8080 Analog Communications Training Systems

Transcription

1 8080 Analog Communications Training Systems LabVolt Series Datasheet Festo Didactic en 240 V - 50 Hz 04/2018

2 Table of Contents General Description 2 Instrumentation Modules 3 Instructional Modules 3 Topic Coverage 3 Features & Benefits 4 List of Available Training Systems 4 Additional Equipment Required to Perform the Exercises 4 Optional Equipment 4 Optional Manual(s) 4 Available Training Systems 5 Equipment Description 11 Optional Equipment Description 26 General Description The Analog Communications Training Systems form a comprehensive program that enables instructors to teach the principles of analog communications, both in theory and in practice, using a variety of training environments. The Analog Communications Training Systems allow students to perform voltage and signal measurements, alignment calibration, and signal flow tracing. Students can build a communications system by connecting a generator to a receiver using a coaxial cable, which becomes the communication channel (or link). Coaxial cables eliminate radiation and noise interference. If a wireless system is desired, antennas can be used in place of the coaxial cable. Tests are performed on the complete system to ensure proper operation according to system standards and specifications. Noise can also be introduced to simulate atmospheric disturbances and to provide realistic signal-to-noise ratio evaluation. Once a communication system is set up, students can study such general system functions as interaction between individual units caused by circuit loading, matching, and tuning. A Spectrum Analyzer, Model 9405, allows students to observe and analyze base-band signals, as well as radio and intermediate frequency (RF and IF) signals in the frequency domain. Power for each module is distributed through self-aligning connectors when the modules are stacked. The Power Supply/Dual Audio Amplifier, Model 9401, is the base module of the systems. 2 Festo Didactic

3 Instrumentation Modules The six instrumentation modules of the Analog Communications Training Systems are: Model 9401 Power Supply / Dual Audio Amplifier Model 9402 Dual Function Generator Model 9403 Frequency Counter Model 9404 True RMS Voltmeter / Power Meter Model 9405 Spectrum Analyzer Model 9406 RF / Noise Generator These modules are designed for skills training in telecommunications and are part of the Analog and Digital Communications Systems. Each instrument is fully protected against short circuits and misconnections made by the student. The operation and use of these instruments is covered in Volume 1, Instrumentation, of the Analog Communications Training System. Later in the same program, and in the Digital Communications Training System, Model 8085, students use the instruments to make measurements in laboratory experiments performed on AM, FM, and digital communications systems. The Frequency Counter, True RMS Voltmeter / Power Meter, and Spectrum Analyzer mentioned above can be replaced with the Data Acquisition and Management for Telecommunications (LVDAM-COM), Model The LVDAM-COM system is a modern and versatile equipment for measuring, observing, and analyzing signals in telecommunications systems. It consists of a set of computer-based instruments running on a Pentium-type personal computer under the Microsoft Windows operating environment. Note that the LVDAM-COM system also includes a dual trace oscilloscope with a 40-MHz bandwidth. Instructional Modules The six instructional modules of the Analog Communications Training Systems are: Model 9410 AM/DSB/SSB Generator Model 9411 AM/DSB Receiver Model 9412 SSB Receiver Model 9413 Direct FM Multiplex Generator Model 9414 Indirect FM/PM Generator Model FM/PM Receiver Fault switches and test points inside the modules allow fault insertion and observation of signals at various stages in the circuit. Both the fault switches and the test points are accessed through a hinged panel in the top cover. A small, hinged, lockable cover inside the module limits access to the fault switches. All system modules are stackable with the Power Supply / Dual Audio Amplifier, Model 9401, in the bottom position. Self-aligning, multi-pin connectors located at the top and bottom of each module distribute power throughout the system. When used with the Power Supply / Dual Audio Amplifier, the instructional modules are effectively protected against all misconnections and short circuits. Topic Coverage Basic Concepts and Equipment Spectral Analysis Festo Didactic 3

4 Amplitude Modulation and Frequency Modulation (Generation and Reception of Signals) Double- and Single-Sideband Modulation Narrowband Angle Modulation Troubleshooting AM and FM Communication Systems Frequency Division Multiplexing Features & Benefits One of the most comprehensive of its kind in the marketplace Uses the latest communications technologies to teach analog communications, both in theory and in practice, for colleges and universities Provides hands-on exercises in the generation, transmission, and reception of analog communications signals System design allows voltage and signal measurements, alignment, calibration, and signal tracing Coaxial cables eliminate radiation and noise interference Noise can be introduced to simulate atmospheric disturbances, and to provide realistic signal-to-noise evaluation Switches to insert faults and teach troubleshooting Symbols and diagrams specific to each module are clearly silk-screened on the faceplates Comprehensive curriculum with hands-on exercises included Estimated program duration: 140 hours (all 3 volumes) List of Available Training Systems Qty Description Model number 1 Analog Communications Training System A 1 Analog Communications Training System with LVDAM-COM 8080-AA Additional Equipment Required to Perform the Exercises Qty Description Model number 1 1 Training on Instrumentation, 0.9 day TF 1 2 Training on AM / DSB / SSB, 1.6 days TF 1 3 Training on FM / PM, 1.2 days TF Optional Equipment Model Qty Description number 1 Dust Cover for Model Optional Manual(s) Model Qty Description number 1 Analog Communications Training System (Manuals on CD-ROM) A0 1 Optional product training. Price provided on demand. For details and options, contact services.didactic@festo.com. 2 Optional product training. Price provided on demand. For details and options, contact services.didactic@festo.com. 3 Optional product training. Price provided on demand. For details and options, contact services.didactic@festo.com. 4 Festo Didactic

5 Available Training Systems Analog Communications Training System A The Analog Communications Training System consists of six instructional modules supported by six instrumentation modules. Correlated student manuals guide students through hands-on learning exercises. Individual system modules offer applications in the generation, transmission, and reception of amplitude, double sideband, single sideband, frequency, and phase (AM, DSB, SSB, FM, and PM) modulated signals. To complete these exercises, a dual-trace oscilloscope is required (purchased separately). The Dual Trace Oscilloscope, Model 797, is recommended. Fault switches are provided in each instructional module. They enable malfunctions to be inserted by the instructor to develop and enhance the troubleshooting skills of students. Faults can be used while students train on the individual modules, or troubleshooting can be expanded to the communications system when the modules are interconnected. A door on the top of each instructional module provides access to circuit boards, test points, and fault insertion switches. List of Equipment Qty Description Model number 1 Cables and Accessories Power Supply / Dual Audio Amplifier A 1 Dual Function Generator Frequency Counter True RMS Voltmeter / Power Meter Spectrum Analyzer RF/Noise Generator AM/DSB/SSB Generator AM/DSB Receiver SSB Receiver Direct FM Multiplex Generator Indirect FM/PM Generator FM/PM Receiver Festo Didactic 5

6 List of Manuals Manual Description number Instrumentation (Student Manual) Analog Communications (Instructor Guide) AM / DSB / SSB (Student Manual) FM / PM (Student Manual) Table of Contents of the Manual(s) Instrumentation (Student Manual) ( ) 1-1 The Dual Function Generator 1-2 The True RMS Voltmeter/Power Meter as a Voltmeter 1-3 The True-RMS Voltmeter/Power Meter as a Power 1-4 The Dual Audio Amplifier 2-1 Introduction to Spectral Analysis 2-2 Horizontal Calibration of the Spectrum Analyzer 2-3 Vertical Scales of the Spectrum Analyzer 2-4 Harmonic Composition of a Signal 2-5 Spectral Analysis of a Signal 3-1 Amplitude Modulation 3-2 Frequency Modulation AM / DSB / SSB (Student Manual) ( ) 1-1 An AM Communications System 1-2 Familiarization with the AM Equipment 1-3 Frequency Conservation of Baseband Signals 2-1 An AM Signal 2-2 Percentage Modulation 2-3 Carrier and Sideband Power 3-1 The RF Stage Frequency Response 3-2 The Mixer and Image Frequency Rejection 3-3 The IF Stage Frequency Response 3-4 The Envelope Detector 4-1 DSB Signals 4-2 Reception and Demodulation of DSB Signals 5-1 Generating SSB Signals by the Filter Method 5-2 Reception and Demodulation of SSB Signals 6-1 Troubleshooting Techniques 6-2 Troubleshooting the AM / DSB section of the AM / DSB / SSB Generator 6-3 Troubleshooting the SSB section of the AM / DSB / SSB Generator 6-4 Troubleshooting the AM / DSB Receiver 6-5 Troubleshooting the SSB Receiver 6-6 Troubleshooting an AM / DSB Communications System 6-7 Troubleshooting an SSB Communications System FM / PM (Student Manual) ( ) 1-1 Time-Domain Observations 1-2 Frequency-Domain Observations 6 Festo Didactic

7 2-1 The FM Modulation Index 2-2 Power Distribution 2-3 Determination of the FM Bandwidth 3-1 Basic Principles of Narrow Band Angle Modulation 3-2 The Relationship between FM and PM 3-3 Spectral Characteristics 4-1 Frequency Multiplication 4-2 Spectral Analysis 5-1 Direct Method of Generating FM Signals 5-2 Indirect Method of Generating FM Signals 6-1 The Fixed-Frequency Receiver 6-2 The Tunable Receiver 7-1 Stereophonic Frequency Modulation 7-2 Stereophonic Reception 7-3 Multiple Modulation 7-4 Regulations Concerning FM Broadcasting 8-1 Improvement of the Signal / Noise Ratio 8-2 Preemphasis and Deemphasis 9-1 Techniques of Troubleshooting 9-2 Troubleshooting the Direct FM Multiplex Generator 9-3 Troubleshooting the Indirect FM / PM Generator 9-4 Troubleshooting the FM / PM Receiver 9-5 Troubleshooting the WBFM System Additional Equipment Required to Perform the Exercises Model Qty Description number 1 Dual Trace Oscilloscope System Power Requirement Space required 600 W 4 m² (43 ft²) 71.1 kg (157 lb) Festo Didactic 7

8 Analog Communications Training System with LVDAM-COM 8080-AA The Analog Communications Training System with LVDAM-COM is a comprehensive training system that enables instructors to teach the principles of analog communications, both in theory and in practice, using a variety of training environments. It is part of a series of advanced systemlevel programs that is one of the most comprehensive of its kind in the marketplace. The LVDAM-COM software is a set of computer-based instruments for telecommunications. It includes an Oscilloscope, a Frequency Counter, a True RMS Voltmeter, and a Spectrum Analyzer. The LVDAM-COM software is used with the Virtual Test Equipment Interface, Model 9407, to perform time-domain and frequency-domain measurements in the Analog Communications Training System, Model 8080, and the Digital Communication Training System, Model The LVDAM-COM software can be configured by the user for operation in any of the following four languages: English, French, Spanish, and Bahasa (Indonesia). LVDAM-COM can be installed on a Pentium-type computer. Refer to the specifications section of the Model 9407 for the computer requirements. List of Equipment Qty Description Model number 1 Cables and Accessories Power Supply / Dual Audio Amplifier A 1 Dual Function Generator RF/Noise Generator Data Acquisition and Management for Telecommunications (LVDAM-COM) A 1 AM/DSB/SSB Generator AM/DSB Receiver SSB Receiver Direct FM Multiplex Generator Indirect FM/PM Generator FM/PM Receiver Festo Didactic

9 List of Manuals Manual Description number Instrumentation (Student Manual) Analog Communications (Instructor Guide) AM / DSB / SSB (Student Manual) FM / PM (Student Manual) Data Acquisition and Management System (User Guide) E0 Virtual Test Equipment Interface (Instruction Manual) D0 Computer-Based Instruments (User Guide) E0 Table of Contents of the Manual(s) Instrumentation (Student Manual) ( ) 1-1 The Dual Function Generator 1-2 The True RMS Voltmeter/Power Meter as a Voltmeter 1-3 The True-RMS Voltmeter/Power Meter as a Power 1-4 The Dual Audio Amplifier 2-1 Introduction to Spectral Analysis 2-2 Horizontal Calibration of the Spectrum Analyzer 2-3 Vertical Scales of the Spectrum Analyzer 2-4 Harmonic Composition of a Signal 2-5 Spectral Analysis of a Signal 3-1 Amplitude Modulation 3-2 Frequency Modulation AM / DSB / SSB (Student Manual) ( ) 1-1 An AM Communications System 1-2 Familiarization with the AM Equipment 1-3 Frequency Conservation of Baseband Signals 2-1 An AM Signal 2-2 Percentage Modulation 2-3 Carrier and Sideband Power 3-1 The RF Stage Frequency Response 3-2 The Mixer and Image Frequency Rejection 3-3 The IF Stage Frequency Response 3-4 The Envelope Detector 4-1 DSB Signals 4-2 Reception and Demodulation of DSB Signals 5-1 Generating SSB Signals by the Filter Method 5-2 Reception and Demodulation of SSB Signals 6-1 Troubleshooting Techniques 6-2 Troubleshooting the AM / DSB section of the AM / DSB / SSB Generator 6-3 Troubleshooting the SSB section of the AM / DSB / SSB Generator 6-4 Troubleshooting the AM / DSB Receiver 6-5 Troubleshooting the SSB Receiver 6-6 Troubleshooting an AM / DSB Communications System 6-7 Troubleshooting an SSB Communications System Festo Didactic 9

10 FM / PM (Student Manual) ( ) 1-1 Time-Domain Observations 1-2 Frequency-Domain Observations 2-1 The FM Modulation Index 2-2 Power Distribution 2-3 Determination of the FM Bandwidth 3-1 Basic Principles of Narrow Band Angle Modulation 3-2 The Relationship between FM and PM 3-3 Spectral Characteristics 4-1 Frequency Multiplication 4-2 Spectral Analysis 5-1 Direct Method of Generating FM Signals 5-2 Indirect Method of Generating FM Signals 6-1 The Fixed-Frequency Receiver 6-2 The Tunable Receiver 7-1 Stereophonic Frequency Modulation 7-2 Stereophonic Reception 7-3 Multiple Modulation 7-4 Regulations Concerning FM Broadcasting 8-1 Improvement of the Signal / Noise Ratio 8-2 Preemphasis and Deemphasis 9-1 Techniques of Troubleshooting 9-2 Troubleshooting the Direct FM Multiplex Generator 9-3 Troubleshooting the Indirect FM / PM Generator 9-4 Troubleshooting the FM / PM Receiver 9-5 Troubleshooting the WBFM System Computer-Based Instruments (User Guide) (36220-E0) 1 Familiarization with the True RMS Voltmeter and Frequency Counter 2 Familiarization with the Oscilloscope 3 Familiarization with the Spectrum Analyzer Additional Equipment Required to Perform the Exercises Qty Description Model number 1 Personal Computer A System Power Requirements Space required 600 W 4 m² (43 ft²) 71.1 kg (157 lb) 4 Refer to the Computer Requirements in the System section of this datasheet if the computer is to be provided by the end-user. 10 Festo Didactic

11 Equipment Description Cables and Accessories The Cables and Accessories set contains the various cables and accessories required to perform the exercises in the program training manuals. The accessories package contains the following parts: three different lengths of coaxial cables terminated with BNC connectors whip, pigtail, and folded dipole antennas BNC T-connectors resistive loads with BNC connectors headset These accessories come in a convenient plastic storage case. BNC Coaxial Cables Antennas Accessories Dimensions (H x W x D) 40 cm, Qty: 6 75 cm, Qty: cm, Qty: 4 Whip, Qty: 2 Pigtail, Qty: 2 Folded-Dipole, Qty: 1 Load 50 S BNC, Qty: 2 BNC T-Connector, Qty: 4 Headset, Qty: 1 Storage Case 200 x 445 x 62 mm (7.9 x 17.5 x 2.4 in) 2 kg (4.4 lb) Power Supply / Dual Audio Amplifier A The Power Supply / Dual Audio Amplifier module forms the physical base for the analog and digital communications training systems, and can be used in several other training systems. It is double-width to accommodate two instructional modules or two instrument modules in a side-byside configuration. A two-channel audio amplifier with headphone jacks and speakers accommodates FM stereo and narrowband FM and AM receiver outputs. The power supply distributes power to the complete system and provides three regulated dc voltage outputs (15 V 0.5 A; -15 V 0.5 A; +5 V 1 A) on the faceplate. Also unregulated voltages are distributed to the system modules through a connector located on each module. These unregulated voltages are regulated within each module to provide the required voltages. Each regulated supply has an LED indicator that shuts off if the supply is overloaded due to equipment malfunction or if a faulty power connection is made to external equipment. Festo Didactic 11

12 Power Requirement Current Service Installation Power Outputs Unregulated Power Bus Regulated Front Panel Dual Audio Amplifier Rating Bandwidth Input Impedance Nominal Output Power Sensitivity (at nominal output power) Output Impedance (intermediate outputs) Maximum Output Level (open-circuit) Protection AC Line Input DC Regulated Outputs DC Unregulated Outputs Dimensions (H x W x D) 2 A Standard single-phase ac outlet ±25 V typ. 3 A max; -25 V typ. 3 A max.; +11 V typ. 5 A max. ±15 V 0.5 A; + 5 V 1 A 50 Hz to 15 khz 10 kω 250 mw 140 mw 1 kω 20 V p-p Circuit breaker Foldback current-limiting Circuit breaker 104 x 687 x 305 mm (4.1 x 27 x 12 in) 15.8 kg (34.8 lb) Dual Function Generator The Dual Function Generator consists of two independent function generators (A and B), each capable of generating a sine-wave signal, a square-wave signal, a triangular-wave signal, a sawtooth-wave signal, and a pulse signal with variable pulse-width. The signal frequency can be varied from 10 Hz to 100 khz through four ranges. A digital display is pushbutton-selectable between generators A and B to monitor the frequency of each generator. Each generator output signal level is continuously variable and may be attenuated by push buttonselected switch attenuators. TTL output signals are provided to synchronize external equipment, such as an oscilloscope. Generator A may be frequency-modulated by a signal from generator B or from an external source. The module is fully protected against short circuits and misconnections. Students use the instruments to make measurements in laboratory experiments performed on AM, FM, and digital communications systems. Power Requirement Generators (A & B) Rating Waveforms Pulse Duty Cycle 10 to 90 % Frequency Ranges Frequency Display (switchable between A & B) Output Impedance Output Level (open circuit) Attenuator Synchronization Outputs Frequency Modulation (Channel A only) Input Impedance Maximum Frequency Deviation ±25 V typ. 3 A max; -25 V typ. 3 A max.; +11 V typ. 5 A max. Sine, triangle, square, sawtooth, or pulse Hz, Hz, 1-10 khz, khz 4 digits 50 Ω 10 mv p-p to 10 V p-p 0, 20, or 40 db One for each channel (SYNC/TTL) 100 kω 50 % of each side of the rest frequency 12 Festo Didactic

13 Input Level for Maximum Deviation Dimensions (H x W x D) 10 V p-p 162 x 330 x 300 mm (6.4 x 13 x 11.8 in) 4.4 kg (9.7 lb) Frequency Counter The Frequency Counter is a directcounting frequency counter with an 8- digit display. The frequency counter has three functions: it determines the frequency of the input signal and displays the frequency in Hz, khz, or MHz, it determines the period of the input signal and displays the period in s or ms, and it works as an event counter when the counter function is selected. The frequency/period resolution is switch-selectable from 0.1 to 100 Hz (0.1 to 100 ns). As an event counter, each negative-going transition of the input signal adds one to the cumulative count displayed. The input signal may be attenuated by a switch attenuator. The module is fully protected against short circuits and misconnections. Students use the instruments to make measurements in laboratory experiments performed on AM, FM, and digital communications systems. Power Requirement Rating Input Frequency Range Input Period Range +25 V 425 ma; -25 V 325 ma 10 Hz - 10 MHz, 10 MHz MHz 0.1 s 4 µs (10 Hz-2.5 MHz) Count Range Input Impedance Sensitivity (Sine Wave RMS ) Attenuator Resolution Frequency Display Dimensions (H x W x D) 1 MΩ 10 Hz MHz: 25 mv; 100 MHz-200 MHz: 60 mv 0, 20 or 40 db 0.1, 1, 10, 100 Hz (ns) 8 digits 112 x 330 x 300 mm (4.4 x 13 x 11.8 in) 3.2 kg (7 lb) True RMS Voltmeter / Power Meter The True-RMS Voltmeter / Power Meter is a dual function instrument used to measure RMS voltage or signal power in communications systems. Voltage and power can be measured through four ranges on a 3½ digit panel display. The function is switch-selectable on the front panel. The input signal frequency range is 20 Hz to 12 MHz. An automatic zeroadjust function readjusts the meter s zero at regular time intervals. This feature provides precise measurements over a wide range of temperature. Festo Didactic 13

14 The module is fully protected against short circuits and misconnections. Students use the instruments to make measurements in laboratory experiments performed on AM, FM, and digital communications systems. Power Requirement Rating Measurement Bandwidth Input Impedance Voltage Ranges Power Ranges Accuracy (10 mv and 100 mv Ranges) Accuracy (1 V and 10 V Ranges) Dimensions (H x W x D) +25 V 125 ma; +11 V 350 ma; -25 V 75 ma 20 Hz to 12 MHz 1 MΩ 10 mv, 100 mv, 1 V, 10 V -27, -7, +13, +33, (50 Ω input) ±3 % (20 Hz to 12 MHz) ±5 % (20 Hz to 12 MHz) 112 x 330 x 300 mm (4.4 x 13 x 11.8 in) 3.0 kg (6.7 lb) Spectrum Analyzer The Spectrum Analyzer is used for signal observation of the communications system in the frequency domain. It is a frequencyselective instrument that allows the power level of each frequency component of a signal to be displayed on a regular oscilloscope: a dual trace oscilloscope or a single trace oscilloscope with an external sweep input having a sensitivity of 1 V/div. is required. The Spectrum Analyzer has two selectable input frequency ranges: dc to 30 MHz, and 85 to 115 MHz. The center frequency is indicated on a 3½ digit display. The Spectrum Analyzer has an output for use with the optional Dual Trace Oscilloscope, Model 797, or the X-Y Recorder, Model Two digital memories of 1024 horizontal points by 256 vertical levels provide a stable display at a refresh rate of 30 Hz. The frequency span is switch-selectable in five ranges from 2 khz to 1 MHz per volt. With the oscilloscope set at 1 V/div., total spans of 20 khz to 10 MHz are possible. The bandwidth resolution is automatically optimized between 100 Hz and 50 khz. Inputs to the spectrum analyzer may be attenuated by 40 db in five steps. The input impedance is switch-selectable between 50 Ω and 1 MΩ. The input signal may be displayed in linear or logarithmic form (10 db/v) up to a maximum display range of 60 db. The module is fully protected against short circuits and misconnections. Students use the instruments to make measurements in laboratory experiments performed on AM, FM, and digital communications systems. Power Requirements Power Requirements Rating Input Frequency Range Input Impedance Input Signal Level +25 V 750 ma +11 V 600 ma -25 V 475 ma 0-30 MHz (500 Hz minimum) and MHz 50 Ω or 1 MΩ -70 to +30 dbm (50 Ω input) 14 Festo Didactic

15 Maximum Input Signal Levels 7 V (peak AC + DC) at 50 Ω impedance 15 V (peak AC + DC) at 1 MΩ impedance Frequency span (Oscilloscope/Plotter at 1 V/div.) 0 Hz; 2, 10, 50, 200 khz; 1 MHz/div. Resolution Bandwidth (3 db) 100, 500 Hz; 2, 20, 50 khz (automatic selection) Frequency Markers 10, 100 khz; 1, 10 MHz Marker Frequency Stability ±0.003 %/ C Frequency Measurement Resolution 1 khz (using 10 khz markers) Dynamic Range (input signal measurements 60 db Selectivity (60 db/3 db) Better than 13:1 Output Display External oscilloscope set the X-Y mode at 1 V/div. and/or X-Y (oscilloscope and plotter not supplied) Output Mode HOLD/LIVE Output Scale Linear or Log (10 db/v) Output Level Variable up to 10 db from CAL position Memories (A et B) 1024 vertical points x 256 horizontal levels Oscilloscope Outputs X: 0 to 10 V; Y: 0 to 6 V Plotter Outputs X: 0 to 10 V; Y: 0 to 6 V; ground Input/Output Signal Connectors BNC (except plotter output, which is 2 mm banana jacks) Accessories One 2 m (6.5 ft) plotter connection cable Dimensions (H x W x D) 162 x 330 x 315 mm (6.4 x 13 x 12.4 in) 5.6 kg (12.3 lb) RF/Noise Generator communications system. This generator has FM and AM capabilities. The RF/Noise Generator contains two independent generators capable of generating a tone signal in the frequency range from 100 khz to 32 MHz and a "white" noise signal in selected frequency bands from 0 to 11.2 MHz. The radio frequency (RF) generator produces a signal output in five frequency ranges to cover the frequencies in the analog The noise generator provides white noise in five independent frequency bands. The noise output may be used for measuring the frequency response of filters or the signal-to-noise ratio in any part of the system. The module is fully protected against short circuits and misconnections. Students use the instruments to make measurements in laboratory experiments performed on AM, FM, and digital communications systems. RF Generator Rating Frequency Ranges Output Voltage (across 50 Ω) Output impedance SYNC Output Level Amplitude Modulation Input Level Amplitude Modulation Input Impedance Frequency Modulation Input Level Frequency Modulation Input Impedance Noise Generator Rating Frequency Ranges khz, MHz, 1-3 MHz, 3-10 MHz, MHz 100 mv p-p 50 Ω 1.5 V p-p min. 1 V p-p 10 kω 1 V p-p 10 kω Audio: 2 Hz - 20 khz Audio/RF: 0 Hz - 2 MHz Festo Didactic 15

16 Output Voltage (across 50 Ω) Output Impedance Dimensions (H x W x D) AM IF Noise: khz SSB RF Noise: MHz FM IF Noise: MHz 0.5 V rms 50 Ω 162 x 330 x 300 mm (6.4 x 13 x 11.8 in) 4 kg (8.8 lb) Data Acquisition and Management for Telecommunications (LVDAM-COM) A The Data Acquisition and Management for Telecommunications (LVDAM-COM) is a computer-based system for measuring, observing, and analyzing signals in telecommunications systems. It allows training in both analog and digital telecommunications systems using modern and versatile measuring instruments. A user manual provided with the LVDAM-COM system allows students to quickly familiarize with the instruments. The LVDAM-COM system consists of the Virtual Test Equipment Interface module and the Data Acquisition and Management for Telecommunications software (LVDAM-COM). The LVDAM-COM system is a standard feature in the Analog Communications Training System with LVDAM-COM, Model 8080-A, and Digital Communications Training System with LVDAM-COM, Model 8085-B. The LVDAM-COM system can replace the conventional instruments (Frequency Counter, Model 9403, True-RMS Voltmeter / Power Meter, Model 9404, and Spectrum Analyzer, Model 9405) in the Analog Communications Training System, Model 8080, and Digital Communications Training System, Model Virtual Test Equipment Interface The Virtual Test Equipment Interface (VTEI) module links the personal computer running the LVDAM-COM software with the Analog and Digital Training Systems. Data exchange between the VTEI module and the personal computer is made through a standard parallel port. The VTEI module is designed to meet the high frequency signal requirements for communications systems. It provides the necessary hardware to implement a dual trace oscilloscope, a Spectrum analyzer, a true-rms voltmeter, and a frequency counter. All inputs are fitted with BNC connectors and are fully protected against short circuits and misconnections made by the students. An instruction manual provides detailed information about the VTEI module. 16 Festo Didactic

17 LVDAM-COM Software The LVDAM-COM software consists of a complete set of instruments. Each instrument appears as a window on the computer screen. Computer-based instruments provide instructors with the opportunity to clearly demonstrate concepts that are usually presented using traditional textbook methods and static drawings. They also enhance the overall presentation of course material with built-in capabilities for waveform observation, data storage, and graph plotting. The various instruments of the LVDAM-COM system are briefly described in the next section of this data sheet. The LVDAM-COM software can operate in either of the following modes: acquisition and simulation. In the acquisition mode, the input signals are measured by the VTEI module and then transmitted to the LVDAM-COM software through the computer s parallel port. In the simulation mode, input signals are generated by the computer using user-defined simulation parameters. When used in conjunction with the LVSIM -COM - Virtual Laboratory Equipment for Analog Communications, Model 9480, a third mode, referred to as virtuality, is available. In this mode, input signals are generated by the computer using simulation parameters that are produced by the LVSIM -COM software. See the data sheet of Model 9480 for additional information. The LVDAM-COM software configuration, the recorded data, and the user-defined simulation parameters can be saved to files. All display screens obtained with LVDAM-COM can be printed out or pasted in any document. Frequency Counter The Frequency Counter has three functions. It can measure the frequency of the input signal and display the frequency in Hz, khz, or MHz. It can determine the period of the input signal and displays the result in ns, μs, or ms. It can also be used as an event counter. The Frequency Counter resolution is software-selectable from 0.1 to 100 Hz. True RMS Voltmeter The True RMS Voltmeter is a dual function instrument that can measure the true RMS voltage or power of telecommunications signals. Voltage and power can be measured using any one of four software-selectable ranges (10 mv, 100 mv, 1 V, 10 V, and -27 dbm, -7 dbm, +13 dbm, +33 dbm). Festo Didactic 17

18 Spectrum Analyzer The Spectrum Analyzer is used for frequency-domain observation of telecommunications signals. It is a frequency-selective instrument that allows the power level of the frequency components in the input signal to be displayed on a graduated screen. The Spectrum Analyzer has two selectable frequency ranges: 0 to 30 MHz, and 85 to 115 MHz. The center frequency can be selected directly by typing the frequency on the keyboard or by using the special Seek function which locates the closest spectral component within the selected frequency range. The total frequency span of the main screen can be varied from 20 khz to 10 MHz. The Spectrum Analyzer includes a special window which allows the student to visualize all the spectral information contained in the selected frequency range. A portion of this spectral data can be zoomed in the main screen for precise analysis. The input impedance is selectable between 50 Ω and 1 MΩ. The input signal can be displayed using linear or logarithmic scales up to a maximum display range of 60 db. Oscilloscope The Oscilloscope is used for timedomain observation of telecommunications signals. It has two input channels and an external-trigger input. The Oscilloscope has the same features as a conventional oscilloscope (scales, time bases, trigger level, channel math, X & Y display), to which have been added digital properties such as auto scaling, cursors, waveforms memorization capabilities, and more. Data Table and Graph The Data Table window interacts with the four other computer-based instruments (Oscilloscope, Spectrum Analyzer, Frequency Counter, and True RMS Voltmeter) to record data in a table. Each of the four instruments contains a data area, and each cell in that data area can be linked to a column of the Data Table. With the press of a button, the data contained in the instrument is transferred into the Data Table. Once data is acquired, different graphs can be generated using the Graph Window. 18 Festo Didactic

19 List of Manuals Manual Description number Data Acquisition and Management System (User Guide) E0 Virtual Test Equipment Interface (Instruction Manual) D0 Computer-Based Instruments (User Guide) E0 Table of Contents of the Manual(s) Computer-Based Instruments (User Guide) (36220-E0) 1 Familiarization with the True RMS Voltmeter and Frequency Counter 2 Familiarization with the Oscilloscope 3 Familiarization with the Spectrum Analyzer Additional Equipment Required to Perform the Exercises Qty Description Model number 1 Personal Computer A Power Requirements Current Service Installation Frequency Counter Input Frequency Range Input Period Range Count Range Input Impedance Sensitivity (Sine Wave RMS ) Attenuator Resolution True RMS Voltmeter Input Impedance Voltage Ranges 1 A Standard single-phase ac outlet 10 Hz MHz 5 ns s (28 bits) 1 MΩ 10 Hz to 140 MHz: 60 mv MHz: 200 mv 0, 20, or 40 db 0.1, 1, 10, 100 Hz 1 MΩ 10 mv, 100 mv, 1 V, 10 V Power Ranges -27 dbm, -7 dbm, +13 dbm, +33 dbm, (0 dbm = 1 mw in 50 Ω) Operating Range Accuracy 5% Crest Factor 5 Spectrum Analyzer Input Frequency Ranges Input Impedance Input Signal Level Maximum Input Signal Level Frequency Span Resolution Bandwidth (3 db) Dynamic Range (input signal measurements) 50 Hz - 12 MHz 0-30 MHz (500 Hz min.) and MHz 50 Ω or 1 MΩ (software selectable) -70 to +30 dbm (50 Ω input) 10 V peak 0 Hz/div; 2 khz/div - 1 MHz/div 100, 500 Hz; 2, 20, 50 khz (automatically selected) 60 db Selectivity (60 db/3 db) Better than 13:1 View Scale Oscilloscope Channels 1 & 2 Impedance Coupling Bandwidth (Channel 1) Bandwidth (Channel 2) AC Coupling (Lower Limit) Linear or Log 1 MΩ AC or DC 40 MHz 20 MHz 16 Hz 5 Refer to the Computer Requirements in the System section of this datasheet if the computer is to be provided by the end-user. Festo Didactic 19

20 Voltage Range Time base Oscilloscope Triggering Source Slope Oscilloscope External Trigger Impedance Voltage Ranges Coupling Bandwidth Oscilloscope A/D Conversion Resolution Maximum Sampling Rate (Channel 1) Maximum Sampling Rate (Channel 2) Computer Requirements Dimensions (H W D) AM/DSB/SSB Generator mv/div - 5 V/div 0.2 μs/div s/div Channel 1, Channel 2, External Positive or Negative 1 MΩ ±1 V and ±5 V AC or DC 40 MHz 10 bits 80 MSPS 40 MSPS A currently available personal computer with USB 2.0 ports and a parallel port, running under one of the following operating systems: Windows 7 or Windows x 205 x 580 mm (13.6 x 8.1 x 22.8 in) TBE The AM/DSB/SSB Generator provides training in AM, DSB and SSB transmission. There are two signal outputs from the module: an AM or DSB signal is produced at one, and an SSB signal is produced at the other. The base-band input signal is common to both outputs. The AM/DSB generator operates in the commercial AM broadcast band of 535 to 1605 khz, while the SSB generator produces radio signals in the 80 meter (3.7 to 4.0 MHz) band reserved for amateur radio operators. The AM/DSB function allows experimentation with techniques related to amplitude modulation and the effects of linear and non-linear overmodulation. The student is able to observe the information contained in the sidebands and to show the effect of carrier suppression (up to 40 db) in DSB generation. The SSB function and the relationship between the SSB signal and the AM or DSB signals can be clearly demonstrated. Modern techniques of sideband generation using a suppressed carrier modulator are investigated. Sideband filtering techniques and power amplification are demonstrated. Use of the beat frequency oscillator (BFO) and variable frequency oscillator (VFO) in the generation of an SSB signal are also studied. Power Requirement Audio Input Bandwidth Impedance Level AM/DSB Section Output Frequency Range Output Impedance Output Power +25 V ma - DC; -25 V - 75 ma - DC 20 Hz to 20 khz 10 kω 500 mv p-p (maximum for normal operation) 400 to 1800 khz 50 Ω Less than 100 mw (no permit required) 20 Festo Didactic

21 Controls Carrier level, RF tuning, RF gain Carrier Suppression (with maximum Input level) 35 db SSB Section Output Frequency Range to 4.0 MHz Output Impedance 50 Ω Output Power Less than 100 mw (no permit required) Controls BFO tuning, VFO tuning, RF gain BFO Tuning Range 450 to 460 khz VFO Tuning Range 4.2 to 4.5 MHz IF Frequency 455 khz Intermediate Outputs BFO, mixer, IF, VFO Carrier Suppression (with maximum Input level) 35 db Faults 12, switch-insertable Test Points Test points 17 Indicator Power ON Dimensions (H x W x D) 162 x 330 x 300 mm (6.4 x 13.0 x 11.8 in) 4.2 kg (9.2 lb) AM/DSB Receiver The AM/DSB Receiver teaches the steps involved in AM- and DSBmodulated RF signal reception. The receiver can have as input the AM/ DSB/SSB Generator signals or radio signals received via an antenna. The RF input signal with a frequency between 535 to 1605 khz is applied through a BNC connector and may be connected to the AM/DSB/SSB Generator. A high-impedance input is furnished for connection to an external antenna. Connectors allow the study of intermediate signals in the RF section, at the mixer output, at the intermediate frequency (IF) output, and at the audio output. The audio output allows observation of the demodulated signal. Students may easily observe the action of the automatic gain control (AGC) and the operation of the various detectors: envelope (ENV), synchronous (SYNC), and Costas loop (COSTAS). Students may observe the audio output signal directly or measure it with the instrumentation modules. Power Requirement RF Section Tuning Range Input Impedance Control Intermediate Outputs RF Input Level Sensitivities ENV Detector SYNC & COSTAS Detectors IF Section Operating Frequency Bandpass AUX Input impedance Control Intermediate Output +25 V ma - DC; -25 V - 75 ma - DC 535 khz to 1605 khz 1 input at 50 Ω, 1 input at 50 kω RF tuning RF filter, local oscillator, mixer 300 µv (Typical for both inputs for 100 mv p-p signal at audio output) 60 µv (Typical for both inputs for 100 mv p-p signal at audio output) 455 khz 5 khz (nominal) 50 Ω AGC switch IF Festo Didactic 21

22 Detectors AM: ENV or SYNC, DSB: COSTAS (switch-selectable) Audio Output Bandwidth 300 Hz to 5 khz Impedance 1 kω Faults 8, switch-insertable Test Points 17 Indicator Power ON Dimensions (H x W x D) 112 x 330 x 300 mm (4.4 x 13.0 x 11.8 in) 3.6 kg (7.9 lb) SSB Receiver high-impedance input for signals from an external antenna. The SSB Receiver offers instruction in SSB reception techniques and may be used with the AM / DSB / SSB Generator to establish a transmitterreceiver system. The SSB signal may be injected via one of two inputs: a low-impedance input for signals from the AM / DSB / SSB Generator, or a The receiver operates in the frequency band from 3.7 to 4.0 MHz using two frequency conversion stages. The first (RF section) stage contains a VFO, adjustable between 4.2 and 4.5 MHz. The second (IF section) stage contains the BFO, the frequency of which is adjustable between 450 and 460 khz. The SSB receiver contains an AGC circuit and an auxiliary input to inject a signal directly into the IF stage. Connectors allow students to study the RF output signal at the VFO output, the mixer output, the IF output, the BFO output, and the audio output. Power Requirement RF Section Tuning Range Input Impedance Control VFO Tuning Range Intermediate Outputs RF Input Level Sensitivities +25 V ma - DC; -25 V ma - DC to 4.0 MHz 1 input at 50 Ω, 1 input at 50 kω VFO tuning 4.2 to 4.5 MHz VFO, mixer 50 Ω input 10 mv (typical for 100 mv p-p signal at audio output) 50 kω input 2.5 mv (typical for 100 mv p-p signal at audio output) IF Section Operating Frequency Bandpass AUX Input Impedance Controls BFO Tuning Range Intermediate Outputs Audio Output Bandwidth Impedance Faults Test Points 14 Indicator 455 khz 6 khz (nominal) 50 Ω BFO tuning, AGC switch 450 to 460 khz IF, BFO 300 Hz to 3 khz 1 kω 8, switch-insertable Power ON 22 Festo Didactic

23 Dimensions (H x W x D) 112 x 330 x 300 mm (4.4 x 13.0 x 11.8 in) 3.5 kg (7.7 lb) Direct FM Multiplex Generator the signal-to-noise ratio at the receiver. The Direct FM Multiplex Generator offers practical experience in the techniques of direct FM modulation. Multiplexed audio input signals form FM stereo modulation of a carrier in the commercial FM frequency band of 88 to 108 MHz. Switchable 75-μs preemphasis can be added to the left and right stereo signal inputs to increase A third audio output allows modulation of a VCO around a center frequency of 67 khz (used for subsidiary communications authorization, SCA, service in some countries). The VCO frequency can also be varied between 25 and 100 khz. Each multiplexed signal forming the baseband signal (L + R, L - R, 19 khz pilot, and SCA signals) can be switched on or off. A separate control allows level adjustment of each signal, so that students can observe the effect of signal amplitude on carrier deviation. An auxiliary input permits direct injection of a signal into the baseband. Observation of the group of signals that make up the baseband signal is possible via the MUX output. Through the front panel controls, the phase, maximum carrier deviation, and the RF amplification level of the 19 khz pilot signal can be varied. An FM generator frequency control and a switch to invert the L + R and L - R signals are located inside the module. Power Requirement L R Audio Inputs Bandwidth Impedance Level SCA Input Bandwidth Subcarrier Frequency Range Baseband Section Pre-emphasis AUX Input Impedance Controls +25 V ma - DC; -25 V ma - DC 50 Hz to 15 khz 10 kω 500 mv p-p (for calibrated deviation) 300 Hz to 3 khz 25 to 100 khz, with calibrated position at 67 khz 75 µs, Switch-controlled 25 kω Phase Adjust Range -180 to 0 Intermediate Output RF Section Output Frequency Output Impedance Output Power Controls Deviation Range Faults Test Points 34 Indicator Dimensions (H x W x D) Pilot phase adjust, level adjust, cut-off switches (for L+R, L-R, SCA, and pilot) Baseband 88 to 108 MHz (internally adjusted) 50 Ω Less than 100 mw (no permit required) Deviation, RF gain 5 to 100 khz, with calibrated position at 75 khz (all inputs 0.5 V p-p and LEVEL controls at CAL) 12, switch-insertable Power ON 162 x 330 x 300 mm (6.4 x 13.0 x 11.8 in) Festo Didactic 23

24 4.2 kg (9.2 lb) Indirect FM/PM Generator The Indirect FM/PM Generator is designed to teach the techniques used in indirect generation of FM and phase-modulated (PM) signals. With the indirect method, either a PM or an FM signal can be produced using a phase modulator. Frequency modulation occurs when the audio signal is passed through an integrator before being sent to the phase modulator. Narrowband frequency modulation (NBFM), wideband frequency modulation (WBFM), and phase modulation can all be performed with the indirect FM/PM Generator. The frequency of the generated RF signal is 10.7 MHz for NBFM and PM, and MHz in WBFM. The PM signal is generated by the Armstrong Method. Gain controls are provided to adjust the level of the PM, NBFM, and WBFM signals at their respective outputs. Modulation is carried out at the frequency of the base oscillator. BNC connectors, at both the mixer and amplifier outputs, provide a means to observe the modulated signals before they are multiplied and output at MHz. Power Requirement Audio Input Bandwidth Impedance Level PM/NBFM Section Output Frequency Output Impedance Output Power Deviation (NBFM) Controls Intermediate Outputs WBFM Section Output Frequency Output Impedance Output Power Deviation Control Faults Test Points 20 Indicator Dimensions (H x W x D) +25 V ma - DC; +11 V ma - DC; -25 V - 75 ma - DC 300 Hz to 3 khz 10 kω 500 mv p-p (for calibrated deviation) 10.7 MHz 50 Ω Less than 100 mw (no permit required) 5 khz (for 500 mv p-p input signal) PM/FM mode switch, RF gain Mixer, summing amplifier MHz 50 Ω Less than 100 mw (no permit required) 75 khz (for 500 mv p-p input signal) RF gain 8, switch-insertable Power ON 112 x 330 x 300 mm (4.4 x 13.0 x 11.8 in) 3.6 kg (7.9 lb) 24 Festo Didactic

25 FM/PM Receiver The FM/PM Receiver offers training in multiplex and wideband FM (covering commercial broadcast techniques), narrowband FM (widely used in commercial and military communications systems), and PM reception. PM reception is used in such applications as satellite communications, data communications, over narrowband communications systems, telephone lines, microwave communications lines and links. When the FM/PM Receiver is connected with the Direct FM Multiplex Generator, a complete commercial FM system is established. Students can readily see the effects of stereo signal generation, multiplexing techniques, and modulation. When the FM/PM Receiver is connected to the Indirect FM/PM Generator, a narrowband FM communications link is established, allowing the student to explore the generation and reception of narrowband FM and PM signals. RF inputs to the receiver are between 88 and 108 MHz for stereo and wideband FM, and 10.7 MHz for narrowband FM and PM. A demodulated audio signal is available at the NBFM audio output when a signal is injected at the RF input. When the output of the crystal discriminator is connected to the input of the integrator, a demodulated audio signal is available at the PM audio output. The WBFM section is equipped with two 50 Ω RF inputs, a balanced 300 Ω RF input for an external antenna connection, and an RF tuning knob which allows tuning across the 88- to 108-MHz band. A 3-LED tuning indicator and a 10-LED bar graph display (indicating received signal level) facilitate accurate tuning. The presence of the 19 khz pilot signal illuminates an LED also. A 2½ digit display can show the frequency deviation of the received WBFM or NBFM signals. These meters are often used on modern communications receivers. Receiver outputs for FM left and right stereophonic channels, monophonic FM, NBFM, and PM are provided, as well as an SCA channel audio output, often used for background music programming. Power Requirements Power Requirements WBFM Section Input Impedance +25 V dc ma +11 V dc ma -25 V dc ma 2 inputs at 50 Ω, 1 input at 300 Ω (balanced) 50 Ω Input Sensitivity 55 µv (typical for both inputs for 10 db S/N at baseband output) 300 kω Input Sensitivity 15 µv ( typical for 10 db S/N at baseband output) AUX IF Input Impedance Control RF Tuning Range Intermediate Outputs Indicator PM/NBFM Section Input Frequency Input Impedance Input Level Sensitivity Audio Outputs 50 Ω RF tuning 88 to 108 MHz IF (10.7 MHz), baseband Deviation (switchable between WBFM and NBFM) 10.7 MHz 2 inputs at 50 Ω 3 mv (typical for 100 mv p-p at NBFM audio output) Festo Didactic 25

26 L, R, L + R Bandwidth 50 Hz to 15 khz SCA, NBFM, PM Bandwidth Impedance Fault-Insertion Switches 12 Test Points 35 Indicators Dimensions (H x W x D) 200 Hz to 3 khz 1 kω (all outputs) Center tuning, signal level, pilot (19 khz), deviation display (2½ digits), Power ON 162 x 330 x 300 mm (6.4 x 13.0 x 11.8 in) 4.7 kg (10.3 lb) Optional Equipment Description Dual Trace Oscilloscope (Optional) The Dual Trace Oscilloscope is an economical and highly reliable solidstate instrument, ideal for generalpurpose use in laboratory and training applications. Students can measure phase difference between waveforms using the X-Y operation mode, and video signals can be measured quickly with the special TV sync separation circuit. The Dual Trace Oscilloscope includes CH 1, CH 2, CHOP, and ALT display modes. An operating instruction manual, one fuse, one line cord, and two low-capacitance probes are provided with the oscilloscope. Features & Benefits 15 cm (6 inch) width, high luminance CRT with internal graticule, 8 x 10 divisions Wide dynamic range even at high frequencies of 3 db Fast rise time with low overshoot Flat frequency response up to half of 3 db frequency Alternate and chopping display Polarity inversion and algebraic sum of CH1 and CH2 Maximum sweep rates of 20 ns/div. Variable scale illumination Delayed sweep function with minimum delay time jitter of 1/20,000 or less Jitterless and superb trigger sensitivity TV sync separation and hold-off circuit useful for video signal observation Brightness modulation available with Z-axis input Low drift with compensation circuitry Signal delay with delay line useful for observation of signal leading edge X-Y phase difference measurement up to 50 khz Power Requirements Current Service Installation CRT Display 0.25 A Standard single-phase ac outlet 26 Festo Didactic

27 Type cm (6 in) rectangular, internal graticule, scale illumination Effective Area 8 x 10 div (1 div = 1 cm) Acceleration Potential 12 kv Vertical Deflection Sensitivity 5 mv/div to 5 V/div in 10 calibrated steps ±3% 1 mv/div to 1 V/div ±5% when using x5 magnifier Uncalibrated continuous control between steps 1:<2.5 Bandwidth DC to 40 MHz (-3 db); dc to 7 MHz (-3 db) when using x5 magnifier Rise Time Less than 8.8 ns Maximum Input 300 V (dc + ac peak) or 500 V p-p ac at 1 khz or less Input Coupling AC, GND, DC Input Impedance 1 meg in parallel with 25 pf Operating Modes CH1, CH2 (INVERT), ADD, DUAL (CHOP: Time/div sw 0.2 s - 5 ms; ALT: Time/div sw 2 ms - 0.2µs) X-Y Operation CH1: X-axis, CH2: Y-axis Horizontal Deflection Display A, A int B, B, B triggered, X-Y Time Base A 0.2 µs/div to 0.2 s/div in 19 calibrated steps ±3% uncalibrated continuous control between steps at least 1:<2.5 Time Base B 0.2 µs/div to 20 µs/div in 7 calibrated steps ±3% Trigger Modes Auto, Norm, TV-V, TV-H Coupling AC Sources CH 1, CH 2, LINE, EXT Sensitivity (Internal Source) 0.5 div (20 Hz to 2 MHz), 1.5 div (2 MHz to 40 MHz) Sensitivity (External Source) 200 mv (20 Hz to 2 MHz), 800 mv (2 MHz to 20 MHz) Slope + or - TV Sync Polarity: TV (-) Calibrator 1 khz, square wave, 0.5 ±3%, duty cycle: 50% Accessories Power cable, fuse, operation manual, 2 probes Dimensions (H x W x D) 140 x 320 x 430 mm (5.5 x 12.6 x 16.9 in) 5.7 kg (12.57 lb) Personal Computer (Optional) A The Personal Computer consists of a desktop computer running under Windows 10. A monitor, keyboard, and mouse are included. Power Requirements Current Service Installation 1.05 A Standard single-phase ac outlet Festo Didactic 27

28 Dust Cover for Model 8080 (Optional) The Dust Cover for Model 8080 is a flexible fabric cover specially designed to protect the equipment in the Analog Communications Training System, Model 8080, against the accumulation of dust during extended storage periods. 28 Festo Didactic