GSi 61 User Manual

™

GSI 61

USER MANUAL

Setting The Clinical Standard www.grason-stadler.com

Grason-Stadler, 7625 Golden Triangle Drive, Suite F, Eden Prairie MN 55344

800-700-2282 • 952-278-4402 • fax [phone] • e-mail [e-mail]

Part Number 1761-0100 Rev B

Title:

GSI 61 User Manual

Copyright © 2011 Grason-Stadler Inc

reproduced or transmitted in any form or by any means without the prior written permission of
Grason-Stadler Inc. The information in this publication is proprietary to Grason-Stadler.

Compliance

The CE 0344
Stadler is an ISO 13485 certified corporation.

European Authority Representative

Grason-Stadler
Kongebakken 9
2765 Smørum
Denmark

0344

mark identifies compliance with the Medical Device Directive 93/42/EEC. Grason-

.

All rights reserved. No part of this publication may

be

1761-0100 Rev. B i

Warnings, Cautions and Errors

Warning!
Accessory equipment

connected to the analog
and digital interfaces
must be

certified to the
respective IEC
standards (IEC950 for
data processing or IEC

60601-1 for medical
equipment)
Furthermore, all
configurations s hall
comply

with the system
standard IEC 60601-1-1
Everyone who connects
additional

equipment to the signal
input or signal output
port configures a
medical system,

and is therefore
responsible that the
system complies with

Cautions

the requirements of
the system standard

IEC60601-1-1
doubt, consult the
technical service

department or a local
representative.

.

.

If in

The GSI 61 Clinical Audiometer is designed to be used with a hospital grade outlet. Injury to
personnel or damage to equipment can result w hen a three-prong or two-prong adaptor is
connected between the GSI 61 power plug and an AC outlet or extension cord.

Audiometers which bear the Underwriters Laboratories, Inc
with accessories that have the proper electrical compatibility and are listed as meeting the
requirements of the UL Medical and Dental Equipment Standard. Connecti on of accessories
not meeting these requirements may result in electrical leakage currents in excess of those
allowed by the standard and present a potential electrical shock hazard to the person being
tested.

This warning icon found on the back of the LCD panel indicates dangerous voltage within the

panel. Access to the LCD pa nel is lim ited to authorized Grason-Sta dler
service representatives.

.

When testing with the High Frequency earphones, do not allow the
presentation of the signal at the maximum dB HL to exceed 10 m inutes.
The buildup of increased temperature can cause harm to the earphones.

This caution label refers the user to the accompanying literature and
manuals.

This icon indicates that the GSI 61 is in compliance with Class 1,
T ype B requirements of IEC 601-1.

.

label should be interconnected

Cautions

ii

The following is the list of status messages which will occur
with operation of the GSI 61 Audiomet er. These messages will
be displayed in one of the bottom three message areas.

1761-0100 Rev. B

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Status Messages

Using Default Data Indicates that the selected transducer and stimulus are not

Erasing Data Indicates that the GSI 61 is clearing stored test information.
Saving Data Indicates that the test information is being saved into memory.
No T est Data Stored Indicates that there is no test data available to be erased or

Check Hi-Freq Cables Indicates that the High Frequency function is enabled but the

Invalid Selection Indicates that an incorrect selection, such as incompatible

Not Available Indicates an uninstalled option has been selected.
No T est Data Stored Indicates that there is no data available for printing, although

Data T ransfer Indicates that data has been processed either by the printer or

Check Printer A check is done to see if the printer is connected and ready to

Printing This is an informational message which is displayed while

No Printer Response If communications problems occur during the course of printing,

calibrated to standard specified (ANSI/ISO) levels.

printed.

cables plugged into the L&R phone jacks are not the GSI­specified type.

transducers, has been made.

the Print Audiogram button has been pressed.

by a remote computer .

receive data by checking the hardware flow control line. If
printer is not ready this message will be flashed.

outputting data to the printer. It appears on th e lower right
section of the LCD.

this error message will be flashed.

Communications Error Messages

The following communication errors may occur during data transmission through the RS 232
communications:

Comm error: par ity Check GSI 61 and PC parity settings.
Comm error: framing Check GSI 61 and PC selections for number of stop

Comm error: overrun See ‘framing’.
Comm error: multiple Check parity, baud rate, number of stop bit s and

Comm er ror: spurious Soft error. Should not be repeata ble; if so, problem

Comm error: break See ‘spurious’.

If the word “Help” followed by an error code is displaye d, note the Help Code number . See the
GSI 61 Service Manual (1761-0110) for detailed descriptions of these. Turn off the power to
the GSI61 and wait 30 seconds. Restart the instrument. Often the error will be cleared by this
action. If the error persists, contact an authorized Grason-Stadler service representative.

bits and number of bits per comm and.

byte size on GSI 61.

could be anywhere in GSI 61 digital circuits or PC’ s
communication circuits.

1761-0100 Rev. B

iii

Warranty

We, Grason-Stadler, warrant that this product is free from defects in material and
workmanship and, when properly installed and used, will perform in accordance with
applicable specifications. If within one year after original shipment, it is found not to
meet this standard, it will be repaired, or at our option, replaced at no charge except
for transportation costs, when returned to an authorized Grason-Stadler facility. If
field service is requested, there will be no charge for labor or material; however,
there will be a charge for travel expense at the service center’s current rate.

Note: Changes in the product not approved in writing by Grason-Stadler shall void
this warranty. Grason-Stadler shall not be responsible for any indirect, special or
consequential damages, even if notice has been given in advance of the possibility of
such damages.

THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR
IMPLIED, INCLUDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

1761-0100 Rev. B

iv

Specifications

Standards

Pure Tone - Channel
1 and Channel 2

The GSI®61 Clinical Audiometer meets or exceeds the following st andards: ANSI S3.6-198 9;
ANSI S3.43-1992; IEC 645-1 (1992); IEC 645-2 (1993); ISO 389; UL 2601-1 Medical Electrical
Equipment; IEC 601-1 Medical Electrical Equipment and CSA C22.2, No. 601.1-M90
Electromedical Equipment.

The CE mark on this product indicates it conforms with the provisions noted in the 93/42/EEC
Medical Devices Directive.

CE Mark per Medical Device Directive (93/42/EEC)

0344

European Authority Representative
Grason-Stadler A/S
Kongebakken 9
2765 Smørum
Denmark

Frequency Range

Air Conduction 125 Hz to 12000 Hz
High Frequency (optional) 8 k Hz to 20 k Hz
Bone Conduction 250 H z to 800 0 Hz
Sound Field (optional) 125 Hz to 12,000 Hz (125 Hz to 16,000 Hz

only with High Frequency option, 1761-9630, enabled)
Paired Insert (optional) 125 Hz to 8000 Hz
Single Insert (optional) 250 Hz to 6 000 Hz
Accuracy ± 1 %
T otal Harmonic Distortion £2% (earphones and paired insert phones*)

£5% (bone vibrator)

Intensity Range **

Air Conduction: -10 dB HL to 120 dB HL
High Frequency:* -20 dB HL to 100 dB HL (with Sennheiser HDA 200

Phones)
Bone Conduction:

Mastoid -10 dB HL to 80 dB HL

Forehead -10 dB HL to 70 dB HL
Sound Field:* -10 dB H L to 96 dB H L
Paired Inserts:* -10 dB HL to 110 dB HL
Single Insert:* -10 dB HL to 110 dB HL

Masking Intensity Range (Calibrated in effective masking)

Narrow Band N oise: Maximum dB HL is 15 dB below tone

White Noise: Maximum dB HL is 30 dB below tone

* Optional accessories
** The maximum HL values are applicable to the middle frequencies only.

GSI® 61 is a registered trademark o f Grason-Stadler. All rights reserved.

1761-0100 Rev. B

v

Grason-

S

tadler GSI® 61 CLINICAL

Speech Channel 1 and
Channel 2

Microphone: For live voice testing and comm unications
External A and External B: Accepts recorded speech material from external

stereo tape cassette or CD player

Intensity Range:

Air Conduction: -10 dB HL to 105 dB HL
Bone Conduction:

Mastoid -10 dB HL to 65 dB HL

Forehead -10 dB HL to 55 dB HL
Sound Field:*** -10 d B HL to 90 d B HL
Paired Inserts:*** -10 dB HL t o 95 dB HL
Single Insert:*** -10 dB H L to 95 dB H L

Masking Intensity Range

Speech Noise:

Air Conduction (TDH 50P and Ins ert Phones *) and Bone

Conduction

Maximum dB HL are the same as the speech type signals.

Sound Field: -10 dB HL to 80 dB HL
White Noise: Equal to Speech Noise

*** Optional Accessories

Steady: Tone continuously present.
Pulsed: T one pulsed 200 mSec ON, 200 msec OF F .
FM : Tone modulated ± 5% of cente r frequency at a rate of 5 Hz.

Signal Format

Special Test
Capabilities

Communications and
Monitoring

Dimensions and
Weight

ALT : T one alternating between Channel 1 an d Channel 2: Cha nnel

1 is 400 mSec ON, 400 mSec OFF followed by Channel 2, 400 mSec
ON, 400 mSec OFF .

SISI: An intensity increment is added to a tone in the selected channel for

200 mSec, every 5 seconds. The HL increments are available in 1, 2
or 5 dB steps.

High Frequency: T one testing in the freque ncy range of 8 kHz to 20 kHz

using High Frequency phones or Sound Field.
The frequencies available for testing are: 8 kHz, 9 kHz,
10 kHz, 11.2 kHz, 12.5 kHz, 14 kHz, 16 kHz, 18 kHz
and 20 kHz (Optional).

Talk Forward: Permits the tester to speak through the test microphone into the

selected transducer at the intensity level set by the front panel
controls.

Talk Back: Allows the tester to listen to comments from the subject in the

testing booth.

Monitor: Th e monitor h ead set or monito r speak er can be u sed b y the tester

to listen to Channel 1, Channel 2 and/or T a lk Back signals.

W x D x H : 20 inche s x 15 inches x 12.6 inches (LCD raised)

50 cm x 39 cm x 32 cm

Height with LCD lowered - 6 inches (15 cm)
Weight: 19 pounds 8.7 kg
Shipping Weight: 30 pounds 13 .6 kg

vi

1761-0100 Rev. B

Instrument Specifications

Power Consumption
Accessories Supplied

Optional Accessories

90 Watts

Test Headset (Matched set TDH-50P) -------------------------------------------------- 8000-0063
Bone Vibrator (B71) ----------------------------------------------------------------------- 8000-0130
Subject Response Handswitch ----------------------------------------------------------- 7874-0156
Test Microphone/Monitor Headset with coiled cord ---------------------------------- 1761-9623
Talk Back Microphone -------------------------------------------------------------------- 8000-003 9
Patch Cords, 6 ft. Grey (4/each) ------------ ---------------------------------------------- 4204-0505
Power Cord --------------------------------------------------------- (Country and voltage specific)
Instruction Manual - English -------------- -- -- -------------------------- -- --------------- 1761-0100
Instruction Manual - Spanish ------------ -- -- -------------------------- -- ----------------- 1761-0104
GSI Suite Audiometic Data Management Software ---------------------- ------------- 1010-9600

CD Player ----------------------------------------------------------------------------------- 1761-9621
Stereo Tape Cassette -------------------------------- -------------------------------------- 1761-9622

Speakers, Basic (90 dB) with cables (125 - 16 kHz) ------------------------------------- 1761-9630
Speakers, High Performance (96 dB) with cables (125 - 8 kHz) ----------------------- 1761-9635

Booster Amplifier (220-240V) with cables,
for use with the High Performance Speakers only----------------------------------- 1761-9636
Booster Amplifier (100-120V) with cables,
for use with the High Performance Speakers only----------------------------------- 1761-9637

Sound Field System, High Performance (102 dB, 220-240V , 125 - 8 kHz)
includes High Performance Speakers and Booster Amp ---------------------------- 1761-9638
Sound Field System, High Performance (102 dB, 100-120V , 125 - 8 kHz)
includes High Performance Speakers and Booster Amp ---------------------------- 1761-9639

Paired Insert Phones (E•A•R TONE
E•A•R TONE
E•A•R TONE

TM

Replaceme nt Foam Eartips , Std----------------------------------------- 1700-9604

TM

Replac ement Foa m Eartips , Small -------------------------------------- 1700-9605

TM

3A) ----------------------------------------------- 1700-9606

Single Insert Phone (470) -------------------------------- ---------------- ---------------- - 1700-9609

High Frequency Headphones w/booth cables ----------------------------------------- 1761-9602
High Frequency Cables (to sound booth) --------------------------- ------------------- 1761-9603
(If using High Freq Headphones, these cables are required to connect to the GSI 61)

High Frequency Headphones w/cables to GSI 61 ---- ---- ---- ---- ---- ---- ---- ---- ---- - 1761-96 04
High Frequency Cables (to GSI 61) ---------------------- -------------------- ------------ 1761-9605
(If using High Freq Headphones, these cables are required to connect to the GSI 61)
Remote RS 232/Pr inter Inter face -------------------------- -------------------------- ------ 1761-9680
Printer, Color (North Am erica only) ------------------------------------------------------ 1761-9610
Service Manual ----------------------------------------------------------------------------- 1761-0110
Audiocups ---------------------------------------------------------------------------------- 8000-0155
OtoAccess (Network Software for GSI Suite) --------------------------------------- 1015-9600

1761-0100 Rev. B

vii

E

F

G

Grason-Stadler GSI® 61 CLINICAL

Catalog Listings

GSI 61 Clinical AudiometerwithoutRemote

English ---------------------------------------------------------------------------------- 1761-9700-XX
French ------- -------------------------- -------------------------------------------------- 1761-9700-XX
German --------------------------------------------- ------------------------ ------------- 1761-9700-XX

Italian -----------------------------------------------------------------------------------1761-9700-XXI

Spanish --------------------------------------------------------------------------------- 1761-9700-XXS

GSI 61 Clinical Audiometer with USB Remote

English ---------------------- ------------------------------------------------ -- -- -- ---- 1761-9780-XXE
French --------------------------------------------------------------------------------- 1761-9780-XXF
German ----------------------------------------- --------------------------------------- 1761-9780-XXG

Italian -----------------------------------------------------------------------------------1761-9780-XXI

Spanish--------------------------------------------------------------------------------- 1761-9780-XXS

Notes -XX refers to the voltage and plug requirements for the country of operation.

viii

1761-0100 Rev. B

Electromagnetic Compatibility (EMC)

1761-0100 Rev. B

ix

Table of Contents

Preface

Chapter 1

Introduction

Chapter 2

Installation

Title---------------------------------------------------------------------------------------------------------i

Warnings, Cautions and Errors- -----------------------------------------------------------------------ii

Warranty -------------------- -- -------------------------- ------------------------------------------------iv
Specifications ------------------------------------------------ -- -------------------------- -- -- -----------v

Standards -------------------------------------------------------------------------------------------v
Pure Tone - Channel 1 and Channel 2 --- ------------------------------------------------------v

Speech Channel 1 and Channel 2 --------- -----------------------------------------------------vi
Signal Format ---------------------- -- -------------------------- -- -------------------------- -------vi
Special Test Capabilities ------------------------------------------------------------------------vi
Communications and Monitoring --- --------------------------------------------------- --------vi

Dimensions and Weight------------------------------ ------------------------ --------------------vi
Power Consumption ---------- -------------------------------------------------------------------vii
Accessories Supplied----------------------------------------------------------------------------vii
Optional Accessories ----------------------------------------------------------------------------vii
Catalog Listings ---------------------------------------------------------------------------------viii

Electromagnetic Compatibility (EMC)-------------------------------------------------------------ix

Introduction ------------------ -- -- -------------------------------------------------- ------------------- 1-1

External Inspection --------------------------------------------------------------------------------- 2-1
Unpacking ------------------------------------------------------------------------------------------- 2-1
Accessories Supplied ------------------------------------------------------------------------------ 2-1
Connectors, Controls and Indicators ------------------------------------------------------------- 2-2

Rear Panel -------------------------------------------------------------------------------------------- 2-2

Left Side Panel--------------------------------------------------------------------------------------- 2-4
Right Side Panel ------------------------------------------------------------------------------------- 2- 4
Front Panel Controls -------------------------------------------------------------------------------- 2-5

V ali d Stimuli Combi nations --------------------------------------------------------------------2-8

V alid T ransducer Combinations --------------------------------------------------------------2-8

Displays ----------------------------------------------------------------------------------------2-14

Test Microphone/Monitor Headset ----- ------------------- ------------------ ------------------ - 2-17

Optional Accessories ------------------------------------------------------------------------------2-18

Hearing Level And Freque ncy Limits------ ---------------- -------------- -------------- ----------2 - 2 4
Initial Installation ----------------------------------------------------------------------------------2-26

Single Room Environment ------------------------------------------------------- ------------2-27
Two Room Installation ------------------------ ------------------------------ ------------------2-27
Loudspeaker Installation ---------------------------- -----------------------------------------2-29

1761-0100 Rev. B

Contents-1

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Grason-Stadler GSI® 61 CLINICAL AUDIOMETERGrason-Stadler GSI® 61 CLINICAL AUDIOMETER

Chapter 3

Operation

Preliminary Checks--------------------------------------------------------------------------------- 3-1

Patient Instructions ----------------------- ---------- -------- -------- ---------- -------- ---------- ---- 3-2

Placement of the Earphones ---------- --------------------------------------------------------3-2
Placement of the Insert Phone ---------------- ------ ------ ------ ------ ------ ------ ------ ------ 3-2
Placement of the Bone Vibrator ---------------------------------------------------------------3-2

Routine Test Procedures ------------- ------------------------ ------------------------------------- 3-3

Threshold Determination (Pure Tone): Modified Hughson-Westlake ------ -- -- -- -- ----3-3

Spondaic Speech Testing, Speech Reception Threshold (SRT) --------------------------3-4
Speech Discrimination (PB Words) -----------------------------------------------------------3-4

Chapter 4

Special Test
Procedures

Alternate Binaural Loudness B alance (ABLB) or Fowler T est -------------------------- ------ 4-2
Monaural Loudness Balance (MLB) Test -------------------------------------------------------- 4-3
Short-Increment Sensitivity Index (SISI) --------------------------------------------------------- 4-4

Modifications to the SISI test ---------------------------------------------------------------- 4-4

High Frequency Testing (Optional)------------------------------------------------------------- -- 4-5

High Frequency Testing: Setup Diagrams ---------------------------------------------------4-5
Sensorineural Acuity Level (SAL) T est ---------------------------------------------------------- 4-6
Hearing Aid Evaluation -------------- -------------------------- -- -------------------------- -- ------ 4-6
Tone Decay Test ------------------------------------------------------------------------------------ 4-8

Lombard or Voice-Refl ex T est ---------------------------------------------------------------------- 4-8
Delayed Auditory Feedback (DAF)--------------------------------------------------------------- 4-9

Staggered Spondaic Word Test (SSW)---------------- ------------------------------------------4-10

Doerfler-Stewart T est ------------------------------------ ---------------------- --------------------4-1 1

Modified Doerfler-Stewart Test--------------------------------------------------------------4-11

Pure Tone Stenger Test ---------------------------------------------------------------------------4-12

Chapter 5

Routine
Maintenance

Biological Calibration Che ck ----------------------------------------------------------------------- 5-1
Periodic Checks ------------------------------ ------------ ------------ ------------ ------------ ------- 5-1
Calibration Reference Levels ---------------------------------------------------------------------- 5-3

Line Voltage Brownout and Interruptions ---------- ---------------- ---------------- -------------- 5-6
The Message “CAL” -------------------------------------------------------------------------------- 5-6
The Message “Help” -------------------------------------------------------------------------------- 5-6

Contents-2

1761-0100 Rev. B

T able of Content s

y

Chapter 6

Remote Options

RS 232 Configuration --------------------------------------------------------------------------------6-1
USB Overview ---------------------------------------------------------------------------------------- 6-3
Driver Installation and System Setup -------------------------------- ------------------------------6-4

GSI Suite -------------------------------------------------------------- ------------------------ ---------6-4

Data Flow Control Operation ------------------ ---------------- ------------------ ---------------- --- 6-5

Hardwa re Flow Contro l -------------------------------------- -------------------------- -------- 6-5
Softwa re Flow Co ntrol -------------------------------------- ------------------------ ----------- 6-5

Cable Connections---------------------------- ------------------------------------------------- 6-5

Data Transfer ----------------------------------------------------------------------------------------- 6-6

Record and Field Formatting ------------------------------------------------------------------ 6-6

Checksums -------------------------------------------------------------------------------------- 6-6

Remote Input Operation----------------------------------------------------------------------------- 6-7

Input Record Type -------------------------------------------- ---------------------------------- 6-7

Input Record Type 1 to 4 ---------------------------------------------------------------------- 6-7

Input Record Type 5 - Pushbutton Code Record ------------------------------------------- 6-7
T ype 6- Set Test Frequency Record --------------------------------------------------------- 6-11
T ype 7 - Set HL Record ------------ ------------------------ ---------------------- ------------- 6-12

Remote Output Operation---------------------------------------------------------------------------6-13

T ype 1- GSI 16 Compatible Short Data Record--------------------------------------------- - 6-13

T ype 4 - Error Record -------------------------------------------------------------------------- 6-16
Type 5 - GSI 61 Short Data Record ----------------------------------------------------------6-16
T ype 6 - Test Battery Data Record ------------------------------ ---------- ---------- ---------6 -18

Rec ord Pre fix ------------------------ ------------------------------------------ -----------------6-18

Left Ear T est Data - Pure T one ---------------------------------------------------------------6-18

Speech Test --------------------- ------------ -------------- -------------- ------------ -----------6-20
SISI Test ------------------------ -------------- ------------ -------------- -------------- ----------6-2 0

Alter nate (AB LB) ----------------------- ---------------------------------- ---------------------6-22

Right Ear T est Data ----------------------------------------------------------------------------6-23

Record Term inator ----------------------------------------------------------------------------6-23

T ype 7 - Instru ment Type --------- ------ ------ ------ ------ ------ ------ ---- ------ ------ ------ --6-2 3

Remote Output Operation continued ----------- --------------------------------------------------6-24

T ype 8 - Unit Configuration Record ---------------------------------------------------------6-24

Appendix

Bibliography

Regulatory
S

mbols

Test Words ---------------------------------------------------------------------------------------- A1-1
Part One -------------------------------------------------------------------------------------------- A1-1
Part Two -------------------------------------------------------------------------------------------- A1 -1

Bibliography ------------ ---------------------- ---------------------- ------------------------ ---------- B-1
Bibliography for Test Procedures ------------ -------------- -------------- ---------------- --------- B-2

Regulatory Symbols------------------------------------------------------------------------------------C-1

1761-0100 Rev. B

Contents-3

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Blank page.

Contents-4

1761-0100 Rev. B

n

Chapter 1

Introduction

for the test sequence. The Tracking pushbutton allows the operator to synchronize intensity
changes on Channel 2 with those m ade on Channel 1.

All data, including the instrument selected parameters, are displayed on an articulating Liqui d
Crystal Display (LCD). Pure tone test results are presented in either a “status” or an audiogram
format. The status format clearly shows all test conditions and permits the calibration check
of input from the microphone or from recorded test materials. The audiogra m format for pure
tone testing displays the stored threshold values for the patient un der test. The display can
be tilted to improve the viewing angle for an individual user and to allow easy access to the
rear jack panel.

Introduction

The GSI 61 Clinical Audiometer is a microprocessor controlled,
two channel audiometer for use in the clinical/diagnostic
environment. It has two separate sets of controls, one for eac h
of the channels. Each channel can be operat ed indepe ndentl y
by its tone bar, or the two channels can be activated
simultaneously through use of the interlock button.

The GSI 61 permits the output routing of the test signal through
earphones (matched TDH-50P), a bone vibrator (B71), optional
loudspeakers, optional paired I nsert Phones (EAR) or sing le
Insert Phone, and optional High Fre quency ( Sennheiser HDA

200) Earphones.

The diagnostic tests are easily selected through use of the
ergonomically designed front key panel. Flexible routing
selections permit the user to select that which is appropriate

The GSI 61 provides testing capabilities for a standard battery of diagnostic audiometric tests
including ABLB, SISI, Tone Decay, Stenger, Doerfler-Stewart, Lombard, and Staggered
Spondaic Word test (using a three head tape recorder). The High Frequency option extends
the frequency range (from 8 kHz to 20 kHz) for ototoxic dru g monitoring.

The GSI 61 has the optional capability of printing the stored audiogram data or of sending the
data to a remote computer through an RS 232 or USB interface. The RS 232 and USB interface
a re bidirect ional to allow the operator to transmit test results to a computer and to control the
audiometer from a remote computer system. The transmittable data record can be configured to
be either a single value (threshold and frequency) or battery transfer (all stored parameters for
a patient).

1761-0100 Rev. B

1-1

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Blank page.

1-2

1761-0100 Rev. B

k

t

t

n

Chapter 2

Installation

External Inspection

Although this GSI 61 Clinical Audiometer was carefully tested, inspected and packed
for shipping, it is good practice after receiving the instrument to immediately examine
the outside of the container for any signs of damage. Notify the carrier if any damage
is observed.

Unpacking

Carefully remove th e GSI 61 from its shipping container. If the instrument appears
to have suffered mechanical damage, notify the carrier immediately so that a proper
claim can be made. Be certain to save all packing material so that the claim adjuster
can inspect it as well. As soon as the carrier has completed the inspection, notify
a Grason-Stadler representative.

If the instrument must be returned to the factory, repack it carefully (in the original
container, if possible) and return it prepaid to the factory for the necessary adjustments.

Check that all accessories itemized below are received in good condition. If any
accessories are missing, a Grason-Stadler representative should be notified
immediately.

Installation

2

See the Specifications Section of this manual for the catalog numbers of accessories
and also for a listing of the optional accessories.

Accessories Supplied

Test Microphone /
Monitor Headset

Patient Talkbac
Microphone

Patien

Handswitch

Response

Test Headset
Assembly

Bone
Vibrator
Assembly

Not Shown: For Sound Booth use:

her

O

1761-0100 Rev. B

Handswitch Patch Cord (1)
Bone Vibrator Patch Cord (1)
Earphone Patch Cord (2)

:

Instruction Manual.....Power Cord and

GSI Suite CD

2-1

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Connectors, Controls and Indicators
Rear Panel

R1 - Monitor
Headset

R2 - Ext A and Ext
B

The connectors on the rear panel of the GSI 61 are shown in the following diagram.
The label and jacks are visible looking down onto the instrument, behind the LCD.

R9 R8 R7 R6 R5 R4 R3 R2 R1

(Modular Phone Jack)

Pin Function

1

Mic High and +6 VDC 0.2 to 6.0 mV RMS 1.8 K ohm (output)

2

Phone Low GND 0 ohm

3

Phone High 3.0 mV to 1.0 V 300 ohm

4

Mic Shi eld GND 0 ohm

(RCA plug)

Output Voltage

Impedance

R3 - Talkback
Microphone

R4 - Left and Right
Ear

Phone Outputs

R5 - Left and Right

Input jacks for optional stereo tape cassette or CD player.

Voltage range required: 0.2 to 1.0 V to obtain 0 VU
Input Impedance: 15 K ohm

(3.5 mm stereo jack)

Position Function

1 Tip Mic High 0.2 to 2.0 mV RMS and +6V AC 10 K ohm
2 Ring Mic Low - - - - - - - - - -
3 Shield Chassis Ground - - - - - - - - - -

(1/4 inch stereo jack)

Stereo phone jacks for left (blue) and right (red) earphones, patch cords, or High
Frequency earphone connector cords.

Voltage: 1µV to 7.0 V RMS (4.45 V RMS for High Fre qu en cy )
Output impedance: 5 ohms or less

(1/4 inch monaural jack)

Output Voltage

Impedance

2-2

1761-0100 Rev. B

Chapter 2 - Installation

Insert Phone Outputs Monaural phone jacks for left and right insert phones or patch cords.

Voltage: 1µV to 4.0 V
Output impedance: 5 ohms or less

Note: When the Single Insert Phone option is used, it must be plugged into the left

insert phone output.

R6 - Bone Vibrator (1/4 inch phone jack)

Jack for bone vibrator or gray patch cord.

Voltage: 200 µV to 5.00 V RMS
Output impedance: 5 ohms or less

R7 - Subject (1/4 inch phone jack)
Response
Handswitch Accepts plug from the cable attached to the patient’s response handswitch or

handswitch patch cord.

Pin Function Voltage Impedance

1 Shield GND 0 ohm
2 Digital GND GN D 0 ohm
3

Response input +5V/GND 1K ohm/0 ohm

R8 - CD Player Power (2 pin power jack)
Jack

Provides 5 V DC for CD Player.

R9 - Dip Switch/Cal An eighth position bank of switches accessible by an authorized service representative.
Switch

R10 – Speakers (5 pin Din connector) Located on rear of instrument.

Connects to left and right loudspeakers.

Pin Function Impedance

1

Left speaker (high) 1.0 ohm

2

Left GND 0 ohm

3

Right speaker (high) 1.0 ohm

4

Left speaker (low) 1.0 ohm

5

Right speaker (low) 1.0 ohm

SHLD Right GND 0 ohm

1761-0100 Rev. B

2-3

r

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Left Side
Panel

Right Side
Panel

Please Note:

The connectors on the left side panel are shown below.

The power entry module is composed of the power
switch, fuse drawer and voltage selection switch,
and power cord with hospital grade plug appropriate
for the country of destination.

When turned ON, the GSI 61 automatically initializes and displays a screen which
states the type of audiometer (IEC and ANSI specified for speech audiometry)
followed by a status screen. With the status display, the GSI 61 is brought to the
initialization state.

The frequency is set at 1000 Hz and:

Channel 1 Channel 2

Steady tone NB Noise
Phone-Right Phone-Left
0 dB HL -10 dB HL

Serial Port

This instrument has Remote and Printing capability, or t h e f o l l o wi n g connectors will be
visible on the right side panel of the GSI61:

Depending on the
date product
configuration
purchased, the GSI 61
is either equipped
with a Serial Port, a
USB Port, or no
Remote port at all.

RS 232 Remote Port

USB Remote Port
Printe

USB Printer Port
DIP Switches

2-4

Port

!

RS232

Printer Port

Dip Switches

Remote Port

Remote/Printer Option

A mini-DIN connector uses a standard Apple “Hayes Modem” cable (supplied) to
provide serial connection to th e equi pment.

A Standard A/B USB cable provides connection to a PC.

A 25-pin PC-Printer Interface Connector. Connects to t h e printer via a standard PC­parallel printer cable.

A Standard USB cable provides connection to a printer. See Chapter 6 for more
For more detail on these DIP switch settings, and attaching and using a printer , refer to

the Optional Accessories section beginn ing on page 2-18.

1761-0100 Rev. B

Front Panel Controls

p

The controls on the front panel of the GSI 61 are shown below.

Chapter 2 - Installation

Attenuators
(HL Controls)
Channel 1
and Channel 2

dB Ste

Size

The GSI 61 contains two independent HL rotary controls for test signal and masking
intensity l evel control with a ra nge of -10 dB HL to 120 dB HL (If the High Frequency
option using Sennheiser earphones is installed and active, the High Frequency intensity
level control ranges from -20 dB HL to 1 10 dB HL). Maximum dB HL values appl y
to the mid-frequencies with earphones only. Refer to the specific transducer for dB
HL limits in the Table on page 2-24.

These pushbuttons allow the operator to change the intensity step size to 1.0, 2.0 or

5.0 dB. When the GSI 61 is powered up, the dB step size is automatically set to the
.

default of 5 dB increments

These pushbuttons are also used to select the intensity

increase when testing in the SISI mode.

1761-0100 Rev. B

2-5

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Signal Format (Frequency Modulation or Warble Tone)
Selectors FM - This pushbutton enables pure tones to be warbled at a rate of 5 Hz with a ± 5%

allowable deviation around the selected center frequency. FM is available in all pure
tone test modes, including SISI, Pulsed, ALT and High Frequenc y (optional).

Pulsed - This pushbutton causes the tone to be pulsed at the rate of 200 msec ON,
200 msec OFF. Note that the Pulsed tone is not available in SISI or ALTernate test
conditions. When a speech test mode is activated, Pulsed is no longer activated.

Alternate - This pushbutton locks both channels together and alternates the tone
presentation between the two channels: 400 msec ON Channel 1, 400 msec OFF
Channel 1, 400 msec ON Channel 2, 400 msec OFF Channel 2. Both channels
receive TONE as the input stimulus. The frequency is automatically set to 1000 Hz
and the dB step size, HL settings and the routing reflect the conditions prior to the
selection of ALTernate test type. The tones can be manually presented by depressing
either PRESENT bar or automatically presented by pressing either INTERRUPT
button. The intensity of the tones can be adjusted independently by use of the Channel
1 and Channel 2 attenuators.

SISI - This pushbutton provides an intensity increment every 5 seconds to a steady
or FM tone in the selected channel for 200 milliseconds. The SISI test may be run at
step sizes of 1.0, 2.0 or 5.0 dB. When SISI is selected, the GSI 61 automatically
initializes Channel 1 to receive tone and Channel 2 to receive NB noise. The step
size is initialized to 5.0 dB but may be changed to either 1.0 or 2.0 dB at any time
during the test. Channel 1 and Channel 2 are set to 0 dB HL; the frequency is set to
1000 Hz. Output transducer and routing reflects the state of the GSI 61 prior to the
selection of SISI. Depress the Interrupt pushbutton to allow the SISI increments to
be presented every 5 seconds. Press the Interrupt button a second time to terminate
the SISI presentation. (Operating the Channel 2 tone bar with Interlock selected in
SISI also terminates the SISI increment presentation).

In order to deselect the preselected signal format, change to any non-compatible test
stimulus or push the same signal format again. The following table illustrates the
compatibilities of test stimulus and signal formats.

VALID SIGNAL FORMATS / STIMULUS COMBINATIONS

TONE

MIC

FM

PULSED

ALT

SISI

V

V

V

V

X

X

X

X

EXT A

X

X

X

X

EXT B

NBN

SPEECH

WHITE

X

X

X

X

X

V

V

X

X

X

X

X

X

V*

V*

X

V =Valid combination of signal format and stimulus.
X = Invalid combination of signal format and stimulus.
* = When White/White is selected stimulus, calibration for White noise will

be for speech.

2-6

1761-0100 Rev. B

Chapter 2 - Installation

Stimulus Channel 1 Tone — The Tone pushbutton allows the selection of a pure tone presentation for
and Channel 2 air/bone conduction testing with the choice of four transducer types; Phone (both the

standard TDH 50P and the optional High Frequency earphones), Bone, Speaker, or
Insert. When Tone is selected, Narrow Band Noise automatically routes to the
opposite channel if the stimulus type on the opposite channel is not compatible with
Tone. Note that the selection of Tone on one channel and Mic on the opposite
channel is a valid combination. This setting allows the operator to have contact with
the patient, especially a young child, without the need to select Talk Forward.

Mic — The Mic pushbutton provides input capability from the test microphone for
live-voice testing with the choice of four transducer types: Phone, Bone, Speaker, or
Insert. When Mic is selected, Speech Noise automatically routes to the opposite
channel if the stimulus type on the opposite channel is not compatible with MIC.
Note that the selection of Mic on one channel and Tone on the opposite channel is a
valid combination. This setting allows the operator to have contact with the patient,
especially a young child, without the need to select Talk Forward.

Ext A, Ext B — External A and External B accept recorded speech material from
an optional compact disc player, a two channel tape cassette or a reel-to-reel tape
recorder . When Ext A or Ext B is selected on one channel, Speech Noise automatically
routes to the opposite channel if the stimulus type on the opposite channel is not
compatible with Ext A or Ext B. Note that the selection of Ext A, or Ext B, on one
channel and Tone on the opposite channel is a valid combination.

Narrow Band Noise — The NB Noise pushbutton selects narrow band noise.
This is a noise centered at each test frequency and available for all frequencies with
a 3 dB down bandwidth of greater than octave but less than ½ octave. The maximum
dB HL is 15 dB below the maximum pure tone level and is calibrated in effective
masking.

Speech Noise — The Speech Noise pushbutton selects speech noise. This is a
white noise filtered to a low and middle frequency band, simulating the average

.

spectrum of conversational speech

Speech noise is calibrated in effective masking
level and consists of equal energy per frequency from 250 to 100 Hz with a 12 dB/
octave roll-off from 1000 to 6000 Hz. The maximum dB HL for speech noise is
equal to the maximum HL for the speech type signals in each transducer.

White Noise — This pushbutton selects White Noise. White noise is a broad band
signal containing acoustic energy at all frequencies between 125 Hz and 12000 Hz.
White noise is calibrated for pure tone effective masking if a tone type signal is
selected on the opposite channel, and for speech effective masking if a speech type
signal is selected on the opposite channel. The maximum HL for white noise selected
with a tone signal is 35 dB below the maximum pure tone level. The maximum HL
for white noise selected with a speech signal is equal to the maximum HL for the
speech signal.

Refer to the following table for the stimuli compatibilities listing.

1761-0100 Rev. B

2-7

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Valid Stimuli Combinations

Channel 1 Stimulus

Mic

Ext A

Tone

Ext B NBNoise S Noise White Noise*

* If White Noise is selected
on both channels, then
calibration is made to speech.
If White Noise is selected on
one channel only, calibration
will be made to the stimulus
type on the opposite channel.

Transducer Output
Selector

Channel 2

Stimulus

Tone

Mic

Ext A

Ext B

NBNoise

S Noise

W Noise*

Valid

Valid

Valid

Valid

Valid

Invalid

Valid

Valid

Valid

Valid

Valid

Invalid

Valid

Valid

Valid

Valid

Valid

Invalid

Valid

Valid

Valid

Invalid

Valid

Valid

Valid

Valid

Invalid

Valid

Valid

Valid

Valid

Invalid

Valid

Valid

Invalid

Invalid

Valid

Invalid

Invalid

Valid

Valid

Invalid

Valid

Invalid

Valid

Valid

Invalid

Invalid

Valid*

These pushbuttons allow the easy selection of the transducer for each stimulus
available for Channel 1 and Channel 2. A transducer selection may be changed at
any time.

Valid Transducer Combin ation s

Channel 1

Bone

Speaker Insert

Valid

Valid

Valid

Valid

Valid

Valid

Channel 2

Phone

Bone

Speaker

Phone

Valid

Valid

Valid

Valid

Valid

Valid

Routing Output
Selector

Tone Bar / Interrupt

Insert

Valid

Valid

Valid

Valid

These pushbuttons allow the easy selection of the routing from the stimulus to the
output transducer available for Channel 1 and Channel 2. When first powered on,
the routing for Channel 1 will be right and the routing for Channel 2 is left. Left/
Right mixes the stimuli from both channels to each transducer and drives both the
left and right transducers with the combined signal. Both the Channel 1 and Channel
2 maximum dB HL limits in mixing are appropriately decreased from the non-mixed
maximum dB HL limits. Left/Right -Left/Right routing is restricted to Phone/Phone,
Speaker/Speaker and Insert/Insert (paired insert option). Left/Right routing is invalid
for bone and the single insert phone.

Each tone bar operates independently to present the selected stimulus for as long as the
bar is depressed. The channel turns off immediately when the bar is released. When
ALTernate is selected and the tone bar is released, the complete presentation of
both channel signals is completed. These pushbuttons determine the status of the
respective tone bars and operate independently of each other. When the Interrupt
is in the off position, the corresponding channel is activated by depressing the Tone bar
bar and deactivated by releasing the Tone bar. To turn on the Interrupt, press the
pushbutton. When Interrupt is in the on position, the corresponding channel is deactivated
by pressing the Tone bar and activated by releasing the bar. When Interrupt active,
an icon is displayed on the LCD. Note that in the ALTernate test mode, the Interrupt
pushbuttons do not operate independently of each other.

2-8

1761-0100 Rev. B

Chapter 2 - Installation

Interlock This pushbutton locks both tone bars together so that operating one channel will also

operate the other, according to the status of the Interrupt buttons. To unlock the
Tone bars, press the Interlock button again. When the Interlock is active, a message
is displayed on the LCD.

Save This pushbutton, when pressed, saves the current dB HL level representing the

threshold level, and effective masking level if selected, transducers and routing. In
the Display Audiogram format, the appropriate symbol appears for each Save press.

Tracking

This pushbutton allows the Channel 2 hearing level to track the Channel 1 hearing

level by a selected dB difference. When in Tracking, any dB change to the Channel
1 HL causes the Channel 2 HL to change by the same amount, until the limit of the
Channel 1 transducer is reached. If the dB HL limit is reached in Channel 2 before
Channel 1, the Channel 2 dB HL display will temporarily flash and remain at this
level. Tracking remains on. When the Channel 1 dB returns to a level at which the
selected difference between the two channels can resume, Channel 2 again tracks
Channel 1. Tracking is in the off state upon initialization of any test type. When
tracking is selected, it is possible to manually change the intensity of Channel 2 to
alter the dB difference between the two channels without deselecting Tracking. To
exit T racking, press the button again. When T racking is active, a message is displayed
on the LCD.

Frequency Up/Down These pushbuttons allow the choice of twelve standard audiometric frequencies: 125

Hz, 250 Hz, 500 Hz, 750 Hz, 1000 Hz, 1500 Hz, 2000 Hz, 3000 Hz, 4000 Hz, 6000
Hz, 8000 Hz and 12000 Hz. If the high frequency option is activated, these pushbuttons
allow a choice of nine high frequencies: 8 kHz, 9 kHz, 10 kHz, 1 1.2 kHz, 12.5 kHz,
14 kHz, 16 kHz, 18 kHz, and 20 kHz. Each press of the right (R) pushbutton selects
the next higher frequency. Each press of the left (L) pushbutton selects the next
lower frequency. The new frequency is selected when the pushbutton is released.
When at the lower limit of the frequency selection, pressing the (L)pushbutton will
cause the display to roll over to the highest frequency limit, and vice versa. If a
transducer with a narrower range is selected, only valid frequencies for that transducer
are available.

See the Table entitled “dB HL Limits per Frequency and T ransducer” in the Hearing
Limits and Frequency Levels Section (pages 2-24 and 2-25) for the allowable
frequency ranges of the specific transducers.

Talk Forward Pressing this pushbutton allows the operator to speak directly to the patient through

the microphone at the level set by the Talk Forward control by interrupting the stimulus
presentation. Talk Forward can be used with any available transducer , including the
optional High Frequency earphones. While Talk Forward is on, the only control
which can be activated is the Print, if available. The GSI 61 resumes the test status
held prior to pressing the Talk Forward pushbutton when the pushbutton is released.

1761-0100 Rev. B

2-9

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Scorer/Timer The Correct, Clear and Incorrect pushbuttons are used for scoring results in Speech,

ALTernate or SISI tests. The scorer is displayed in the test status area of the Status
screen. When Speech, SISI or ALT is selected, the scorer initializes to 0/0 = 0%.
The operator presses the Correct or Incorrect pushbutton after each presentation,
depending on the response. The display indicates the number of correct responses
and the total number of presentations along with the percentage of those correctly
identified. The display clears with the pressing of the Clear pushbutton.

During tone tests (excluding ALTernate and SISI), the Scorer/Timer pushbuttons
may be used to start, clear and stop the timer. The timer is displayed in the test
status area of the Status screen. When the timer is first selected, it initializes to 0:00
(0 minutes: 00 seconds). The timer starts when the Start pushbutton is pressed.
Times up to 199 minutes and 59 seconds may be displayed before the timer resets to
0:00. The timer may be halted at any point by pressing the Stop pushbutton. The
stopped time is displayed.

Upon pressing the Start pushbutton after the Stop

pushbutton, timing is resumed from the currently displayed value. Pressing Clear
while the timer is running is invalid. Pressing Clear after Stop resets the timer to
0:00.

Displays These pushbuttons are used to select the format for the screen display format on the

LCD.

Display Status — When the Display Status pushbutton is pressed, the display is
formatted as shown in the following Figure: Front Panel Display - Status. This
display indicates the current instrument state and VU meters.

Display Status

Display Audiogram — When the Display Audiogram pushbutton is pressed, the
display is formatted as shown in the following Figure: Front Panel Display -Audiogram.
Two audiograms with the standard range of frequencies (125 Hz to 12,000 Hz), or
the High Frequency ranges (8 kHz to 20 kHz), and the instrument status are displayed.
Hold the Display Status key for 2.5 seconds to view the left audiogram on the left
side, and right on the right side. Hold the Display Status key again to reverse back
to the original setting..

2-10

1761-0100 Rev. B

Chapter 2 - Installation

Display Audiogram

High Frequency — When the High Frequency pushbutton is pressed with the High
Frequency option installed, the system allows tone testing in the extended range
from 8 kHz to 20 kHz. The display remains in the Display Status or Display Audiogram
format as previously selected. If the High Frequency option has not been installed
and the pushbutton is pressed, the error message “Not Available” appears in the
error message area of the display.

1761-0100 Rev. B

Display High Frequency

2-11

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Print Audiogram If the printer option is available and the Print Audiogram pushbutton is pressed, the

current saved test information in audiogram format is sent to the printer. If there is
no data stored in the GSI 61 memory and the Print Audiogram pushbutton is pressed,
the message “No Test Data Stored” appears in the error message area. If the
printer option is not active and the pushbutton is pressed, the message “Not Available”
appears.

Remote

When the Remote (RS232 or USB) option is installed, pressing the Remote pushbutton
allows the GSI 61, when connected to an external computer, to transmit and receive
data from this device. If the option is not installed and the pushbutton is pressed,
the message “Not Available” appears.

Data Transfer

When Remote is enabled and the Data Transfer button is pressed, a data record
containing the stored test data in a previously selected format is transmitted to a
remote device. Data may be transferred point-by-point or as a complete battery of
all saved test results. The data transfer format is set by an authorized GSI Service
Engineer. If the pushbutton is pressed when the Remote option is not active, the
message “Not Available” is displayed.

Data Erase When the Data Erase pushbutton is pressed for at least 0.5 second, all of the stored

test data in the GSI 61 is erased and the message “Erasing Data” is displayed on the
LCD. If no data is stored in the GSI 61 memory, the message “No Test Data
Stored” is displayed.

Contrast

This rotary control is used to set the brightness of the LCD.

Mic, Ext A and Ext B Level Controls

These rotary controls are used to adjust the signal intensity from the test microphone
or the external devices, so that the level reflects accurately on the VU meters on the
Status display. These inputs are adjusted by turning the appropriate control until an
indication of 0 dB on the average is obtained on the selected channel VU meter.

Note: it has been suggested that for live voice speech testing, the operator should
calibrate the GSI 61 to a 1000 Hz pure tone introduced into the microphone. When
using an external source, calibrate to the 1000 Hz pretest tone.

Talk Forward Level Control

This rotary control allows the operator to adjust the intensity in a continuous range of
45 to 90 dB HL when givin g the subject instructions through use of the Talk Forward
function. The level select ed by this control is calibrated to the transducer currently
being used with the subject.

2-12

1761-0100 Rev. B

Chapter 2 - Installation

Monitor Controls The Monitor Headphone or Speaker allows the operator to listen to the stimuli as

they are presented or to listen to the patient’s comments through the talk-back system.
The Channel 1 and Channel 2 rotary controls adjust the intensity of the sound
presented through the monitor headphone or speaker. The Talkback rotary control
adjusts the intensity of the patient’s voice. The Monitor Spkr pushbutton is used to
turn on the Monitor Speaker. When Mic is selected, or when the Talk Forward is
operated, that channel’s input to the monitor speaker is disabled to reduce acoustic
feedback.

Power This Power Monitor green light emitting diode (LED), located in the upper left portion

of the keypanel, is illuminated when power is supplied to the GSI 61.

1761-0100 Rev. B

2-13

Grason-Stadler GSI® 61 CLINICAL AUDIOMETER

Displays

A Liquid Crystal Display (LCD) is hinged to the GSI 61 and is used to display all of
the testing information from the instrument. When the LCD is in the lowered position,
easy access to the rear connector panel is provided.

The data from the GSI 61 is provided in two formats, Instrument Status and Audiogram.
The following figure shows the Instrument Status screen.

e

f

a

{

d

{

h

a.

b.
c.

d.
e.

f.
g.

h.

c

b

{

g

}

h

The output, in dB HL, for Channel 1 and Channel 2.
A graphical representation of the VU meters for each channel.
The tone ON icon which is displayed when the presentation is made.
The stimulus, transducer and routing currently selected for each channel.
If the Interrupt is on, this is also displayed in this area.
Frequency, in Hz, selected for Channel 1 or Channel 2.
The indicator bar for the subject response displays when the handswitch is depressed.
When a speech type condition is selected, this area is blank.
Timer/Scorer.
General system state, including tone presentation format, dB step size, special tests, monitor
speaker, High Frequency (optional), Remote (optional) with data transfer, and print
(optional).
Error messages/status messages. Refer to Chapter 7 for a description of the error and status

}

a

h

2-14

1761-0100 Rev. B