's Manual...
  • Page 138 See Figure B-4. h. Repeat Steps 4, f, and g on the left side of the instrument. Install the two handles on the rack ear brackets, oriented toward the center of the instrument. ATS-1 Access User's Manual...

  • Page 139: Appendix C - Performing Internal Changes

    (total of 14 screws for each cover). You may need to also loosen or remove the handle. ATTENTION: Do NOT touch the components on the circuit boards. They can be easily damaged by static electricity. ATS-1 Access User's Manual...

  • Page 140: Changing To Alternate Connector Panels

    + on the circuit board. 10. Connect the Analyzer Input channel B cable to the analyzer B connector on the top circuit board. The wire with white insulation goes to the pin marked + on the circuit board. ATS-1 Access User's Manual...

  • Page 141: Swapping Speaker And Connector Panels

    4. Locate the two cables from the Generator Output connectors on the panel to the Generator circuit board on the bottom side of the chassis. Observe that each cable connects to the board connector nearest its panel connector. Disconnect these cables from the circuit board. ATS-1 Access User's Manual...
  • Page 142 (Location B in Figure C-1). The connector polarity is unimportant. (Generator circuit board as viewed from bottom of instrument) Location B Alternate speaker connectors Location A Front of instrument Figure C-1. Alternate Monitor speaker connector locations ATS-1 Access User's Manual...
  • Page 143 With both generator outputs on and a 1 kHz 1 volt signal, the measured voltages should agree within the instrument specification and the phase should read nearly zero degrees for all four possible input configuration selections: A-B, A-G, B-1, and B-G. ATS-1 Access User's Manual...

  • Page 144: Option Filter Installation

    5. Reconnect power to the unit and turn it on. Select AMPLITUDE function, INPUT A GEN, and use PANELS mode with analyzer setup parameters displayed to select the newly-installed filter(s). Verify their correct function by measuring their frequency response. ATS-1 Access User's Manual...

  • Page 145: Monitor Source Selection

    This is the same signal output by the rear panel ‘ANALYZER’ monitor. Changing from one monitor source to the other requires changing a resistor on a circuit board inside the ATS-1 Access. To make this change, proceed as described on the following page. ATS-1 Access User's Manual...
  • Page 146 Figure C-3 above. 3. Move this resistor to its alternate location (R2502). With the resistor in this position, the monitor signal will come from the final processed reading. 4. Replace the top cover. ATS-1 Access User's Manual...

  • Page 147: Appendix D - Specifications

    Rise/fall time Note 1 Calibration with other amplitude units is based upon an equivalent sinewave having the same Vpp amplitude. Note 2 System specification including contributions from both generator and analyzer. Generator load must be ≥600 Ω. ATS-1 Access User's Manual...
  • Page 148 Calibration with other amplitude units is based upon an equivalent sinewave having the same Vpp amplitude. Note 2 System specification including contributions from both generator and analyzer. Generator load must be ≥600 Ω. 200 Ω with option EURZ. Note 3 ATS-1 Access User's Manual...
  • Page 149 ±0.01% [±100 PPM] Accuracy Resolution 5 digits Minimum Input 25 mV Note 4 For fully specified performance. Usable with inputs as low as 10 mV. Readings are disabled for inputs below approximately 7 - 8 mV. ATS-1 Access User's Manual...
  • Page 150 Note 4 For fully specified performance. Usable with inputs as low as 10 mV. Readings are disabled for inputs below approximately 7 – 8 mV. Note 5 Combined with 22 Hz highpass per CCIR Rec 468. ATS-1 Access User's Manual...
  • Page 151 “1/V” fashion for inputs below 25 mV [-30 dBu] Note 6 System specification including contribution from generator. Generator residual THD may limit system performance below 25 Hz if output is >20.0 Vrms balanced, or 10.0 Vrms unbalanced. ATS-1 Access User's Manual...
  • Page 152 Alternate (interfering) channel input must be ≥5 mV. Note 8 For fully specified performance. Usable with inputs as low as 10 mV. Readings are disabled for inputs below approximately 7 – 8 mV. Note 9 System specification including contribution from generator. ATS-1 Access User's Manual...
  • Page 153 IEC/DIN or NAB Typically 3 – 6 seconds Typically 15 – 20 seconds Note 10 For fully specified performance. Usable with inputs as low as 10 mV. Readings are disabled for inputs below approximately 7 – 8 mV. ATS-1 Access User's Manual...
  • Page 154 The shielding performance of the cable will depend on the internal design of the cable, connector quality, and the assembly methods used. EMC compliance was evaluated using Audio Precision XLR type cables, part number CAB-AES. ATS-1 Access User's Manual...
  • Page 155 Analyzer section of Main Panel 3-8 Audible monitoring 3-6 % unit 3-17 - 3-18, 3-22 AUTO-TUNE 4-8 +10 dB key 3-2 AUTORANGE 4-41 -10 dB key 3-2 AUX1 4-3, 4-10 x10 key 3-2 AUX2 4-3, 4-10 1.00 dB/ISO 3-3 AVERAGE 4-26 2-sigma 4-33 Azimuth adjustments 20k OHM 4-39 C-2...
  • Page 156 CONTRAST Knob 3-5 Controlling the analyzer 3-15 - 3-16 FAST (sweep speed) 4-44 Controlling the generators 3-12 Filter Installation C-6 Crosstalk function 4-34 - 4-35 Filter Shapes Cursors 4-45 Shapes, Filter 1-6 - 1-7 Firmware version 2-5 FIX-TUNE 4-8, 4-23 Date, setting 3-10 FREQUENCY Controls 3-2 dB unit 3-17 - 3-18...
  • Page 157 Loading 3-14 Output connections 3-28 JIS wow-and-flutter standard 4-32 Output impedance 3-29 Overview 3-12 label, rear panel 1-9 Generator Level function 4-5 - 4-6 Section of Main Panel 3-8 Link testing 5-1 Generator monitor 3-16 Loading, generator 3-14 Generator output circuit 1-12 - 1-13 Loss measurement 4-29 GPIB Interface 3-27 Low display 4-35...
  • Page 158 Filters 1-5, 1-8 Printer configuration 3-10 IMD 1-3, 1-8 Printer port 3-26 Options label 1-5, 1-9 Printing 4-46 - 4-50 Output circuit, generator 1-12 - 1-13 Speed 4-49 Output configuration (analog) 3-13 Printing saved data 4-53 OUTPUT Keys 3-3 Priority of digital input selection 3-30 - 3-36 Outputs Program version 2-5 Analog analyzer 3-28...
  • Page 159 Setup Panel 3-10, 4-46 Understanding 4-11 Setups, saving and recalling 4-51 What is signal dominant? 4-13 SINAD function 4-22 - 4-24 THD+N Function 4-7 - 4-10 SLOW (sweep speed) 4-44 Third harmonic distortion measurements 5-4 SMPTE standard (IMD) 4-27 Time units 3-22 Speaker monitor 3-6 Time, setting 3-10 Holding range 4-41...

  • Page 160: Index

    NOTES: Index-6 Portable One Plus Access User's Manual...
  • Page 161 Audio Precision PO Box 2209 Beaverton, Oregon 97075-2209 Tel (503) 627-0832 Fax (503) 641-8906 US Toll Free 1-800-231-7350 email techsupport audioprecision.com Web www.audioprecision.com...

This manual is also suitable for:

Ats-1

Table of Contents