Limited quantity of refurbished Model 500 Telephone Test Systems available. Contact Microtronix or your local Microtronix representative for information. We continue to provide Technical Support, Test Programming, Calibration, Upgrade and Repair Services to Model 500.



The Model 500 Telephone Test System is a full featured testing solution developed with flexibility and affordability in mind. Its versatile, modular design allows us to configure a system to suit your testing needs. The rugged design is built for harsh environments.

Model 500

The Model 500 Telephone Test System consists of the Controller Unit, the Measurement Unit, the Central Office Simulator with Modules Unit, and the Acoustic Fixture.

Telephone Test System Features

  • Fully Tests Acoustic & Electrical Properties
  • Standards Compliant Artificial Head
  • Test Limits Easily Programmed
  • High Speed, Accurate, Repeatable Readings
  • GPIB Control Available
  • Programmable Caller ID testing
  • Programmable Central Office with changeable modules for flexibility
  • Programmable Length Transmission Lines
  • Generates DTMF signals, Call Progress Tones, and CAS Tones
  • Detailed test results can be displayed on the Controller Unit's monitor or sent to a printer
  • Up to 48 different Test Programs containing limits and testing sequences can be stored in non-volatile RAM.
  • Rugged steel construction

Available Options

Microtronix provides a wide range of Hardware Options and Software for the Model 500 Test System. Below are listed some of the more popular applications.

Country Kits A Microtronix Country Kit is the result of hours of study by our staff to provide you with a solution for testing to published standards in countries around the world. We combine all the C.O. modules required and comprehensive Test Program Software with a manual describing the way we perform the test, what it means and where we got the information right down to the paragraph and figure numbers of the country specification document. It doesn't get any easier.


Graph ManagerGraph Manager Graph manager is a Windows program that plots the Model 500 test results on your PC. It connects with an RS232 cable and provides customizable graphing screens that can be printed or saved as files. Line colours and styles are selectable and the graph positions on the screen can be adjusted for each Test Program and each Test Step.

Summary Collector
The Summary Collector Program for Windows automatically collects and stores the Model 500 Summary Reports to your PC's disk drive or local area network. Connected by an RS232 cable Summary Collector can organize the test results for you. For example it can place all failed phone reports in a separate network folder for fast access by rework personnel.

Summary Collector

Click to Enlarge

File names can be automatically assigned by summary collector (incrementing numbers) or you can use a bar code reader and use the telephone bar code as the file name. File names can also include a prefix for your identification purposes and Summary Collector can also place a suffix letter on the end of the file name to indicate PASS, FAIL or INCOMPLETE.

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Available Tests

  • Transmission Tests (Response and Loudness)
  • Return Loss
  • DTMF Dial
  • Pulse (Loop Disconnect) Dial
  • Ringer/Alerter
  • Caller ID Features
  • Off-Hook DC Voltage and Current
  • AC Impedance
  • Hookswitch Flash
  • Hookswitch Sequence
  • Earth Loop Recall
  • Receiver Varistor
  • Bell Tap
  • Modem Test for telephones with built-in modems

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System Hardware

The Model 500 Units fit standard 19" racks and are stackable. These separate units are connected together using a Microtronix Analog Bus cable and a Digital Bus cable.

Controller UnitController Unit

  • Instant start up from reset or power on.
  • Instant Test Program starts from memory.
  • No disk drives for maximum reliability in harsh environments
  • Rugged power supply keeps working under a wide range of input voltage
  • Built-in 9" monochrome screen for displaying test instructions, messages, and detailed results
  • 27 button keypad
  • Microtronix L4 System Firmware in FLASH memory provides test sequence control, test execution and operator user interface
  • Parallel printer port
  • Multiple RS-232 ports for connection to Graph Manager and Summary Collector

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Measurement UnitMeasurement Unit

  • Two independent Voltmeters with Tracking bandpass filters for discrimination from room noise
  • Optional A-weighting, C-message, Psophometric filters and distortion filters.
  • Interface to Acoustic Fixture with power amplifier for artificial mouth.
  • Internal loudspeaker
  • Oscilloscope output
  • Programmable Oscillator

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Central Office SimulatorCentral Office Simulator

  • Programmable DC Power Supply
  • Programmable Ringer Signal Generator
  • Tip-Ring Interface
  • DC Feed Inductors
  • Loop Current indicator light

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The Modules Unit (seen on top) contains the plug-in C.O. configuration modules and Transmission Lines. ( Country Kits include all the correct modules for testing to a specific country's standard.)

Module Types Contained in a Modules Unit:

  • Programmable Length Transmission Lines
  • Source/Termination Impedance Modules
  • Programmable DC Feed module
  • DC Feed Capacitor Modules
  • Ringer Resistance Modules
  • Bell Tap Modules
  • Parallel Terminations
  • Custom Modules and special Feed Bridges

Modules Expansion Units

The Model 500 System can accommodate as many as seven Modules Units. This allows a system to contain enough feed circuitry to allow as many as ten to fifteen country kit applications to be ready a the touch of a button.

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Acoustic Fixture

  • Rugged and simple construction for heavy production use
  • Quick handset clamping
  • Artificial Mouth output can be regulated either by using the built-in microphone for real-time feedback, or by applying predetermined voltages saved in a look up table during calibration.
  • Multiple position Artificial Mouth can be correctly configured for testing in accordance with ITU-T or OREM position.
  • Can be equipped with IEC-318 ear, ANSI 6cc or NBS9a artificial ears
  • Spring loaded Acoustic Coupler travels on linear bearings to accommodate handset variations
  • Molded Handset Locating Rings guarantee consistent handset positioning

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  • System Firmware stored in FLASH memory
  • Microtronix customers can download System Firmware updates from the secure Microtronix Online ftp Server to their PCs, then download into the Controller Unit's FLASH memory
  • A powerful Test Program Command Line language allows customers to create virtually any type of customized test
  • A statistical summary of the total handsets tested, Percentage Yield, and the specific tests which failed are tallied for each type of handset and stored in battery backed non-volatile memory.