Welch Allyn GSI 17 User manual

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Covers Welch Allyn AM232 Manual Audiometer

Operation Manual

Warranty

We, Grason-Stadler, Inc. 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.

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 service 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.

If within one year after original shipment it is found not to

NOTE

Changes in the product not approved in writing

Grason-Stadler shall void this warranty. Grason-Stadler shall not be liable 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, EXPRESS OR IMPLIED, INCLUDING BUT

NOT LIMITED TO, ANY IMPLIED WARRANTY OF

MERCHANTABILITY OF FITNESS FOR A PARTICULAR

PURPOSE.

GSI

Grason-Stadler

A Welch Allyn Company

Grason-Stadler, Inc.

1 Westchester Drive

Milford, NH 03055-3056

Telephone: 603-672-0470

Fax: 603-672-0487

Service

Manual 1717-0110,,

Printed January, 1991

Printed April, 1991 Printed January, 1992 Printed January, 1994

(#1)

(#2)

(#3) (#4)

Rev.

Warranty

Table of

Warning

...........................

.L.

..............................

Key to Symbols Used on Schematics Foreword

...........................

SECTION 1- PRODUCT SPECIFICATIONS

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

1.10

1.11

1.12

1.13

1.14

1.15

1.16

1.17

1.18

Catalog Listings Standards

.....................

Test Stimulus

..................

Output Hearing Level Controi Signal to Noise Ratio Tone Switch Stimulus Transducers Front Panel

....................

......................

................

Controls/Rear Power and Power Line Battery Pack Voltage

...............

................

Environmental Conditions Mechanical Dimensions Material Used in Leakage Test

Manufacture

....................

Headband Static Force

..............

...............

Earphone Cushion Attenuation

Accessories

....................

..............

............

Panel Connectors

..............

............

.....

: : 1

iii

vii

viii

1 1 1 2 2

3 3 5 5 5

6 6 6 6 6 7

SECTION 2

FUNCTIONAL DESCRIPTION

Figure 2-l:

2.1

2.2

2.3

2.4

2.5 SECTION 3

3.1

3.2

3.3

3.4

Front Panel Controls and Indicators Rear Panel Connectors and Controls General Operation of Controls

Power Up Initialization

Sleep Mode

ROUTINE MAINTENANCE

Earphone Cords

Hum and Random Distortion and Special Messages

3.4.1 CAL

3.4.2

Exx

Connectors, Controls, Indicators

........

.........

...........

..............

.....................

..................

Noise

Frequency Shift

..........

.......

..................

...

: :

........................

. . .

iii

9 10 10 10 11

13 13

13 14 14 14

SECTION

4- CALIBRATION

4.1

4.2

4.2.1

4.2.2

4.3

4.4

4.5

4.5.1

4.5.2

4.5.3

4.5.4

4.5.5

4.5.6

4.5.7

4.5.8

4.5.9

4.5.10

4.5.11

4.5.12

4.6

4.7

4.8

4.8.1

4.8.2

4.8.3

4.8.4

4.9

4.9.1

4.9.2

4.9.3

4.9.4

4.9.5

Quick Reference Calibration Figure 4-l: Figure 4-2: Table 4-l: Calibration Mode Operation

Quick Reference Calibration Control; Access to Calibration Controls Calibration Reference Threshold;

...........................

..........

....

Cal/Normal Switch Calibration Mode Dip Switches Calibration Mode Entry Mode Initialization Earphone SPL Tone Type Switch

Calibration Mode

..................

...............

............................

............

Routing Switch Frequency Selector' Present Bar

HLl

Extended Range

.....................

...

Pushbution

Response Switch

HLDisplay

Response LED

Stimulus ON

.....................

....................

.....................

Low Battery Segment

"+"

LCD Segment Calibration Mode Exit Calibration Data Storage and Validation

Calibration Mode Dip Switch Dip Switch S4 Dip Switch S3 Dip Switch S2 Dip Switch

....................

Selection of the Diagnostic Mode Hardware Diagnostic Test (DO) Pushbutton Diagnostic Test

..................................

................................

...................

.................

...................

................

.............

............

(D1)

.......

..........

...........

Display Diagnostic Test (D2) A/D Converter Diagnostic Test Attenuator Maximum Output Level Calibration

(D3) 1

(D4) .

: : 1 : 1 1 : :

: :

17 18 19

19 19 20 21 21

2";

22 22 22

23 23

23 24 24 25 25 25 27 27

29 31 33

SECTION

Figure 5-l:

5.1

Disassembly Instructions

5.2

5.3 SECTION

Accessories and Replacement Parts

6.1 Diagnostic Mode (DO)

6.2

6.3

DISASSEMBLY

Disassembly

Parts Numbers

TROUBLESHOOTING

....................

..............

..........

Troubleshooting Using the Hardware

............

Figure 6-l:

Diagnostic

Functions Output Related Figure 6-2:

Troubleshooting Block Diagram of Amplifier Signal Flow

Left or Right Amplifier Troubleshooting Symptoms'

Mode

Controls and

..................

Symptoms

...

.......

45 46

48 48

FOREWORD

GENERAL SERVICE INFORMATION Operating,

can be found in the Instruction Manual (1717-0100). and/or bench testing of GSI 17 Audiometers should only be performed by trained personnel. The following instructions are provided primarily for use by persons who are skilled in the

repair of electronic equipment. CMOS HANDLING PRECAUTIONS Many of the integrated circuits on the P.C. boards are CMOS and

NMOS type.

Failure to observe the following precautions whenever a circuit board or an integrated-circuit package is handled can result in damage to the GSI 17.

Place instrument and parts on a grounded, conductive work surface.

Ground yourself (with a strap having about 1 M ohm resistance).

Ground the frame of any test instrument or soldering iron to

be used.

check-out procedures,

CAUTION

trouble-shooting hints, etc.,

Repair

If any circuit boards are

enclose them in conductive (anti-static) envelopes.

to be stored or transported,

SECTION 1

._-

Product Specifications

1.1 CATALOG LISTINGS

1717-9700

1717-9710 GSI 17 Audiometer, 1717-9705 GSI 17 Audiometer, AC Power (Export) 1717-9715 GSI 17 Audiometer,

1.2 STANDARDS

This unit is a single channel,

is equipped with pure

conduction transducers (TDH39 Earphones). ANSI S3.6 and IEC 645 Type 4 Audiometer Standards.

The GSI 17 is designed to meet current revisions of the following

standards and specifications for audiometers:

GSI 17 Audiometer, AC Power (USA)

AC Power and Battery (USA) AC Power and Battery (Export)

pure tone screening audiometer.

tone stimulus signals, and air

This instrument meets

ANSI S3.6

IEC 645 IS0 389 IEC 601

1.3 TEST STIMULUS

PURE TONE SPECIFICATIONS A pure tone is the only stimulus source for this audiometer.

DISCRETE FREQUENCIES 125, 250,

FREQUENCY ACCURACY

< +3%

TOTAL HARMONIC DISTORTION (FROM 125 ACOUSTICALLY)

500, 750, 1000, 1500, 2000, 3000, 4000, 6000, 8000 Hz

Frequency

125Hz 1000 3000

Hz Hz

Test

100

Hz TO

4000 Hz, MEASURED

<2%

1.4 OUTPUT HEARING LEVEL CONTROL

CALIBRATED IN dB MEASURED IN INCREMENTS OF 5

RANGES

-10

125

Hz 500to 250

6000

and

Additionally A

Hz -10

8000

"+10 dB""

-10

Extended Range

maximum HL at all frequencies by 10 ACCURACY OF ALL SETTINGS

125 to 4000 Hz

6000 to 8000 Hz

1.5 SIGNAL TO NOISE RATIO (IN

>70

dB measured acoustically in dB HL

1.6 TONE SWITCH

This

electronic

switch turns the stimulus

HEARING LEVEL CONTROL:

+5 dB

1/3

dB.

OCTAVE)

minimal audible distortion.

dBB

HL Switch,

which

signal

extends

ON/OFF with

MODES

Normal State: Activated State:

Stimulus OFF Stimulus ON

RISE/FALL TIME

20-50

Measured at the -1 dB and

-20

points on the signal envelope.

ON/OFF RAT IO

With

the

Tone Switch OFF,

below standard reference equivalent threshold for any

the output will be at

least

1/3

-10 octave

dB band with HL setting of 60 dB or below. ABOVE 60 dB HL SETTING

>70

dB CROSS CHANNEL LEAKAGE At HL settings of 70 dB or greater,unwanted signals in the

non-

test earphone shall be at least 70 dB below the tone in the test

earphone.

dB2

1.7 STIMULUS TYPES

Continuous Tone Continuous FM Tone Pulsed Tone

SIGNAL FORMAT Continuous Pulsed

Pulsed Rate:

Signal steady as long as Present Bar is depressed.

2.5

Pulses/sec Pulse rate is synchronized to the "Present first and last pulse will have 200 ms on time.

DUTY CYCLE

50%

RISE/FALLTIME

20-50 ms

ON/OFF RATIO (BETWEEN PULSES)

>20

FREQUENCY MODULATION

FM Rate: FM Deviation:

5 Hz

25%

Bar"

so that

the

1.8 TRANSDUCERS HEADSET TDH39 Earphones with 60 ohm impedance

1.9 FRONT PANEL CONTROLS AND REAR PANEL CONNECTORS

FRONT PANEL

CONTROLS

Frequency Selection HL Select Mode Selector (Pulsed/Steady/FM) Routing (Left/Right) Present Bar Power Switch

"+10 dB"

Push-Button

INDICATORS:

Power ON/OFF Frequency Selector dB

HL - LCD Left/Right Earphone Pulsed/Steady/FM

Subject

"Battery

Response - LED

Low"

(when applicable, i.e. Battery Option

purchased) - LCD Tone ON - LED Extended Range - LCD

REAR PANEL CONNECTORS

Left and Right Earphone -

Subject Response Switch

- 1/4"

Power Cord- 5 Pin DIN

LEFT AND RIGHT EARPHONE JACKS Pin#

Tip Sleeve

SUBJECT SWITCH

--Pin&

Tip Sleeve

POWER INPUT

Function

Phone High

25 u VRMS to 2.5 VRMS

Phone Low

(J7)

Function

Switch High Switch Low

(J1)

Battery Power No Power Module

Pin #

Name

Attached

1/4"

Phone Jack Phone Jack

(J4 & J5)

Output Voltaqe

0 Volts

Output Voltaqe

Vdc

0 Volts

Power Module Connected w/NiCad Battery

Installed

Impedance

(max)

130 ohms

0 ohms

Impedance

47 K ohms

Power Module Connected w/Alkaline Battery Installed

ohms

Power Module Only

Battery

J1-1 J1-2

Jl-3 Jl-4 J1-5

VSUP

CHASGND PROTECTIVE

GND

CGND

0 (REF) BAT/LINE 2.6 to 3.0 VBAT

+7.3

to 9.0

PROTECTIVE

GND

0 (REF)

3.7 to 4.3 +7.0

All values listed are in Volts DC

to 9.0

NC PROTECTIVE GND

0 (REF)

3.7 to 4.3

7.0 to 13.5

t9.0 to 16.0 PROTECTIVE

GND

0 (REF)

4.3 to 5.1

+7.5

to 13.5

1.10

POWER AND POWER LINE

POWER RATING

9 Watts power module operated while simultaneously charging battery.

0.6 Watts battery power

OPERATING MODES

Power Line (Mains) Battery- Rechargeable

(NiCad)

or Non-Rechargeable (Alkaline)

LINE (MAINS) VOLTAGE

115 V or 220 V

LINE (MAINS) VOLTAGE VARIATION

+lo%

LINE (MAINS) FREQUENCY RANGE

50-60 Hz

LINE (MAINS) FREQUENCY VARIATION

+5%

1.11

BATTERY PACK VOLTAGE

BATTERY VOLTAGE OPERATING RANGE

7.0 v to 9.0 v

BATTERY PACK TYPICAL OPERATING LIFE

NiCad: Alkaline:

22 Hours 45 Hours

1.12 ENVIRONMENTAL CONDITIONS

OPERATING TEMPERATURE RANGE

15 to 40 Degrees Celsius

SHELF TEMPERATURE RANGE

Power Module Operated:

-40 to 60 Degrees Celsius

Battery Operated: -40 to 40 Degrees Celsius

RELATIVE HUMIDITY RANGE

5% to 90%

1.13

MECHANICAL DIMENSIONS

Weight:

5.6 lbs (2.53 Kg) Weight of Battery Pack: Size:

13.25"W

14"D

1.5 lbs (0.68 Kg)

3.75"H

(33.66 cm x 35.56 cm x 9.53 cm)

1.14 MATERIALS USED IN MANUFACTURE

GSI 17 Case Assembly

GE Cycolac T Battery Option Case Assembly - GE Cycolac T Power Module Case Assembly - Noryl SE -

100J

(Flame Retardant)

1.15 LEAKAGE TEST (AC) CONNECTED/SAFETY TEST

Leakage Current High Voltage Breakdown

<25 uamps

115 V operation 220 V operation

>3000

>4000

v v

1.16 HEADBAND STATIC FORCE

1.6 to 2.0 pounds when

earcups

are 5.7 inches

apart.

Measured

with distance center of headband to center of earphones equal to

5 inches.

1.17 EARPHONE CUSHION ATTENUATION

Frequency (Hz)

125 250 500 750

1000 1500

Attenuation

6.5

4.5

7.0

10.0

15.5

18.5 2000 26.0 3000 4000 6000 8000

30.5

33.0

27.0

24.5

1.18 ACCESSORIES

Supplied Cataloq Numbers

Test Headset (TDH39) Audiogram Forms (1 pad of 50)

Instruction Manual

Battery Pack Assembly

(used with 1717-9710,

1717-9715 models only)

8000-0175 1717-9600 1717-0100 1717-2010

AC Power Cord,one of the following:

120 v (US) 220 V (Euro plug) 240 V (UK) 220 V (Generic)

8000-0240 8000-0241 8000-0242 8000-0250

GSI 17's with serial numbers below # 0856 require a different power module.

See Section 9, Power Module,

for details. Optional Catalog Numbers Response Handswitch

Patch Cord, 2 Conductor Audiocups Battery Pack Assembly

7874-0156 4202-0505 8000-0155

1717-2010 Battery Pack includes GSI supplied NiCad Battery. May also be used with six

(6),

Size C, Alkaline

Batteries (not included)

Replacement NiCad Battery

8410-0060

Figure 2-1:

CONNECTORS, CONTROLS, INDICATORS

SECTION

This

Connectors,

Figure

Controls,and Indicators.

2.1 THE FRONT PANEL CONTROLS AND INDICATORS (FIGURE 2-1)

section of

2-l for the layout and positioning of

F2 - Range

Present Bar for stimulus presentation.

Functional Description

the Service Manual is

Controls,

Power switch and indicators for ON

increase standard operation is indicated by the LCD.

HL control for setting stimulus Level indicated on LCD.

and Indicators of the GSI 17.

extension pushbutton allows

the

stimulus intensity 10

maximum

HL at

used to

any

frequency

"+"

being lit on

intensity

describe

Refer to

all

(1)

Connectors,

and OFF (0).

operator to

above

level.

the

its

the

F6 - Subject response

F7 - Frequency

F8 - Routing

F9 -

F10 -

Loudspeaker

presentation indicated by illuminated LED.

that the test button.

control for setting stimulus

Frequency indicated in window adjacent to control.

switch for routing the stimulus signal to

the

indicated by illustration of

Tone

type.

---

Low battery indicator to alert the

the available depending

are used).

left or

type

= warble tone = steady tone = pulsed tone

batteries

switch for setting

(recharge or

on whether

in operation as such.

indicator LED shows the operator

subject

right

have a

has pressed the handswitch

earphone.

limited replace

NiCad

Left or

subject.

the

alkaline

stimulus

operator

operating

batteries

Actual

frequency.

right

soon,

batteries

tone

when time

2.2 REAR PANEL CONNECTORS AND INDICATORS

R1 -

Power input position

and rear panel indication of input

jack with front panel

indication of

power

specifications.

Attention,consult accompanying documents.

Earphone output jacks with front panel

indication of left and right phone provided by illustration of subject.

Subject response switch input jack with front panel

indication of position.

Calibration switch indication.

2.3 GENERAL OPERATION OF CONTROLS

All

initialization is complete, in

depends on the HL selection. When the Extended Range is

controls

this

document and for the Extended

are

valid at

except for special cases as indicated

all

times

Range

once

the

Pushbutton

power up

which

invalid there will be no indication given to the operator other than absence of the

"+"

LCD segment.

the

All polled

state.

All operations of all controls are

controls are checked every 12

msec

for a

debounced

change in

for 12

msec

before processing. The

Extended

manner.

and

hold manner (except in the Calibration and Diagnostic modes

The Present Bar and Response Switch operate

Range pushbutton operates by a push ON,

by a

push OFF

press where the Present Bar is push ON, push OFF). When a press and hold type control is operated all other controls

are still active.

When the operation of a control is being processed the processing

all

other controls is delayed until the first

operation is

completed.

2.4 POWER UP INITIALIZATION

When

the power switch is set to the ON position

the

instrument

will go through the following initialization process:

All microprocessor

internal

and

external

hardware

components of

system will be initialized for the

the

required

type of operation.

All

LEDs

and LCD segments will be turned on to indicate that

the power up initialization is in progress.

The RAM will be tested using a read after write verification process.

initialized will be displayed on the HL display and the instrument halt.

After each location is tested its value

to 0.

If an error is detected, an

will be

error

code will

The generate a stored in the EPROM. using any of the RAM. will be displayed on the HL display and the instrument halt.

The operating mode of the instrument will be determined by

the position of the Cal/Normal Switch and the four Cal Option Dip Switches. Refer to Sections 3 for the Calibration and Diagnostic Mode initialization. remaining initialization process will be performed for the Normal Mode.

The

initialized to 0 HL.

analog hardware

selections. After

all controls active.

2.5 SLEEP MODE

EPROM will be tested by reading the complete

current

initialized to their currently selected positions.

initialization,

EPROM to

checksum which will be compared to a

This test will be performed without If an error is detected an error code

HL selection

All other controls and displays

will

be initialized

the instrument will remain idle

and

the

HL display

according to

checksum

will be

will

The

will

All

these

with

The GSI 17 has a mode which is designed to lengthen battery life. When operation Sleep only when the unit available when connected to mains (ac) power.

If a period

operated (front panel, internal,

"sleep",

Prior to entering the Sleep Mode,

indicate 3 dashes ' - - -

mode status.

7 Volt) which will disable much of the analog circuitry.

the disconnected, a STOP state which will halt its operation.

The either the Present Bar or power switch are toggled.

the

unit

Sleep

unit has been left on, under for

Mode.

thus drawing minirnal current.

enters

more than 5 minutes, the GSI 17 will

It is important to emphasize that this mode

is operating with batteries, and is not

of 5 minutes has elapsed

external) the unit will go to

the display will be updated to

to advise the operator of its

It will also disable the voltage converter

the

the channel will turn OFF and the CPU

Mode is exited, and normal

sleep

mode,

battery power,

since

all

transducers

operation

any control was

resumed,

without

enter the

exists

sleep

(+7

When

will be

will

enter

when

SECTION 3

3.1 EARPHONE CORDS

With extended use,earphone cords tend to fray internally at

junctions with

fraying associated cord is flexed.

check control (F7) to 1000 or 2000 Hz, set HL control (F3) at a comfortable audible level,

earphone cord intermittent

scratchy the conditions signifies that the cord should be replaced.

Repeat the test for the other earphone.

3.2 HUM AND RANDOM NOISE

will ultimately either decrease the signal level in

earphone or cause signals to be intermittent as

for

signal,

sound superimposed over the signal that coincides

flexing of the cord.

Routine Maintenance

both earphone and audiometer

either condition, set

press the Present Bar (F4)

next to plug at

abrupt

changes in

The presence of any of

the

both ends,

audiometer

signal

the

connectors. This

the the

frequency

and

listening

level, or a

these

flex

for

with

three

This test can be made during the check for attenuator noise. With the instrument set on 1000 Hz,

0 to 60 dB and listen for low-frequency hum (60 to 120 Hz) and

random noise (hiss or low rushing

levels. permissible.

audible.

naive subjects and affect the accuracy of the audiogram.

Schedule the audiometer for immediate service if any of these

symptoms are detected.

3.3

DISTORTION AND FREQUENCY SHIFT

This check is most easily performed by listening to the output of

the

frequencies at

dBHL for normal ears). Listen for rattling, rasping or distortion in the tones

presented. change when the Frequency Selector (F5) is moved to a new position. other,

should be replaced. In any case,the audiometer should be

immediately scheduled for maintenance.

GSI 17

Some audible random noise at levels above 60 dB is

Below 60

Any of these noises can be confused with the signal by

through

a loud,

Listen also to ascertain that signal frequencies

If distortion is heard in one earphone but not in the

the chances are high that the earphone is at fault and

however, only the signal should be

the

earphones

but not uncomfortable, level (70 to 80

move the HL control (F2) from

sound) at all attenuator

while

presenting

all 11

3.4 SPECIAL MESSAGES

The

GSI 17 is a

microprocessor-controlled performs a self check each time the instrument is turned on self check does not occur when the instrument is "awakened" sleep mode).

the front panel LCD if any error in the instrument

is detected.

Certain messages will be displayed to the

These messages are described below.

instrument

operator

operation

which

(the

from

3.4.1 CAL

When a

calibration

"CAL" will be displayed to the operator.

function at

invalid results displayed as long as the "problem" transducer and frequency selected. changing either

transducer or frequency is

error

this

can be

(i.e.

frequency with this transducer, so

right earphone at 2000

recorded.

The word

If the calibration error is an

the

frequency or

the

selected

which

Hz),

has a

the

word

The audiometer will not

that no

"CAL"

will be

are

isolated

transducer

situation,

(i.e. left

earphone or 3000 Hz) will restore normal instrument function.

As is

service technician should be contacted immediately.

make

the

case with any instrument

malfunction, a

note of the combination of transducer and

certified

Remember to

frequency which

resulted in the "CAL" message.

3.4.2 Exx

When an error code consisting of an

"E"

and a 2-digit number (xx,

= number) appears on the audiometer's display, a system error has

been detected. not will

permit the instrument to operate.

remain on

instrument will

The GSI 17 will enter a "lockout" mode which will

the

display

shut

The specific

for

several

seconds,

itself down completely.

error

then

Should an

code

the Exx

appear on the LCD,take the following steps:

Power down,

then power up again.

This error could be only a temporary failure and may never appear again. However,

should the Exx message

reappear,

proceed to

steps b. and c.

Record the numbers that appear on the display. Contact your certified service representative and give

them the specific numbers you have recorded.

4.1 QUICK

REFERENCE

CALIBRATION

--X

a. b.

Select Calibration Mode using Cal/Norm Switch. Select Frequency and Reference HL for calibration. Select Earphone Routing (L or R). Turn Tone ON using Present Bar.

NOTE:

Display will update to the ANSI proper calibration as necessary.

e. f.

Adjust Output Level to the required SPL using the HL Dial. Store data using the

LCD Segment will illuminate to indicate storage of data.

g. h

NOTE:

REPLACED,

Repeat for all frequencies. Repeat for opposite earphone.

. .

Return Cal Switch to NORM position.

If A CAL ERROR occurs or the MICROPROCESSOR HAS BEEN

the following steps should be performed:

Short

JP1

pins 1 and 2 then power-up for 2-3 seconds.

Power-down and remove jumper.

6.6).

SPL required for

subtract or add microphone

+10 dB

Range Extender Pushbutton

(See Troubleshooting, Section

corrections

(+)

Load Default Data. (See Dip Switch 4, this section). Battery low/shut down calibration.

(See Diagnostic Mode

(D3), this section).

Attenuator maximum output level calibration. Diagnostic Mode

(D4),

this section).

Proceed with Transducer Calibration.

(See

NORMAL/CAL MODE SWITCH

NORM/CAL

LR403

DIP SWITCH S2

(SQUARE PORT)

POSITION l/POSITION 4

Figure 4-2:

ACCESS TO CALIBRATION CONTROLS

R404

LINEARITY ADJUST

DISTORTION ADJUST

---t

Freq

(Hz)

Table 4-l:

125 250 500

CALIBRATION REFERENCE THRESHOLDS

750

1000

1500 2000 3000

4000

6000

8000

dB 45.0 25.5 11.5 8.0

Standard Reference Threshold Levels re: 20 TDH39-P

9-A coupler.

earphones as measured on the National Bureau of Standards

Reference ANSI

7.0 6.5

S3.6-1989,

IS0 389-1975 Standards.

9.0

uPa

10.0

for

9.5

15.5

Telephonics

4.2 CALIBRATION MODE OPERATION

The

Calibration Mode is calibration. Normal

Mode

produce

the required SPL for the selected HL.

to determine the correct

This

used to

calibration information is used

perform

attenuator

the

transducer

during

position to

The

Calibration

the

Mode consists of two modes. The Custom SPL Selection Mode allows the selection of

SPL values Calibration

for

alternate

transducers.

Mode is used to calibrate the sound

The

Transducer

pressure

customized

SPL

level

(SPL) of each stimulus for each transducer.

4.2

CAL/NORMAL SWITCH

This switch is used to select the operating mode of the instrument.

switch to the CAL position while Dip Switch position.

The Calibration Mode is entered by setting this

is in the OFF

The Calibration Mode is exited by setting this switch

to the NORMAL position.

13.0

4.2.2 CALIBRATION MODE DIP SWITCHES

(See

"Calibration Mode Dip Switch In-Depth Description" later in

this section.) These

Mode.

Dip Switches select various options of

They are read to determine the selected options when

Calibration Mode is entered.

the Calibration

the

Switch

Function

OFF (down)

(up)

Default Data

OFF

Load

Loads the default Calibration data into EEPROM when the Calibration Mode is entered.

Custom SPL Mode

GSI

Custom

Enables the selection of user specified SPL values during the transducer calibration procedure when set to the Custom position.

Not used

Diagnostic Mode

N/A

OFF

N/A

Selected

Selects the Calibration Mode when the Cal/Normal Switch

is set to the Cal position if this switch is in the OFF

position.

The status of Dip Switches #4 and #1 are read only when the Calibration Mode is entered.

Dip Switch #3 is read and a change

in its position is processed if the Calibration Mode was entered

with this switch in the ON position.

Then the switch cay be

returned to the OFF position without exiting the Calibration

Mode.

-’

4.3 CALIBRATION MODE ENTRY The Calibration Mode can be entered via the Cal/Normal Switch at

any time except during the power up initialization phase or when a stimulus is being presented.

In these cases the Cal Mode will be entered when the initialization is complete or the stimulus turned off.

The indication that the instrument is in the Calibration Mode will be the non integer value in the format of xx.x on the HL Display.

During the Calibration Mode initialization process all

controls

will be inactive. When the Calibration Mode is entered,

low battery segment will be turned off.

all LCD segments except the

If Dip Switch S4 is

set

to the ON position the process of loading the default calibration

data except default data and checksum are being loaded.

will be started and the LCD display will have all

segments

the low battery segment turned on to indicate that the

When completed,

the

display will reinitialize to all segments except the low battery

segment will be off.

id'

The EEPROM will then be tested by reading the complete EEPROM to

generate

the

flashed on

a checksum which will be compared to a checksum

EEPROM.

the HL display and the initialization

If an error is found the word

"CAL

process will

stored

will be

continue.

Dip Switch #3 will be checked to determine which CAL mode is to be initialized.

If in the OFF position the transducer SPL calibration mode is selected,and if in the ON position, the Custom SPL selection mode will be selected.

4.4 MODE INITIALIZATION

When

the

transducer

SPL Calibration

Mode is

selected the

instrument will be initialized as follows:

Tone Type = Current selection

Frequency

Current selection Channel = OFF Calibration HL = 10 dB below the nonextended HL limit

for. the current transducer and frequency Transducer SPL = Calibration HL + Current RTL +10 dB

Pad = Out Transducer Routing = Current selection HL Display =Current custom SPL level stored in EEPROM Response LED = OFF Stimulus

On LED = OFF

Low Battery Segment = Current state

"+"

Segment = OFF

4.5 EARPHONE SPL CALIBRATION MODE

This Calibration Mode is used to calibrate the SPL for each

stimulus for each transducer.

This is done by adjusting the selected transducer output SPL level to the specified value displayed on the HL display.

This SPL value is the sum of the

calibration HL level and the Reference Threshold Level (RTL) for

the current transducer and frequency. standard

RTL value or

a custom RTL

The RTL may be either the

value

depending on

the

position of Dip Switch #3 when the Calibration Mode was entered.

The transducer

SPL calibration data is

stored in

EEPROM by

transducer and stimulus.

4.5

TONE TYPE SWITCH

This switch

operates as in the Normal Mode to select

Type of the stimulus.

4.5.2 ROUTING SWITCH

This

switch

operates as

in the Normal

Mode to transducer to be calibrated. All transducers must be and they can be calibrated in any sequence.

the

select

Tone

the

calibrated

4.5.3 FREQUENCY SELECTOR

This control frequency

operates as

in the Normal

Mode to

select

to be calibrated. All frequencies must be

the

calibrated

and they can be calibrated in any sequence.

4.5.4

The operates in operated

PRESENT BAR

Present Bar controls the presentation of the

a push ON/push OFF manner.

If the Present

while the stimulus is off, the stimulus will be

stimulus.

Bar is

turned

on and remain on until the Present Bar is operated a second time. The

stimulus will actually be turned ON or OFF when the

Present

Bar is pressed.

4.5.5

HL DIAL

This control performs the dual function of selecting the HL level at which the calibration is being performed and of adjusting the output level of the transducer.

While the stimulus is off,

Calibration HL level (Cal HL). up by 5

for each clockwise step of the selector and down

by 5 dB for each counter clockwise step.

the HL selector will select the

The level will be adjusted

For each change in

the Calibration HL level the transducer output level

(attenuator position) will be recalculated using the current

calibration data stored in the EEPROM.

the calibration HL will be from the nonextended

range) maximum HL limit to 20 dB below the limit.

the selector to select levels outside of this range

invalid.

When this occurs the level will default to the

The allowable range

(+10 dB

Operation

are

limit and the HL display will be flashed.

While the stimulus is on,the HL selector (dial) will adjust

the transducer output level to allow the SPL level to be

adjusted to the required SPL level on the sound level meter. The output level will be adjusted up by 0.5 dB for each clockwise step of the selector and down by 0.5 dB for each counter clockwise step. The output level is changed according to the HL selector by directly setting the attenuator position. Operation of the HL dial to select positions outside of the instrument range will be invalid. The attenuator position will be adjusted within the limits and the displayed SPL value on the HL display will be

flashed.

4.5.6 EXTENDED RANGE PUSHBUTTON

This pushbutton is used to store the transducer SPL data

stored, Response LED will be turned on for 2 seconds. data can

into

the

not be stored successfully, the word

EEPROM.

After the calibration data is

EEPROM checksum will be updated

and

If the calibration

calibration successfully the

"CAL"

Patient

will be

flashed on the HL display and the previously displayed SPL value

will

can be continued for other frequencies.

4.5.7 RESPONSE SWITCH

be restored.

If this error occurs the calibration

process

This switch Mode.

4.5.8 HL DISPLAY

4.5.9 RESPONSE LED

This LED is used to indicate the correct storage of calibration data in the EEPROM when the Extended Range Pushbutton is

operated. seconds after the calibration data has been stored and verified.

If the data is not stored correctly the LED will remain off and the word "CAL" previously displayed transducer

restored.

Operations of the switch are not processed.

This display performsthe dual function displaying the Calibration HL level and the SPL to which the transducer output level must be adjusted for correct calibration.

When the stimulus is OFF,the HL display will show the current Calibration HL level in

using digits 1, 2 and 3.

When the stimulus is ON,

required transducer output level in xxx.x the current Calibration HL and the Reference Threshold Level

(RTL) for the current transducer and frequency and does not indicate correction for the sound level meter frequency response.

using digits 1, 2, 3 and 4.

is not used during the transducer

HL in the format xx.0

the HL display will show the

This value is the sum of

This LED is normally OFF and will be turned ON for 2

will be flashed on the HL display and then the

output level SPL value will be

SPL Calibration

SPL in the format

4.5.10 STIMULUS ON LED

This LED is used to indicate the ON or OFF state of the stimulus.

While the stimulus is OFF the LED will be OFF and will be

ON while the stimulus is ON.

4.5.11 LOW BATTERY SEGMENT

This LCD segment will indicate a low battery voltage condition as

in the Normal Mode (ie:

4.5.12

This Mode and will remain off.

"+"

LCD SEGMENT

segment is not used during the transducer

LOW BAT).

SPL Calibration

turned

4.6 CALIBRATION MODE EXIT

The the calibration data is being loaded.

Calibration Mode can be exited back to the Normal Cal/Normal

Switch at

any time

In this case the

except

for when

Calibration

Mode

default

via

Mode is exited when the loading of default data is complete.

When

initialize for the Normal Mode based on the current state of

controls,

4.7 CALIBRATION DATA STORAGE AND VALIDATION

All calibration data or other data which must be the

the Calibration

as in the power up initialization.

instrument

is turned off is stored in

Mode is

exited

the

instrument

EEPROM.

retained

This data

will

the

when

consists of the following:

Transducer SPL calibration data by transducer and

frequency

Custom RTL values by transducer type

Custom RTL vs.

Attenuator

EEPROM checksum

2.5V

GSI RTL calibration selection

maximum output level limit by stimulus

The data is stored using a triple redundancy method (the same as in the GSI 16 and GSI

data bit is stored 3 times, once in each of within blocks. When location data This

the

EEPROM with a different format in

a specific data bit is required

in each of the 3 blocks is read and decoded.

to be valid the value from 2 of the 3 blocks

method will allow for the detection of data errors and

control Processor).

In this method each

different blocks

each of the

appropriate

must

the

For

match.

the the

correction of some errors. If a calibration data read error is detected the frequency which

would use the data will not be available for testing in the

Normal Mode by forcing the stimulus off and not processing operations

of the present bar.

The instrument will continue to function and all other frequencies for which no calibration data error

by displaying the word

exists will be available.

"CAL""

A data error will be

indicated

on the HL display until the frequency or transducer is changed to a new selection that has no data error.

addition to

In individual pieces of data, the the

EEPROM which will allow the validity of all data EEPROM to be determined.

the

triple redundancy validation

a 2 byte checksum will be

This check will be performed

used

for

stored in

when

the Calibration Mode is entered.

4.8

CALIBRATION MODE DIP SWITCH IN-DEPTH DESCRIPTION

The Dip Switches,

in reverse numerical order. The reason for this is that they are

located beneath the HL dial, will be

in the order in which we anticipate the frequency of usage

described

will

be.

4.8.1 DIP SWITCH S4 IF

NOTE :

DEFAULT DATA IS LOADED, DIAGNOSTIC MODE D4 PROCEDURE

MUST BE PERFORMED!

DEFAULT CALIBRATION DATA All calibration data or other data stored in the EEPROM will have

a corresponding set of default data stored in EEPROM which may be

used to initialize the EEPROM. Calibration Mode with Dip Switch

This is performed by entering the

in the ON position.

Transducer SPL calibration data: This default data is typical of transducers supplied with the

instrument.

Custom RTL values:

This default data consists of the standard GSI RTL values for the

transducer types supplied with the instrument.

Custom RTL vs.

GSI RTL selection status:

This will default to the GSI RTL selection. Attenuator 2.5 V maximum output level limit:

This will default to an attenuator limit for each stimulus. Checksum:

The

EEPROM checksum

is calculated using the

contents of

the

EEPROM after all default data has been stored.

4.8.2 DIP SWITCH S3

CUSTOM

RTL

SELECTION MODE

This mode enables selection of the displayed custom RTL values only and does not allow adjustment of the transducer's output

level.

If the user desires to use alternate transducers, this mode would normally be selected first to set the custom RTL values and the

earphone

SPL calibration would be performed.

When Calibration Mode is entered with Dip Switch #3 in position,

selection to

Dip Switch #3 can be used to switch from the custom SPL

the

transducer SPL mode while

remaining in

then

the

the ON

the

Calibration Mode.

The The RTL values for a left transducer and a right transducer

be the same.

in the RTL values.

MODE INITIALIZATION

custom RTL values are stored in EEPROM by transducer

The HL limits are directly affected by any

type.

changes

must

When

will be initialized as follows:

The level down output level (attenuator position) does not follow changes to the custom RTL value.

The Operation of the knob to select levels outside of this range will not will remain the same and will flash temporarily.

the

Tone Type= Current selection

Frequency = Current selection Channel = Off +10 dB Transducer Routing HL Display Response LED = Off

Stimulus On LED = Off

Low

SELECTOR

HL Selector is used to select the custom

by 0.5 dB for each counter clockwise step.

allowable be allowed.

Custom RTL selection mode is selected

Pad = Out

= Current selection

= Current RTL level stored in EEPROM

Battery Segment = Current state

Segment = Off

can be adjusted up by 0.5 dB for each clockwise

range of the custom RTL value is

If this occurs,the displayed custom RTL

the

RTL level.

The

+63.5

instrument

The

step

transducer

and

SPL.

value

FREQUENCY SELECTOR

Selects the frequency for which the custom RTL is to be selected.

ROUTING SWITCH

Inactive in this mode. EXTENDED RANGE PUSHBUTTON This pushbutton is used to store the custom RTL value into

EEPROM. checksum will be updated and the Patient Response LED will be

turned on for 2 seconds.

successfully, the word

and then the previously displayed RTL value will be restored. If

this error occurs,the calibration process may still be continued

for other frequencies.

After the RTL value is successfully stored the EEPROM

If the SPL value can not be stored

"CAL"

will be flashed on the HL display

DIP

SWITCH #3 OPERATION WHILE IN CAL MODE

The RTL calibration mode to the transducer SPL calibration mode.

OTHER CONTROLS All

#3,

controls will not be processed. HL The

Negative values will be displayed with a minus sign.

This LCD segment indicates a low battery voltage condition as in the Normal Mode.

PATIENT This

successfully in the EEPROM by turning on for 2 seconds.

Cal Option Dip Switch #3 is used to switch from

other controls,

are

DISPLAY

HL display is used to display the selected custom RTL

the format

BATTERYSEGMENT

inactive

xx.x.

RESPONSE

LED indicates when the custom RTL value

except the Cal/Normal Switch and Dip

during this mode.

using digits 1 through 3 of the HL

Operations of

has been stored

the

all

display.

custom

Switch

other

value

OTHER DISPLAYS

LEDs

All other

4.8.3 DIP SWITCH S2

NOT USED

4.8.4

DIAGNOSTIC MODE

The

components which

Calibration

and debugging of the board or instrument.

The

calibration mode as follows:

DIP SWITCH

Diagnostic

Hardware Diagnostic test Pushbutton Diagnostic test Display Diagnostic test A/D Diagnostic test Attenuator Maximum Output Limit calibration

and LCD segments are not used and will remain off.

Exception when in Diagnostic Mode (Dip Switch

Mode provides direct control over

Modes.

may

Mode consists of four diagnostic tests

not

This mode is provided to facilitate

be available in the Normal or

the

#1)

hardware

testing

and

one

The features of the Diagnostic Mode are controlled manually

the front panel.

from

4.9 SELECTION OF THE DIAGNOSTIC MODE

CAL/NORMAL SWITCH

This

instrument. switch the

through #4 select the diagnostic test to be performed. Diagnostic Mode is exited by setting the Cal/Normal switch back to the Normal position.

When the Diagnostic Mode is entered the functions assigned to the

CAL Option Dip Switches, (except Switch allow the selection of the desired diagnostic test.

The Dip Switches will be read only when the Calibration Mode is

entered. exit new test and then re-enter the Calibration Mode.

Switch

switch is used to

The Diagnostic

to the Cal position while Cal Option Dip Switch #1 is in

on position.

SWITCHES

To switch between diagnostic tests it is necessary to

the Calibration Mode,

Diagnostic Mode Enters the Diagnostic Mode when the Cal/Normal Switch is set to Cal.

When Dip Switch #1 is on,

Function

select

Mode is entered by setting this

reset the Dip Switches to select

the operating

Dip Switches

#1),

are redefined to

OFF (down) ON (up)

OFF

mode of

Selected

the

The

the

s2, S3, &

DO ON D1

D2 ON OFF ON

\._*--D-

(-a

ON ON DO ON ON DO ON ON ON DO ON ON ON ON

xi?+

time except selected via the switch, the initialization is complete or the stimulus turned off.

These switches are used to select the diagnostic test to be performed when the Diagnostic Mode is entered as follows: Switch Setting Diagnostic Test

s2 s3

OFF OFF OFF

OFF ON ON

Diagnostic Mode is entered via the Cal/Normal Switch at

OFF ON

OFF OFF ON

during the power up initialization phase. If

s4 OFF OFF OFF OFF

Selected Hardware Diagnostic

Pushbutton Diagnostic Display Diagnostic A/D Diagnostic Attenuator Maximum Output Level Cal Hardware Diagnostic Hardware Diagnostic Hardware Diagnostic

any

the Diagnostic Mode will be entered when

When

switched display a selected.

into

code to

the Diagnostic Mode

indicate which diagnostic

The codes are as follows:

the

HL display

test

is being

will

"DO "D1" =

"D2 "

"D4" =

The code will display for 2 seconds and then the instrument

initialize for the selected test.

= Hardware Diagnostic Test

Pushbutton Diagnostic Test = Display Diagnostic Test = A/D Diagnostic Test

Attenuator Maximum Output Level Cal

During this time all

will

controls

will be disabled.

4.9.1 HARDWARE DIAGNOSTIC TEST (DO)

TEST DESCRIPTION

This

diagnostic test provides direct and independent control of

the following hardware blocks:

Oscillator Frequency

Stimulus Multiplexer Attenuator Position +10

dB Pad Position

Transducer Routing

Each hardware block is controlled independent of all other blocks

i.e.,

selecting an

oscillator frequency will

not

change

the

attenuator position. TEST INITIALIZATION When switched into the hardware diagnostic test, the

will be initialized as follows:

Tone Type = Current Selection Frequency= Current Selection Stimulus M

= Oscillator or External input based on current

frequency knob position

Channel = OFF

Attenuator position = 255

Response LED = OFF Stimulus On LED = OFF

Low Battery Segment = Current State

Segment = OFF

TONE

This switch selects the Steady, the Normal Mode.

any used.

TYPE

SWITCH

FM or Pulsed Tone type just as in

The Steady and Pulsed Tone types will apply to

stimulus (internal

oscillator or external

The FM Tone type will always FM the internal

stimulus)

oscillator,

even if the external stimulus is selected.

instrument

being

ROUTING SWITCH This switch selects

routed just as in the Normal Mode. FREQUENCY KNOB The

frequency to 8000 Hz are selected on the knob, the internal oscillator is set for the frequency selected and the stimulus mux is set to the internal oscillator. between set to oscillator external signal of 1 V RMS can be applied to J2 on the board.

PRESENT The

operates in

(pressed and be presented a the stimulus ON or OFF.

frequency

and to control the stimulus multiplexer.

125 Hz and 8000 Hz is selected the stimulus mux will be select

will

BAR

Present

second time.

SELECTOR

Bar controls the presentation of the

released) when the stimulus is off the stimulus will

and will remain on until the Present Bar is operated

knob is used to select

the

remain at the

push on/push off manner so, if it is

The

the transducer to which

the

When the unlabeled position on

external

+10 dB

pad will not be affected by

stimulus

last

selected

input.

the

internal

stimulus is

oscillator

When 125 Hz

the

The

frequency. An

stimulus.

knob

internal

operated

turning

This position will be adjusted by step of the knob. be attenuator flashed.

EXTENDED RANGE PUSHBUTTON This pushbutton

pad.

selected the pad is in. the pad

attenuator will not be compensated for the pad position.

RESPONSE SWITCH This

all operations will be ignored.

knob is used to directly set the attenuator position.

+0.5 dB

of the knob and by

The allowable range of the attenuator position will

from 0 to 255.

position will not change and the HL display will be

When

switch is not used during the hardware diagnostic test

DISPLAY

this pushbutton is operated the

and the "+" LCD segment will turn on to

will be removed and the "+" segment

When either of these limits are

is used to control the position of the

When the pushbutton is operated a

-0.5

for each counter clockwise

(1 step) for each clockwise

reached

+10 dB

pad

indicate

second

turned

+10 dB

will be

off.

The

step

the

that

time,

The

and

This display is used to display the the attenuator

the range of 0 to 255 as selected by the HL selector.

position in

It will be

displayed in a right justified,

integer format on digits 1, 2 and

L-

RESPONSE

LED

This LED is not used during the hardware diagnostic test and will

remain OFF. STIMULUS This

LED is

presented.

used to

The

LED is

indicate

when

OFF when the

the

stimulus is

not

being being

presented and ON when it is being presented. LOW

BATTERY SEGMENT

This LCD segment indicates a low battery voltage condition.

11 + 11

SEGMENT

This LCD segment indicates the position of the

the pad is "in"

the segment will be ON and when the pad is

+10 dB

pad.

When

"Out"

the segment will be OFF.

4.9.2 PUSHBUTTON DIAGNOSTIC TEST

(D1)

TEST DESCRIPTION

This

the

operated.

display the

display.

test provides a means of testing all controls,

Cal/Normal Switch,

While in this test,

keycode

This

of the new position of the control on the HL

keycode

will be displayed until another control is

for

proper

operation

the operation of any control

when

except

manually

will

for

operated.

TEST INITIALIZATION

When switched into the pushbutton diagnostic test, the instrument

will be initialized as follows:

Tone Type = Current selection Frequency = Current selection

Stimulus M

= Current position Channel = OFF Attenuator position = 255

+10 dB Pad = Out Transducer Routing = None HL Display = Displays

"D1"

for 2 seconds and then blanks Response LED = OFF Stimulus On LED = OFF Low Battery Segment = Current state

Segment = OFF

DESCRIPTION OF CONTROLS

In this test, used to purposes.

HL DISPLAY

This operated.

LOW

BATTERY SEGMENT This LCD segment will indicate a low battery voltage condition. ALL OTHER DISPLAYS All other

will remain OFF.

Control Left

Right Pulsed FM Steady 125 Hz 250 Hz 500 Hz 750 Hz 1000 Hz 1500 Hz 2000 Hz 3000 Hz

4000 Hz

6000 Hz

8000 Hz

Freq Position Response Switch

Extended Range

Present Bar

HL Knob Dip Switch Dip Switch Dip Switch Dip Switch

select functions,

display

DISPLAYCODES FOR PUSHBUTTON/SWITCH SELECTIONS

Press Release

the controls except the Cal/Normal Switch are

but are only operated

is used to display the

The

keycode

seqments and

#1 #2 #3 #4

will display on digits 1 and 2.

LEDs

are not used during this

Key

Cod

02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18

20 21 22

23 24 25 31 32 33 34

keycodes

for

controls

not

testing

are

test and

4.9.3 DISPLAY DIAGNOSTIC TESTT

TEST DESCRIPTION

(D2)

This all

"D2 "

segments and

all

inspection

test provides a means of visually testing the operation of

LCD segments and LEDS.

will

segments and

be displayed on the HL display for

LEDs

will then be blanked for 2 seconds, after which

LEDs

will be turned on for 2 seconds to

for

any displays which

When the test is selected, the

2 seconds.

do not

turn on.

code

All

allow

All segments/LEDs will then be turned on individually for 1 second in a

left to right,

any

been

shorts between segments.

sequenced through all segments/LEDs will be turned back on

top to bottom sequence to allow for inspection

After all segments/LEDs

have

to indicate the completion of the test.

During

performed

this test the low battery voltage monitoring will not be

since the display is not available to indicate a

low

battery condition.

TEST INITIALIZATION

When

switched into the display diagnostic test,

the

instrument

will be initialized as follows:

Tone Type

= Current selection

Frequency = Current selection

Stimulus M

= Current position Channel = OFF Attenuator position = 255

+10 dB

Pad = Out

Transducer Routing = None

HL Display = Displays

"D2"

for 2 seconds and then the

display test starts Response LED = OFF Stimulus On LED = OFF Low Battery Segment = Current state

'I+r'

Segment = OFF DESCRIPTION All controls

this

diagnostic test.

CONTROLS

except the Cal/Normal switch are

ignored.

DESCRIPTION

DISPLAYS

All LCD segments and

There

are

no parameter or status information displayed on

displays.

inactive

during

Operations of all other controls will be

LEDs

are tested during this diagnostic test.

the

4.9.4 A/D CONVERTER DIAGNOSTIC TEST (D3)

TEST DESCRIPTION This test will provide a means to test the A/D converter

channel used to measure the battery voltage. When this test is selected the A/D input will be sampled every

msec

and the converted

value

displayed on the HL display. During

this test the low battery voltage monitoring will not be performed since the A/D converter is not available to measure the battery voltage.

TEST INITIALIZATION

When

switched

into

the A/D

Converter

diagnostic

test,

the

instrument will be initialized as follows:

Tone Type= Current selection Frequency

Stimulus M

= Current selection

= Current position Channel = OFF Attenuator Position = 255

+10 dB

Pad = Out

Transducer Routing = None

HL Display = Displays

"D1"

for 2 seconds and then blanks Response LED = OFF Stimulus On LED = OFF

Low Battery Segment = Current State

Segment = OFF

DESCRIPTION OF CONTROLS

All

controls

except the Cal/Normal switch

and

Extended

Pushbutton are inactive during this diagnostic test.

Operations

Range

of all other controls will be ignored. EXTENDED RANGE PUSHBUTTON This pushbutton is used to store the A/D values in the EEPROM for

"LO

Bat"

detection

"shutdown" will

occur when the battery voltage is

and

instrument

"shutdown".

too

Instrument

low to

safely operate the GSI 17 circuitry.

When the Extended Range Pushbutton is pressed the first time, the

A/D value is EEPROM.

The Patient Response LED will be turned ON and be displayed on previously displayed value can not be stored properly, the word "CAL" will be

stored as the battery low warning

the

HL display

for

2 seconds.

A/D value will be restored.

limit in the

"L1"

will

Then

If the

the A/D

flashed on the HL display and the previously displayed value will be restored.

The A/D value for battery low warning limit must be stored successfully before allowing the next press of Extended Range Pushbutton to store the battery shutdown limit.

After the

A/D value is stored properly the EEPROM checksum will be updated.

EQUIPMENT REQUIRED Variable DC power supply,

minimum DVM.

Adjust DC power supply to 7.5 Vdc then connect the negative

terminal to

Connect DVM to Audiometer Module

TP100

and the positive terminal to

operating range of

+6.5

TP1000

Vdc to

+7.5

Vdc

TP101.

(LOW) and TP102

(HIGH).

Connect simulated battery input circuit to Audiometer Module as indicated in Figure 4-3.

Power up the GSI 17. Enter Diagnostic Mode (D3).

Place Dip Switch S2 positions 1, 3, 4 to the ON

position. Place the Cal/Norm Switch to the Cal position.

The GSI 17 display will momentarily display D3, then will update to a converted A/D value.

voltage to obtain 7.30 Vdc

(+50 mV)

new A/D value in memory by pressing the Extender Button.

indicating proper important that the

The display will momentarily display

storage of data into memory.

+10 dB

button is pressed only once. If

L2 is displayed, exit Cal Mode,

Adjust the DC power supply

on the DVM.

Store the

+10 dB

Range

(It is

return to Step 5 and repeat

procedure.)

Adjust the DC power supply voltage to 7.0 Vdc

Store this A/D value into memory by pressing the

(+50 mV).

+10 dB Range Extender Button. The display will momentarily display L2 indicating proper storage of data into memory.

Adjust DC power supply to 7.5 Vdc. positions to OFF,

and place Cal/Norm Switch S6 to the Normal

Place all Dip Switch S2

Mode position.

Slowly decrease the DC power BAT indicator is displayed. and 7.35 Vdc. display should blank at 6.95 to 7.05 Vdc.

Continue decreasing the input voltage.

supply voltage until the LOW

This should occur between 7.25

The

NOTE:

To clear the LOW BA T indication the unit must be returned to full power and the power switch toggled.

After completing calibration and verification checks remove the power supply and simulated battery input circuit and proceed with calibration of transducers.

4.9.5 ATTENUATOR MAXIMUM OUTPUT LEVEL CALIBRATION (D4)

NOTE:

If Default

Data is loaded,

this procedure must be

performed before calibration of earphones.

TEST DISCR

IPTION

__-

If the Microprocessor of the GSI 17 has been replaced or a major

calibration data loss has occurred the Attenuator Maximum output

level must be calibrated.

When performing this calibration, the

operator will measure the output level on the connector

(important

-unloaded)

of the currently

adjust the attenuator position

measured.

repeated for

calibrated in any order,

The calibration data is then stored and the process is

all remaining stimuli.

but all must be calibrated.

until correct output voltage is

selected transducer

The stimuli may be

all output levels were adjusted to 2.5 vrms

frequency.

The newer GSI

levels for calibration.

17's

have specific maximum output

Serial numbers and output levels are

Originally

*.15

vrms for each

and

outlined below.

NOTE

When performing this procedure,

output must be unloaded

(no phone plugged in). SERIAL NUMBERS LESS THAN 1230 (EXCLUDING 1068, 1175r AND 1212) All frequencies 2.5 vrms

(+.15

vrms)

SERIAL NUMBERS GREATER THAN 1230 (INCLUDING 1230, 1068, 1175, AND 1212)

Frequency (Hz)

Voltage (rms) 125 250 500 750

6 K

2.30

2.15

1.90

2.50

(2.5

dB)

TEST INITIALIZATION

--___

When switched

into the

attenuator maximum

output

level

calibration the instrument will be initialized as follows:

Tone Type

= Current Selection

Frequency = Current Selection

Stimulus M

= Oscillator Position Channel = OFF Attenuator Position = 255 +10 dB

Pad = Out Transducer Routing = Current Selection HL Display = Displays

"D4"

for 2 seconds and then

"255" Response LED = OFF Stimulus On LED = OFF Low Battery Segment = Current State

"+"

Segment = OFF TONE TYPE SWITCH This switch

selects

the

tone

type.

The

calibration

would

normally be performed with Steady selected. SWITCH ROUTING

-___

This switch selects the transducer. FREQUENCY SELECTOR This

knob selects the stimulus to be calibrated.

Its

operation

is the same as in the Normal Mode.

PRESENT BAR

---- __ The

Present Bar controls the presentation of the

operates in a

stimulus.

push ON/push OFF manner so, if it is

operated

(pressed and released) when the stimulus is OFF the stimulus will

be presented and will remain ON until the Present Bar is operated

second time.

+10 dB

pad will not be affected by

turning

The

the stimulus ON or OFF.

SELECTOR

This

knob is used to directly set the attenuator position. position is adjusted by of the knob and by knob.

The

allowable range of the attenuator position from 0 to 255. attenuator

position will not change and the HL display will be

-0.5

When either of these limits

+0.5 dB

for each counter clockwise step of the

(1 step) for each clockwise

will be

are

reached

The

step

the

flashed.

EXTENDED RANGE PUSHBUTTON

------

-_-

(+10 dB

PAD)

This EEPROM. will be

properly after 3 attempts, the word HL and error

pushbutton is used to store the calibration

data in

After the calibration data is stored the EEPROM checksum

updated.

then the previously displayed value restored.

occurs

the calibration may still be continued

If the calibration data can

"CAL"

will be flashed on

not

be stored

If this

for

other

stimuli. SWITCH RESPONSE This switch

--is not used during the

attenuator

maximum

output

level calibration and all operations will be ignored. HL DISPLAY

----This

range of

displayed in a right justified,

display is used to display the attenuator position in

0 to 255 as selected by the HL selector. It

will be

integer format on digits 1, 2 and

3. LED RESPONSE This

data in operated.

seconds after the calibration data has been stored and

LED is used to indicate the correct storage of

the

EEPROM when

the

Extended

Range

Pushbutton is

This LED is normally OFF and will be turned ON for 2

calibration

verified. If the data is not stored correctly, the LED will remain OFF the

word

"CAL" will be flashed on the HL display and

then

previously displayed value will be restored.

the

and the

STIMULUS ON

LED

This LED is used to indicate stimulus presentation. The LED is

OFF when the stimulus is not being presented and on when it is

being presented. LOW

BATTERY

SEGMENT

This LCD segment indicates a low battery voltage condition.

II + 11

SEGMENT

This LCD segment will be OFF to indicate that the position of the +10 dB

pad is out.

CAUTION:

USE PROPER PRECAUTIONS WHEN HANDLING AND SERVICING.

5.1 DISASSEMBLY INSTRUCTIONS

STATIC SENSITIVE DEVICES

d. e.

(3.

j. k.

Disconnect GSI 17 from power. (Battery Pack and/or Power Module).

Disconnect and set aside all accessories. Remove 2 round control knobs, Item 1. Remove 3 slide switch caps, Item 2. Close top cover, Item 3. Turn instrument over onto its side. Open top cover.

Remove 2 screws, Item 5,

from bottom of instrument. Set instrument down. Remove 2 screws, Item 6, at back of front panel.

Lift front panel and printed circuit board, Items 7 and 8,

away from bottom case, Item 4.

Remove screw, Item 9,in back of printed circuit board.

5.2 PARTS NUMBERS

ITEM

NUMBER

1 2

DESCRIPTION

HL & Frequency Knobs Slide Switch Caps (Power, L/R,

Tone Type)

4 5 6

9 10 11 12 13 14 15

Top Cover (blank/no labels) Bottom Case (blank/no labels) #6

Screws

Screws Front Panel (blank/no labels) Printed Circuit Board

Screws Front Panel Label Frequency Dial Handswitch Power Module Back Pack Headset Assembly,

TDH-39P,

50 ohms

PART NUMBER

1717-7006

(5220-0101)

1717-7007 1717-7002

1717-7001 7044-0037 7044-0037 1717-7000 1717-4700 7044-0037 1717-0401 1717-7003 & (1717-0402) 7874-0156

(see Power Module Sec.) (see Battery Opt. Sec.)

8000-0175

5.3 ACCESSORIES & REPLACEMENT PARTS

Earphone,

Earphone Cushion, Type Headband Phone Cord Assembly (L and R) Headphone Audiocups Patch Cord, 2 Cond.

Audiogram Form, 1 pad of 50

Instruction Manual Service Manual Replacement

Label, Consult. Manual

Label,

TDH-39P,

NiCad

H.L. Recess

Pack

50 ohms

MX-41/AR

GSI 17

Label, Coverr Label, Power

AUDIOMETER

Label,

601-CLASSB2

8000-0220

VDk-

I ----

l 200 MA

8000-0046 (1 8000-0143 (1 8000-0142 4204-0147 8000-0155 4204-0505 1717-9600 1717-0100 1717-0110

8410-0060 1717-0425 1717-0426 1717-0410

1717-0415 1717-0420

ea)

Label Adjustmentt

1717-0430

DIAGNOSTIC MODE FUNCTION CONTROLS

Function controls for

Power Switch

F2 -

L/R Routing Switch

F3 - Tone Type Switch

F4 - HL Knob

the Diagnostic Mode DO are as follows:

Same as Normal Operating Mode active at all times.

This 3 position switch is active at all times in the Diagnostic Mode. Left Position to either amplifiers are disabled. Right Position

the left amplifier. Center Position - Output is routed to the right amplifier.

Same as Normal Operating Mode active at all times.

The HL knob is used to control the DAC level

indicates the current DAC level. The DAC level range of 0 to 255

along with the

allows the operator to check the

full range of the attenuator. voltages in the troubleshooting

section will be referenced to a

specific DAC level.

Output is not routed

amplifier.

Output is routed to

while the display

+10 dB

range extender

Both

All

+10 dB

Present Bar

F6A -

Stimulus on LED

F7 - Response Switch LED

Range Extender

Active at all times ON/Push OFF selection allows the

operator to change the state of the

10 dB range extender.

of LCD indicates the Range Extender

is active.

Active at all times this Push

ON/Push OFF selection allows the

operator to turn the channel OFF and

ON.

accomplished using the attenuator.

It is important to note that the

latch is updated continuously when

the Present Bar is ON otherwise the

latch is updated only when the tone

is presented.

Same as Normal Operating Mode

indicates ON or OFF state of the

Present Bar.

In the Diagnostic Mode the

handswitch is used to ENABLE/DISABLE

the Tone Oscillator.

beneficial when measuring signal to

noise.

of the Tone Oscillator.

The channel OFF/ON is

The LED indicates the status

this Push

(+)

indicator

This is

NOTE: control functions (Cal/Norm Switch, Dip Switches, etc).

Frequency Selector Active at all times - same as Normal

Refer to Calibration Mode for more in-depth description of

Mode.

6.2 OUTPUT RELATED TROUBLESHOOTING SYMPTOMS

Symptom

Output failures

Earphone Cord, Earphone, Patch Cord/Jack Panel Amplifier,

Possible Solution(s)

If applicable,

Output Routing, Amp Enable/Disable, L/R Switch, Amp Latch/Control Circuit.

GENERAL APPROACH

If the loss of output is isolated to only one of

then

try

exchanging

FAULT ISOLATION

the earphone assemblies.

the

Plug

earphones the

left

earphone into the right earphone jack and the right earphone into

the earphone, problem assembly defective, tightened securely. this left and right earphone cords, assure that the earphone numbers are legible, earphones amplifiers. the phone

left earphone jack.

then the problem is internal to the Audiometer.

remains

is at fault.

with the original earphone, then

If the earphone assembly is found to be

first check the set screws and assure that

If the screws are loose a problem similar to

would result.

If the screws are secure try exchanging if not mark the earphones accordingly.

are

calibrated

If the problem shifts to the opposite earphone

cord is defective.

If the problem shifts to

specifically to the

If the problem

left

remains

the the

opposite earphone

they

and right

with

If the

are the

serial

The

then

the

original earphone then the earphone is defective.

CIRCUIT ANALYSIS FAULT ISOLATION Refer to Audiometer Board Schematic

AT-I-EN UATOR

#3,

Section 8.

Figure 6-2:

BLOCK DIAGRAM OF AMPLIFIER SIGNAL FLOW

6.3 LEFT OR RIGHT AMPLIFIER TROUBLESHOOTING SYMPTOMS

(Refer to Figure 6-2:

ALL VOLTAGES MEASURED WITH THE CHANNEL ON, ACCORDINGLY, 1

kHz

FREQUENCY, OUTPUT LOADED.

BLOCK DIAGRAM OF AMPLIFIER SIGNAL FLOW)

L OR R SELECTED

Check for signal presence/absences at the amplifier output pin

U4 00

pin 5 - Right

U4 01

pin 5 - Left

This should be an undistorted

sinewave

of approximately 80

mvRMS.

Removing the earphone (load) should cause the output level to

increase significantly. If the

possible

signal is present here, but not at the

that

the

phone jack is at fault or an connection is missing. as

necessary.

If the signal is not present

Perform point-to-point connection

earphone it is

artwork etch

checks

here,

check

the

amplifier input pin

U4 00

pin 3 - Right

U401

pin 3 - Left

This input level should be an undistorted

approximately 80

mvRMS.

If the input signal is present here but

sinewave

not present at the amplifier output pin then the amplifier may be defective.

U4 00

U401 for a amplifier present then verify that the +5 Vdc and present.

okay,

the amplifier is most likely defective.

First check the amplifier enable line pin 1 - Right pin 1 - Left

logic 0

for

(-5 Vdc). A logic 1

muting

or to conserve power.

(+5

Vdc) disables the

If a

logic

-5 Vdc power supplies are

If amplifier enable line and power supplies check

0 is

out

If a logic 0 (-5 Vdc) is not present at the amplifier enable line

then check

U507

pin 16 - Right

U507

pin 19 - Left

for a logic 1 or

U403

Left could be defective.

(+5

Vdc).

If a logic 1 is present then

Check the power supply lines

U402

Right

accordingly.

NOTE: U403.

lines

then

The

Remove

U507

U402

U507

latch output may be loaded by a defective

U402

U403

respectfully, then recheck the control

pins 16 and 19.

U403

is defective.

If these voltages are

This type of error occurs

now

U402

correct

quite

frequently with CMOS.

CPU

LATCH

l-l510

REF

CI RCU\T

L1302

D/A

- CON’JWI’W. -

u303

OSC.OUT

u302

00X

ATTE

u301

UNEARIN

ADIllS

u300

UJuAToR

EC,

ROUTIM$

Figure 6-3:

BLOCK DIAGRAM OF ATTENUATOR SIGNAL FLOW

6.4 ATTENUATOR TROUBLESHOOTING HINTS

(Refer to Figure 6-3:

Non linearity, no output,

The VCA

(U301)

output is controlled by a dc voltage produced by

the D/A converter

controlled by the processor via the latch

BLOCK DIAGRAM OF ATTENUATOR SIGNAL FLOW)

large shifts in output level.

(U303)

The input to the

(U501).

D/A

converter is

If the from the attenuator circuit is not present at the output circuit check the following.

NOTE:

Assure

Calibration data is used to update the that the

calibration data is appropriate or

latch circuit.

Diagnostic Mode DO.

In Diagnostic Mode DO the display will indicate a DAC

255 all bits at the latch output should equal +5 Vdc attenuator clockwise

should

be at max attenuation.

Turning the HL

should cause the DAC value to decrease and the

value of

and the

level to increase. At a DAC value of 0 the latch outputs all be attenuation/maximum when the Tone Bar is ON,

low

and the

gain.

otherwise the latch is updated only when

output

should be at

(The latch is updated continuously

the tone is presented).

output

routing

select

knob

output

should

minimum

Use

the

following table to check various circuit

proper level.

voltages

for

NOTE:

Table 6-l:

Voltage measurements with DAC value of 0, 1

ATTENUATOR CIRCUIT TEST CHECK

kHz

Frequency

and Tone Steady.

Measurement Location Junction R314 & R316 (R Side) - Osc. out

U3033

DACVoltageReference

Expected Voltaqe

VRMS

3.35Vdc

Tone OFF

0 0

1.2 0 Vdc

Vdc Vdc

VRMS

U3033Pins U3022Pin U3000Pin U3000Pin

thru

4 7 7

Junction R313 &

+55

-3.4 +

R311 (R

Side) -3.4 Vdc

Vdc Vdc

Vdc

-.155Vdc

VRMS

10 dB Range Extender Check

U3000Pin

DAC DAC

Pad OUT

1.2

VRMS

Pad In

3.5

2.1

VRMS

* Sine Wave should have "clipping" evident on negative and

positive slopes.

Increasing DAC value to 5, 6, or 7 should

decrease output level and eliminate clipping.

6.5 OSCILLATOR TROUBLESHOOTING HINTS

As a

rule representatives circuitry is troubleshoot in the field using a DVM.

may be checked at specific

output pins may be checked for "relative" output level. In

the

only

test

equipment

carried by is a Digital Volt Meter (DVM). generally

difficult, if

not

Various power supply pins

IC's

on the oscillator

service

The

oscillator

impossible to

circuit

and

this

instance relative refers to an estimated voltage output dependent

on the

frequency

circuitry measures its input signal.

0 Vdc to should measure

Vdc square wave with a

2.5

indicate steady state output.

2.5

VRS would be normal and an ac reading of 0 V would steady the

state.

This type of information allows us to

presence or absence of signal flow. can sometimes point to open connections, switches,

or other hardware failures.

selected and the speed at

Generally when measuring a

Vdc.

50/50

A measurement of >4 Vdc

duty cycle the dc voltage

Likewise an ac RMS measurement of

Using this information

defective amplifiers and

which

or<1

Vdc

the

DVM's

would

indicate

check

for

The most effective way to troubleshoot the oscillator is with an oscilloscope. sinewave

or square wave.

The ocsilloscope enables visualization of the

Distortion or frequency errors become

obvious and signal level may be observed at the same time. The

#1. via

routes circuit. filtered (BP), The

oscillator circuit is located on the Analog Board The oscillator output is routed to the attenuator the

Filter

the

appropriate

Multiplexer (U 200).

signal to the input of

The

Filter

the

Multiplexer

attenuator

This signal is either the oscillator output Band

Low Pass filtered (LP), or a test

antialliasing filters round the edges of

signal

the

square

Schematic

circuitry

Pass

input.

wave

clock input prior to filtering.

If the oscillator circuit is non-functional verify that the square wave clock signal is present at

(2.5 VRMS)

indicated filter

on the front panel.

U203

square

pin -7 should be a square wave with

wave

which should be the

and its voltage swing should be approximately -3.5 V to

(2.5 VRMS). be a clean undistorted +5

Vdc (2.5 VRMS).

The output of the Switched Capacitor filter

sinewave

6.6 TROUBLESHOOTING THE PROCESSOR

U511 -

The output of

pin 10.

same

the

This is a

frequency as antialliasing

O-5

Vdc

rounded edges

+3.5

Vdc

should

with a voltage swing of -5 Vdc to

(U503)

There are some processor related problems that can be repaired in the field. combination device. converter, and a free running timer. associated as lock-ups.

The processor on the audiometer board is a

It has its own internal EEPROM, D/A

RAM, watch dog circuitry,

Priority Interrupt function,

Processor errors are generally

Lock-ups occur for various reasons. A

multi-

shorted or loaded address or data line will stop the processors

execution process, the result is a 'lock-up'.

When this occurs

the processor will generally continue to strobe the address and

data lines.

In this instance probe these lines with an

oscilloscope and look for any address or data lines that are in-

active (no data or periodic state transition).

If an in-active

line is found the processor may be at fault but the problem is

most likely a bad port or latch somewhere on the

bus.

This type of hardware failure generally requires replacement of the Audiometer Board,as this is probably the most cost effective way to resolve this type of problem.

A lock-up may also occur as the result of a defective EPROM

(U505). processor to execute. may pause or get "LOST".

This EPROM contains all the instructions for the

If there are no instructions the processor

This type of failure very seldom occurs

as these EPROMS are very stable devices.

When a new processor is

may lock-up.

There are internal system configuration registers that must be loaded by shorting the processor to ground) prior to power-up.

installed into the audiometer board it

JP1

pins 1 and 2 (Mode B pin 2 of

After power-up wait

for a period of (2 or 3 seconds) then power the unit down and

remove the jumper.

The operator/technician should then load

default data and perform self calibration (refer to Section 4,

Calibration).

It is important to note that this problem could also occur if a data error was present in the EEPROM portion of the processor.

6.7 POWER SUPPLY RELATED PROBLEMS

The GSI 17 is powered by battery or by the Power Module (Battery

Eliminator/AC Adapter). defective,

first check the power source. replaced? Were the batteries new? eliminator functioning properly? connector which attaches to the GSI

When a power supply is suspected to be

Have the batteries been

Dated?

Is the power

Is there 13 V present at the

17?

When these questions

have been answered then proceed with troubleshooting on the

Audiometer Board.

the positive terminal of Check the positive

Check for the presence of 7 Vdc to 13 Vdc at

C101

(use

terminal of

TP100

C100

for ground reference).

for +5 Vdc.

Check the

negative terminal of Cl03 for -5 Vdc. NOTE:

If any power supply voltage is incorrect the problem may

be the result of a short or load somewhere on the line.

is best to try lifting the regulator output pin

the output is

lifted pin prior to replacing the device.

correct with the pin lifted, check

If the

the power

and

measure

regulator

supply

capacitors for low impedance or a shorted device. If the operating life of the batteries appears diminished,the low

battery indicator may be improperly calibrated or the GSI 17 is

drawing excessive current. Refer to

Section 4,

Calibration, for

the battery calibration procedure.

The current draw of the GSI 17 can be checked by connecting an ammeter in place of the power switch. active mode should be less than 75 ma. In the sleep mode the current draw should be reduced to approximately 16 ma.

6.8 TROUBLESHOOTING THE DISPLAY

Refer to the Calibration Mode, Section 4, for method of entry

into the Display Diagnostic Mode

(D2).

The current draw in the

The LCD Display is relatively easy to troubleshoot. for the Display approximately 36 Hz (28 ms) with a segments of the LCD have a commonconnection via BP1 and BP2.

This Back Plane (BP) is driven continuously with a 36 Hz square

the same frequency that the segments are driven at. segments to be square wave which is

square wave. are driven with a square wave that is 0 Back Plane.

in phase there is no potential across the segment and the segment

is OFF. potential present a all times and the segment is ON.

if a segment is missing an AC meter can be used to check for proper phase relative to the Back Plane.

V would indicate the signals are out of phase and that the

segments should be illuminated.

indicate that relative to ground should indicate 2.5 VRMS. the presence of a square wave.

Vdc would indicate steady state or a possible open connection.

With this information it should be relatively easy to establish

if the driver or LCD segment is at fault.

When the two signals are out of phase there is 5 V

(U501)

illuminated (black) they must be driven with a

Any segments which are not

When the two signals present at the LCD segment are

the

sources each segment with a square wave of

180'

signals are

out of phase relative to the Back Plane

50/50

An ac measurement of 0 V would

in phase.

A dc measurement of 0 Vdc or 5

duty cycle.

oing to be illuminated

or in phase with the

An AC measurement of 5

An ac measurement

This would indicate

The driver

All

For the

Generally,

6.9 SWITCH RELATED FAILURES

Refer to the Calibration Mode, Section 4, for method of entry

into Pushbutton Diagnostic Mode

test can be used in troubleshooting all the front panel switches and dip switches independent of their Normal Mode functions. It should be relatively easy to isolate switch failures using this

mode.

The Pushbutton Diagnostic

6.10 ERROR MESSAGES

The GSI 17 will display a Diagnostic

Error Message should a

condition exist which may cause incorrect or unreliable operation

of the instrument.

an error is detected normal operation of the instrument will be aborted and the instrument will stop operating.

operator by displaying an abort code on digits

HL Display.

"Exx"

where xx is a 2 digit abort number to identify the type of

The condition of the error will be indicated to the

2, and 3 of the

The error message will be displayed in the format of

abort. When a system error

operation,

If the channel i s

All transducers will be disconnected from the channel. The Watch Dog (COP) timer and clock monitor will be

the following will occur:

occurs which causes the instrument to halt

"ON"

it will be turned OFF.

disabled.

The HL dispiay will display the error code.

The CPU will be put into a state which will halt its operation and not allow it to resume unless the power is cycled.

The system error conditions

as follows: Error Code E01

Probable Cause EPROM FAILURE

error at power up. If not recoverable replace

U505

replacing

open traces,

then

U503

U505

or shorted traces between

U503.

to be tested for and their codes are

and Solution

Indicates the EPROM checksum was in

If the problem is not resolved by

U503

then check for Buss loading,

U505

and

E02 E03

E04

E05

E06

RAM FAILURE

WATCH DOG TIMER ERROR

If not recoverable replace

U503.

U503

CPU CLOCK FAILURE

If not recoverable replace

U503. UNDEFINED INTERRUPT ERROR - If not recoverable

replace

OPCODE TRAP ERROR

then

U503

U505.

then

U505.

If not recoverable replace

U503

54A

Error Code

Probable Cause and Solution

E07

E08

E09

E10

E11

INVALID TONE SWITCH SETTING - If not recoverable replace S5 then

INVALID FREQUENCY SWITCH SETTING - If not recoverable replace RE2 then

INVALID ROUTING SWITCH SETTING - If not recoverable replace S4 then

UNDEFINED KEY CODE ERROR with the failure of any front panel control. If not recoverable replace

CONFIGURATION REGISTER ERROR - The processors internal registers are not properly configured.

With the power switch OFF install a temporary

jumper wire (short) across

place the power switch in the ON position and wait

for approximately 10 seconds. registers should now be properly configured.

Return the power switch to the OFF position and

remove the jumper wire. exists replace the processor above procedure.

U503.

This error may occur

U503

then

JP1

If the problem still

U505.

pins 1 and 2.

The processor's

U503

and repeat

Then

the

El2

E20

E21

E22

E23

E24

LOW VOLTAGE ERROR adjustment is not set to within the acceptable

range.

Down Calibration (Calibration Section 4.9.4). If the problem still exists replace procedure.

CALIBRATION DATA READ ERROR - If not recoverable replace

HL LIMIT EXCEEDED U503.

INVALID EXTENDED RANGE SELECTION - If not recoverable the problem may be related to

U506, U508 CALIBRATION DATA WRITE ERROR - Should occur only in

the Calibration Mode.

recoverable replace

INVALID PRESENT BAR DUE TO CALIBRATION ERROR

Should occur only in the Calibration Mode.

recoverable replace

If not recoverable perform Battery Low/Shut

U503.

NOTE:

Re-cal may clear.

U503.

Battery Low/Shut Down

U503

and repeat

Re-cal may clear.

If not recoverable replace

U509,

If failure is not

If not

E25

ERROR PERTAINS TO FACTORY CALIBRATION PORT

recoverable replace

U503.

54B

If not

Error Code

Probable Cause and Solution

E26

E27

E28 & E29

E31

E32

E33

EEPROM CHECKSUM ERROR

is in error. If not recoverable perform calibration. If the problem is not resolved by calibration replace

EPROM TO EEPROM DATA LOAD ERROR - If not

recoverable replace CALIBRATION TYPE READ ERROR - Should occur only

upon entry to Calibration Mode. the problem may be related to U506,

BATTERY SHUT DOWN LEVEL READ ERROR - If not recoverable perform Battery Low/Shut Down Calibration (Calibration Section 4.9.4). problem persists replace

BATTERY WARNING LEVEL READ ERROR - If not recoverable perform Battery Low/Shut Down

Calibration (Calibration Section 4.9.4). If problem persists replace

STACK OVERFLOW ERROR - Should always be

recoverable.

U505.

U503.

If the error persists replace

U503.

U503

then

Data in the Mirror Memory

U505.

If not recoverable

S2, S6, U509, U508,

If the

U503.

U503

E34

E35

E36

E37

E38

E39

BAD POINTER TO EEPROM ROUTINES - If not recoverable replace

INVALID KEY CODE ERROR U505

then

INVALID KEY SOURCE ERROR - If not recoverable replace

INVALID QUEUE POINTER ERROR - If not recoverable replace

BATTERY VALUE OUT OF RANGE - If not recoverable perform Battery Low/Shut Down Calibration

(Calibration Section 4.9.4).

replace

ERROR PERTAINS TO FACTORY CALIBRATION PORT

recoverable replace

U505

U503.

U505

U503.

then

U503.

If not recoverable replace

If problem persists

If not

54c

7.1 ANALOG CIRCUIT

A square wave at the desired frequency is generated by a

internal

to the microprocessor.

This square wave is applied to

timer

the input of switched capacitor filters for smoothing into a sine wave.

frequencies Since

The filter

except

section is programmed as Low

KHz where it is configured for

Pass

there are two filter output configurations, a

for

Band

all

Pass.

multiplexer

(switch) is used to route the sine wave to the attenuator block.

The

resolution

DAC,

Normal used only for calibration purposes in the Calibration Mode. total

required to

attenuator

by an 8 bit Digital to Analog Converter

is a voltage controlled amplifier set to

.5 dB

(DAC).

which is processor driven, controls the attenuator in

Mode at a resolution of 5.0

dynamic range of the attenuator is 112

provide

the Normal Mode HL range as

dB.

The.5 dB resolution is

dB.

This range is

well as

The

the

The

the

overhead dB range required for calibration per frequency. Following

Range extension is accomplished by increasing the gain of the Amp,

which is

the

sourced

attenuator

by the attenuator, by 10

is a

=10 dB

range

dB.

extension

block.

OP-

The range extender circuit applies the pure tone sine wave to the

input of

signal

never

power amplifiers, in turn,

the output routing switches.

The switches

apply

the

to either the left or right power amplifier, however, it

applied to both simultaneously.

The

left and

right

drive the left and right earphones.

7.2 DIGITAL CIRCUIT

The microcomputer. power consumption. bit programmable I/O ports,

(A/D),

Counter/Timer,

very few external

external EPROM

heart of

the

digital

circuitry is a MC

68HC11A1

This CPU was chosen for its flexibility and

Functions available from the device are (5) 8

an 8 bit analog to digital

K Bytes of ROM, 256 Bytes of RAM, 512 Bytes of EEPROM,

and Serial Port Interface.

support devices required.

As a result, there are

If there is an

(32 K Bytes), a programmable

converter

timer,

low

and

miscellaneous decodes, line multiplex, etc. The

instructions conjunction pertinent

parameters

clock

instructions,

analog

CPU executes the commands stored in ROM and

are

with

the

result of a

front

panel

look-up tables, and such,

for

calibration data for the selected parameters.

could be:

frequencies for the switched capacitor

HL calibration for a

specific

filters,

or as simple as an ON/OFF command to a CMOS switch.

summary,

and

the digital circuitry in the GSI

17 controls

display circuitry in such a manner

EPROM.

command in

applying

frequency,

that

the

These

the

Such

display

the

front

panel selections are processed and acted upon accordingly.

8.1 GENERAL NOTES

The Audiometer Board is a self-contained audiometric module.

If the board is changed,

the headphones must be calibrated

to the board.

If during the calibration process,

default data is loaded then diagnostic mode D5 procedure must be performed (see Section 4, Calibration of this manual).

If the micro controller or audiometer board is changed then

default data,

and Diagnostic Mode D5 procedure must be

performed.

8.2 MICROCOMPUTER

The

MC68HC11A1

is an 8 bit MCU with sophisticated on-chip

(U503)

peripheral capabilities. In the GSI 17's application it operates at a nominal 1 MHz bus speed. smaller size and higher speeds with the low.power and high

immunity of

CMOS.

On-chip memory

The HCMOS technology used combines

noise

includes

512 bytes of

electrically erasable programmable ROM (EEPROM) and 256 bytes of

random-access

memory (RAM).

The on-chip peripheral

functions

include:

Eight channel analog to digital (A/D) converter with eight

bit resolution of which two channels (PE6 and PE7) are used to monitor battery functions.

Free-running timer system that has three input capture

lines.

Two lines

(PAO

and

PA1)

are used to decode HL direction and amount of change on an edge triggered basis. The third input capture line (PA2) is used to detect left

right output selection.

vs.

A real time interrupt function (XIRQ) which is used by the

Present Bar for immediate processing of a "Present" command.

Self-monitoring circuitry is

against system errors.

This

included on-chip to protect

"computer operating properly"

(COP) watch dog system protects against software failures.

The internal 512 byte EEPROM contains data for the A/D

relative

battery level below usable level threshold.

to the

"LO

BAT"

(Low Battery) threshold and

Also

converter

"DEAD BAT"

stored in the EEPROM are all calibration HL, SPL and attenuator data. data is method

each calibration point per frequency is stored

stored

with a triple redundancy

technique. In

3 times,

This this

once in calibration point is requested, of the valid calibration error is detected,

each of 3 different blocks within the EEPROM.

the appropriate location in

three blocks is read and decoded.

the

value

from 2 of the 3 blocks must

For the data to be

match.

the frequency and transducer which

When a

each

If a

would use the data will not be available for testing by virtue of the

function for

channel being forced off.

all combinations of

which have valid calibration data.

The instrument will

frequencies and transducers

This memory retains its

continue to

data

even when power is not applied to the device.

The capacity. functions as adding HL dial to transducer RTL for a given setting.

internal 256 bytes of RAM is used in a

It's

used

as a temporary storage

medium for

This memory can only retain data when it

"scratch-pad"

such

output

has power

applied to it.

8.3 EPROM The

K byte by 8 bit EPROM contains the operating

for

the GSI

and executes the instructions accordingly.

U505)

17.

instructions

The microcomputer fetches data from

The instructions

the

EPROM

for the Normal calibration and diagnostic modes are contained in this memory.

EPROM is non-volatile memory, meaning that data

storage

is not lost when power is removed from the device.

8.4 TIMER

There is a programmable timer chip which is used for 3

functions

(U511)

via 3 programmable outputs.

different

One output is the

square

wave (SQWIN) which ultimately gets filtered into the pure tone

used for presentation into the earphones.

clock (SCFCLK) points. output

selected.

These first two outputs (SQWIN, SCFCLK)

frequencies dependent upon the

The third output is a set pulse train which

negative-going .2 used pulse every 2

for setting the switched capacitor filter

msec pulses are used as an interrupt for the processor so that it update

the COP circuit and perform the polling of the status of

A second output is the

have

front panel

variable

frequency

sends a

the CPU.

These

can

the controls not previously mentioned.

8.5 POLLED CONTROLS

The majority of controls are read via a polling technique.

is, determined rates of time. at a rate of 12 msec. status, status stated bounce time (settling time) every 12 msec.

the

CPU reads

the status of

each

key/control at

The polling in the GSI 17 takes

then

msec

Every 12 if that control is determined to be in later,

it is acted upon.

msec

a control is "looked

Therefore it

that the following controls are polled and allowed a

The keys/controls

the same

That pre-

place

at"

for

can be

de-

as follows:

The HL Knob The Frequency Dial The

=10 dB

Extended Range Key

are

The Left/Right Control The FM/Pulsed/Steady Control The Subject Response Switch

The Calibration/Normal Mode Switch

The Calibration/Diagnostic Mode Dip Switch(s)

8.6 INPUT/OUTPUT (I/O) PORT DESIGNATIONS

Physical Signal

Port

Bit

Name

Direction

Description

U503

PORT(A)

6 7

HL1 HL2

LEFT

SPARE

+10 dB

SPARE OUT UNUSED

IN IN

N/A N/A

OUT

HL1

and HL2 form a 2 bit code of the HL selector position.

HL2 Position 1 - 1 Position 2 - 1 Position 3 - 0 Position 4 - 0

LEFT and UNUSED form the 2 bit code of the Routing

Switch position.

UNUSED LEFT

Invalid - 0

Unused - 0 Right - 1 Left

Not Used Not Used +10 dB Pad control. 0 = Pad Out

Not Used See Bit 2 - LEFT

(Extended Range)

-1

HL1

1 0 0 1

0 1 0 1

1 = Pad In

(Range

Extended)

U503

PORT(E) 3

FREQ1 2 1 0

FREQ2

FREQ3

FREQ4

IN IN IN IN

SELECT FREQ FREQ4 FREQ3 FREQ2 12525

250

Hz-

500

Hz-

750

Hz-

KHz-

1.5KHz-

KHz-

Pos.12-

FREQ1-FREQ4 code of the Frequency Selector position.

LSB

1 1 1 1 0 1 1 1 1 1 1 1 0 0 0 0 1 0 0 0 0 0

form the 4 bit

1 1 0 0 0 0

0 0 0

0 0

1 1

0 0

1 0 1 1 1 1

MSB

FREQ1

1 1

0 1

Physical

Port

Bit Name

Signal

Direction

Description

U503

PORT(E) 4

U503

PORT(D) 6

U503

PORT(D) 0

PULSE

PULSE and FM form the 2

bit code of the Tone Type

switch position.

PULSE

;

BAT/LINE

Invalid - 0 FM Pulsed

-0

Steady - 1

Voltage Source Status

0=lINE

Voltage

l=Battery Voltage

BATVOLT

Analog Battery Voltage

input to the A/D converter

RXD 1 2 3 4

TXD

MISO

MISI

SCK

IN OUT IN OUT OUT

SCI Received Data SCI Transmitted Data SPI Input - Not Used SPI Data to Display Driver SPI Clock to Display

Driver

SLEEP

OUT

Sleep Mode Status

O=Awake 1+In

Sleep Mode

6 7

N/A

N/A N/A

U509

DIAG

SPARE ALTREF

DEFAULT

RANGEX

SUBRES

CAL

Dip Switch #1 -

Diag/Cal

Mode

O=ON =Enter Diag Mode l=OFF=Enter Cal Mode

Dip Switch #2 - Spare

Dip Switch #3

-GSI/User

SPL

O=ON 1=OFF=GSI

=User

SPL Mode

SPL Mode Dip Switch #4 - Default Data

O=ON 1+OFF=Do

=Load

Default Data

Not Load Data

Extended Range Switch

Status

0=Pressed

1=Relaesed Subject Response Switch Status

0=Pressed

1=Released

Cal/Normal Mode Switch Status

O=Calibration Mode

l=Normal Mode

Physical Port

j3&

Signal

Name Direction Description

PRESENT

Present Bar Status

0=Pressed 1=Released

AFILHI

50/100

BP/LP

EXTIN

PRESLED

SUBLED

RON

LON

OUT

Oscillator Antialiasing Filter Select

AFILHI 125 Hz - 0 0 250 Hz

- 0 0

500 Hz - 0 750 Hz - 0 1 KHz

1.5KHz 2 KHz 3 KHz

1 0 0 1

1 0 0

50/100 BP/LP

0 0

4 KHz -1 1 0 6 KHz

8 KHz -- 1 1 1

Oscillator Clock Scale

Select (see AFILHI for States)

Oscillator Digital Filter Type Select (see AFILHI

for States)

External Input MUX control

0=Select 1=Select

External Input. Oscillator

Channel ON LED Control

0=LED 1=LED

OFF

Response LED Control

0=LED 1=LED

OFF

ON Right Channel Routing Control

0=Channel 1=Channel

OFF

ON Left Channel Routing Control

O=Channel OFF

l=Channel ON

u510

DACO DAC1 DAC2 DAC3 DAC4

DAC5

DAC6 DAC7

OUT OUT OUT OUT OUT OUT OUT OUT

Attenuator DAC

Level

Control. 0 ->255

U511

Timer

Signal

Name Direction Description TMRO TMR1 SCFCLK TMR2

Front Panel/ Freq

125 250 500

750 909.09 90,909 1000 1176.47 117,647 34.00 1500 1818.18 2000 2500.00 3000 3333.33 4000 5000.00 6000 8000 8000.00

Filter Cutoff Freq

150.38

300.75

606.06 60,606

8000.00 400,000

SQWIN

CLKGEN

SWITCHED CAPACITOR FILTER CONTROLS Switched

Capacitor SCFCLK (Clock) Freq

15,038 30,075

181,818 250,000 333,333 250,000

400,000

OUT OUT Clock. OUT

Timer Setting

266.00

133.00

10.00

8254 Counter 0 Used for the Oscillator SWQIN

Stimulus Frequency 8254 Counter 1 Used for the Oscillator Switched Capacitor Filter SCFCLK.

(see the following table

8254 Counter 2 Used to Produce the 2 base.

50/100

State

66.00

44.00

22.00

16.00

12.00

16.00

Frequency =

msec Time-

Antialiasing AAFIL State

0 0 0 0 0 0

0 0 1 1 1

BP/ LP

0 0 0 0 1 1

1 1 1

0 0 0 0 0 0 0 0 0 0 1

-1

8.7 DISPLAY (LCD)

The LCD is a reflective is the largest indicator on the GSI 17, and it is used for a

variety of purposes.

possible error messages in the Normal Mode, along with SPL and

A/D numbers in the calibration and Diagnostic Modes.

each mode's functional description for detail).

An LCD segment is energized only when there is a 5 Volt potential across it. drive signal,

signal and CH2 to the segment drive signal. the across it.

signals should be out of phase, therefore applying

To confirm if a segment is receiving the

connect

3-1/2

Some purposes are:

CH1

digit Liquid Crystal Display. It

of an oscilloscope to

indication of HL and

(Refer to

appropriate

the

For an

backplane

"ON"

5 Volts

segment

6666

8.8 OUTPUT ROUTING AND POWER AMPLIFIERS

Analog

and possibly range extended, amplifiers.

switches

The

U402

and

U403

CPU reads

are used to route the

attenuated,

signal to the left and right

the

status of

the

front

power panel

left/right switch and controls the analog switches accordingly.

The

ability to cross-channel approximately 1 watt, This is a very important feature for use under battery power.

series

use of

two power amplifiers

turn

them off (Pin 1) minimized

leakage.

The

amplifiers,

(U400, U401)

which

the

can be turned off for minimal current draw.

130 ohm resistor at their output serves as an

well as

the potential of can

deliver

attenuator

for both signal and noise when the 60 ohm phones are connected.

8.9 POWER SUPPLY

The on-board power supplies consist of a +5 Volt regulator, -5 Volt regulator and a voltage converter.

whether it be from a battery or approximately +7 Vdc.

U102,

Volt regulator. analog and digital circuits. applied to converter circuitry,

is inverted to -7 Volts.

This positive voltage is applied to the

The positive 5 Volts supplies both the

The unregulated +7 Volts is also

U101

where,

a battery eliminator, is

through its switched capacitor

The unregulated negative

voltage is then applied to the -5 Volt regulator

The input supply,

U100.

Note that

the voltage converter is disabled (shutdown) whenever the sleep

mode is entered.

through

U202.

This is accomplished via controls switched

8.10 OSCILLATOR

The

oscillator is

comprised of the following

IC's

and

their

functions:

U203 -

U202 U201 -

U200

U203

takes

front panel selected frequency and converts it to a +5 V

This

signal is antialiasing eliminate high freqeuncy harmonics. applied to

level shifter

antialiasing filter

programmable switched capacitor filter

Low Pass/Band Pass selector

the 0 to 5 Volt sqaure wave (from

then applied to the

filter

"rounds"

the edges of

antialiasing

The

output of this filter is

the input of switched capacitor

U511.10)

the sine filter

the

signal.

filter. An

wave to

U201.

The switched capacitor filter is programmed via clock frequencies and the

state of the

50/100

line.

found at the end of the I/O port designation listing (see

U201

(from

U507

controls can be

U507).

The switched capacitor filter is set to a Low Pass configuration

for

all frequencies except 8 KHz where it is set for Band

Pass. This filter reduces harmonics and any other noises resulting in a clean sine wave product.

8.11 ATTENUATOR AND 10 dB RANGE EXTENDER

The attenuator

(U301)

is a voltage controlled amplifier.

Although it does have amplification gain, the majority of its

dynamic range is used as an attenuator.

The total range of the attenuator is 112 dB which is adjustable using a variable dc voltage applied to Pin 3 (EC) of the device. operating mode,the attenuator is set to 5 dB resolution. calibration mode,

however,

0.5 dB resolution is available and

In the normal

In the

made possible by an 8 bit digital-to-analog converter (DAC).

Earphone calibration is accomplished by storing an HL to SPL value per frequency in a look-up table in EEPROM.

For example,

at 1 KHz and 80 dB HL the CPU will set the attenuator to a

position which will establish 87 Therefore,it can be stated,

that the attenuator for a given

SPL in either earphone.

frequency is offset from the nominal indicated HL by a decibel

value equal to the Reference Threshold Value

resolution of

The

switchable

amplifier

feedback resistor. This stage serves as the

dB.

stage

(U300)

following the attenuator has a

range extender circuit used during normal operation. the stage is changed by switching Resistor R304 in parallel R303

or grounding R304 at one end

(+10 dB

position).

(RTV) to a

+10 dB

The gain of

with

8.12 POTENTIOMETER ADJUSTMENT PROCEDURES

LINEARITY ADJUST

Set front panel controls to: 1 KHz, 80 HL, Tone Steady,

()

Channel ON.

Set a reference on Sound Level Meter (SLM) with either left or right earphone coupled to it.

Reduce HL dial to 60 HL and note reading on SLM.

Adjust R404 for a obtained in step

-20 dB change from the reference level

"b".

Re-check 80 HL for 20 dB change,

II. DISTORTION ADJUST (R403)

NOTE:

TP100

Tone may be locked

"ON" in the Normal Mode by connecting

to the cathode of CR3.

Set front panel controls to:

activated),

Tone Steady, Channel ON.

Connect a distortion analyzer to either left or right phone output,

load with 60 ohms and select the appropriate output

using the front panel switch.

readjust R404 as necessary.

1 KHz,90 HL

(+10 dB

Adjust R403 for minimum distortion.

should be less than 2% (THD).

Minimum distortion

Check distortion at opposite earphone jack.

NOTE : 2%,

remove 60 ohm load and recheck.

If distortion at output cannot be adjusted to

amplifiers may be at fault, if not,

8.13 SUGGESTED REPAIR PARTS 1717-4700ROT

Audiometer Board Rotating Stock 1717-9610 Parts Kit Note:

Qty

1 1 1 1

1 1 2 1 1

The following parts are included in this kit.

GSI Part Number Description 7874-0173

7874-0172 7874-0171 7874-0175 7874-0170 5437-1275 1717-3810 4214-0155 4204-0147 1717-9610-AS

Slide Switch (Power, L/R, Tone Type) HL Switch

Frequency Switch

Cal/Norm Switch

4 Position Dip Switch LCD LCD Fixture

Phone Jacks Earphone Cord

1717 LCD Installation Procedure/Parts Kit

If distortion

less

reduces, power

than

attenuator may be the cause.

8.14 AUDIOMETER BOARD PARTS LIST

1717-2700 (3)

\-_

Ref Designation Description

INTEGRATED CIRCUITS

U100 U101 U102 U200 U201 U202 U203 U300 U301 U302 U303 U400 and U402

and

U401 U403

U500

U501

U503

U504

U506 U507 U508 U509 U510 U511

IC, Lin., IC,

LT105A, IC, Lin., IC,

MC14052B,

MF10,,

IC, IC,

MC14053B,

MC79L05,

Volt. Converter/Reg. LM2931, +5V

Dual Filter

IC, LT1013, Dual Op. Amp. See

U203

IC, DBX2155, VC Amp. See

U203

IC, AD7523, IC, MC34119, Low Pwr. Audio. Amp.

See

U202 IC, IC, IC, IC,

IC, IC, IC, IC,

See

IC,

MC34064,

H0438A,

MC68HC11A1, 74HC00, 74HC138, 74HC273, 74HC373, 74HC244, U507 82C54,

Undervoltage Sensor

Serial LCD Driver

Quad. 2 Input Nand.

1 of 8 Decode/Demux Octal D Flip Flop Tri State Octal Latch

Octal Buffer/Driver

Prog. Timer

-5V Reg. Reg.

Dual Chan. Mltplx. Tri 2 Chan. Mux/Demux

8 Bit D/A Conv.

8 Bit

MicroContr.

Part No.

5432-1151 5432-1152 5432-1150 5431-7027 5432-1091 5431-7054 5432-1050

5432-1092

5432-7003 5432-1120

5432-1117 5433-1020 5431-9017 5431-3000 5431-3138 5431-3273 5431-3373 5431-3244

5431-9012

DIODES

CR1 and CR2 CR3 CR5 CR100* CR101 CR102 CR500

RESISTORS AND POTENTIOMETERS

R100* R200

R201 R202 R203 R204 R205 R206 R207 R208

and R209 R210 R211 R300

LED, HLMP-0504, Green, Square Diode, See CR3 Diode, Zener, Diode, Diode, See CR3

Res., Film, Res., Film, Res., Film,

See R200 Res., Film, See R200 Res., Film, Res., Film,

See R200 Res., Film, Res., Film, See R200

Res., Film,

1N4151

1N4004

1N5817

SA11A

10 Ohm,

10K, 1/4W,

1/4W,

3.57K, 1/4W,

4.22K, 1/4W,

30.1K,

1/4W,

10.7K, 1/4W,

6.19K, 1/4W, 200K, 1/4W,

39.2K, 1/4W,

1% 1% 1% 1%

1% 1%

6084-1206 6082-1001

6083-1100

6081-1002

6084-1017

6350-9100 6350-2100

6350-1357 6350-1422 6350-2301

6350-2107 6350-1619

6350-3200

6350-2392

*See Section 9, Power Module for update.

Ref.

Desiqnatio

Description

Part No.

RESISTORS

R301 R302 R303 R304 R305 R306 R307 R308 R309 R310 R311 R312 R313 R314 R315 R316 R317 R400

and R401 R402 R403 R404 R500 R501 R502

R503

R504 R505

and R506 R507 R508 R509

and

R511

R512

R515

thru R517

AND

POTENTIOMETERS

R510

Res., Film,

Res., Film, Res., Film, Res., Film, Res., Film, Res., Film,

5.23K, 1/4W,

49.9 Ohm, 20K, 1/4W,

9.09K, 1/4W, 3930 PPM,

4.02K 1/4W,

150 Ohm, See R302 Res., Film, Res., Film, Res., Film, See

R303

Res., Film,

100 Ohm,

49.9K, 1/4W,

27.4K, 1/4W,

3.32K, 1/4W,

1K, 1/4W, See R300 See R304

Res., Film, Res., Film,

90.9K, 1/4W,

130 Ohm, See R200 Pot., Comp., Pot., Comp., See R200 See

R314 Res., Film, See

R314

332 Ohm,

Res., Comp., See R314 Res., Film,

499 Ohm,

Res., Comp.,

See R310

Res., Film,

24.3K, 1/4W,

See R314

See R502

1/4W, 1/4W,

1/4W,

50K, 20%, 1K, 10%,

25 Turn

1/4W,

47K,

1/4W,

10M, 1/4W,

1/4W,

1.0K, 1%

1% 1%

6350-1523 6350-9499 6350-2200 6350-1909 6700-0002 6350-1402 6350-0150

6350-0100

6350-2499 6350-2274

6350-1332 6350-1100

6350-2909

6350-0130

6049-0350 6049-0500

6350-0332

6099-3475

6350-0499

6099-6105 6350-2243

RPSOO RP501 RP502 RP503 RP504

RP505

CAPACITORS

Cl00 C101 C102 C103 C104 C105 C106 C200

and

C201

Res., Res.,

Network, 47K x 9, Network,

10K

x 9, See RPSOO See

RP501 See RPSOO Res.,

Cap., Tant., Cap., Tant., 4.7

Cap., Cer., 0.1 Cap.,

Cap., Cer.,

Network,

Elect.,

4.7

.01 uF, -20%, +80%, 50V

100K

x 8,

uF 20%,

uF, 20%, 50V

uF,

208,

Cap., Tant., 100 uF, 16V Cap., Tant., 10 See

C104

uF,

208, 6v

+2%

22%

+2%

16V

10V

6740-1747 6740-1712

6740-1710

4450-4520 4450-4990 4400-3000 4450-4700 4400-3003 4450-4515 4450-5100

Ref. Desiqnation Description

Part No.

CAPACITORS C202

and C204 C205 C206 C207 C208

thru C211 C300

and C302 C303 C304

and C306 C307

thru C311 C400

thru C404

and C406

and C408

and C410 C411 C412 C500

C501

thru

C505

C506

C507 C508 C510 C511

thru C517 C518 c519

C203

C210

C301

C305

C310

C403 C405 C407 C409

C503

See

C102 Cap., Cer., Cap., Cer., Cap., Cer., Cap., Cer., See

C102 See

C205 See

C102

.0047 Uf, 5%, .001 uF, 5%,

.01 uF, 20%,

0.047

Cap., Cer., 68

Cap., Cer., See

C103 Cap.,

See See See See See See See See

See

Cer., C102 C306 C104 C102 C104 C102 C104 C306 C104

1.0

0.47

Cap., Cer., 47 See

C104

See

C102

Cap., Cer., 22 Cap., Cer., 10 See

C102

See

C1303

See

C102

See

C303

See

C205

50V

50v

uF, 5%,

50V

pF, 10%, 100V

uF, +20%, -80%, 50V

uF,

-20%

+80%,

5ov

pF, 10%, 100V

pF, 10%, 100V pF, 10%, 100V

4400-3010 4400-3008 4400-3004 4400-3009

4400-3007

4400-3002

4400-3001

4400-3006

4400-2022 4400-3005

SOCKETS

XU503 XU505

MISCELLANEOUS

J1 J4 and J5 J7 J8 LCD1 RE1

RE2

s2 s3 S6

Socket,IC, 28 Contact Socket, PLCC., 52 Contact

Conn., Jack,

See

Pow. Input, 5 Pin, Din Socket

Earphone & Handswitch, PC

Mtg.

J4 Conn., 6 Pin, Female, Telephone Display, HL Encoder,

LCD, 3.5 Digit

2-Bit Rotary

Frequency Encoder, 4-Bit Rotary

Switch Dip, 4 Position Switch, Switch,

Present/Ext. Cal/Norm,

Range Switch

DPDT, Rt. Angle

7540-1828 7540-1852

4230-4025 4214-0155

4230-4030 5437-1275 7874-0172 7874-0171 7874-0170 1717-0400 7874-0175

Ref. Desisnation MISCELLANEOUS

Description

Part No.

No.

SHIELD 1

SHIELD 2

SHIELD 3 TP100 U505 Y500 DBL Pole, 3 Pos.

thru TP102

ESD Director, LCD, ESD Director, LCD, 0.83" H. ESD Shield, Switch, Jumper,

EPROM, Programmed

Crystal, 4 MHz, Low Profile Switch, Steady/Pulse) Spacer, LED

Insulator, Crystal

Test Point

Slide (ON/OFF, L/R, FM/

.83"

.45"

1717-8005

1717-8005 1717-8010 5080-0001 1717-0500 5075-0045

7874-0173 7574-0205

7574-0210

10.1 DESCRIPTION

The GSI 17 can be operated via battery power with the 1717-2010 battery option.

supplied rechargeable available size C alkaline batteries.

illustration of the battery pack).

This battery pack can be used with the

NiCad

pack (8410-0060) or with commercially

NOTE:

(See Figure

10-3

GSI-

for an

In no

affect instrument calibration.

10.2 BATTERY PACK INSTALLATION

If your pack is already installed in the instrument and you can disregard this section.

If the GSI 17 battery pack has been purchased separately from the audiometer,

there are four (4) screws included with your battery pack option. They will be used to mount the pack into the storage cavity of the audiometer. close to one side, are four sections of the case which must be punctured to provide entry holes for the four screws.

Before installing the battery pack, turned off and unplugged from the AC power (mains) outlet. Unplug the power cord, used) from the back panel of the audiometer. from the instrument. cover and place the instrument on a flat surface. Proceed as follows:

audiometer was purchased with the battery

it must be installed into the instrument.

instance will loss of

On the bottom of the storage cavity, located

(4) indentations.

(See Figure 10-l).

the earphone jacks and the handswitch (if For greatest convenience, remove the top

battery power

option,

Note that

These are thin

be sure the instrument is

Remove these items

the

a.b.Using a Phillips head screw driver, gently apply

pressure to the four indentations, one at a time, to puncture the case for the screw entry holes. the screw driver will help achieve the correct hole size.

Turn the instrument on its side. pack,

while inserting the mounting screws. screws.

you will need to hold it in the storage cavity

To attach the battery

Secure all four

Turning

Figure

10-2 :

BATTERY POWER CONNECTION

Connect the battery pack power cord (A) to the power cord receptacle on

the rear panel of the audiometer.

For line power operation (mains) or recharging, connect

the instrument power cord (B) to the receptacle on the lower edge of the battery pack (perpendicular to the instrument rear panel).

(See Figure 10-2).

10.3 NiCad BATTERY OPERATION

The GSI 17 battery option is supplied with an installed,

rechargeable NiCad battery pack. fully charge,

operation.

and will provide about 22 hours of continuous

The green LED on the pack itself will be lit when

It requires about 18 hours to

charging is in progress. The words LO BAT will be illuminated on

the front panel LCD when the battery charge is getting low so the

operator will know when to recharge the batteries.

is lit,

the instrument will operate (continuously) for about two

When LO BAT

hours before it shuts down completely.

NOTE:

In no instance will loss of battery power

affect instrument calibration.

CAUTION:

Although no damage to the rechargeable NiCad batteries will occur if the pack is left

charging for more than the 18 hours required for a full charge, left charging for extended periods

the batteries should not be

(i.e. several days) because the useful life of the rechargeable NiCad pack will be shortened.

Lucas GSI recommends unplugging the battery pack power input cord from the rear of the audiometer and plugging the main line power cord into this jack if main line power is to be used most of the time.

save battery life,

To which

the

operation.

audiometer will

The

operator will know the instrument is

because the LCD will show three dash lines (-

the GSI 17 has a special "Sleep

shut down after

5 minutes of no

-).

Mode" in

"asleep"

To "wake

the instrument the operator only needs to press the Present There is no danger of presenting a loud tone to the test when the instrument

the

audiometer is

"wakes up""

awake.

automatically resets its output to 0

If the GSI 17 is operated until the battery charge below an

acceptable

function at all.

The display will be blank except for the LO BAT

voltage level,

because no tone is presented until

addition,

the

dBHL.

has

the

instrument

subject

instrument

dropped

will

up"

Bar.

not

indication, operation,

(full charge),

If the audiometer is operated via AC power (mains) with the rechargeable batteries in place,

occur.

10.4 ALKALINE BATTERY INSTALLATION/OPERATION

and the controls will not function.

the batteries must be recharged for

or AC power (mains) may be used.

some battery charging will

To restore

up to 18 hours

For

recharging batteries These

operation.

The batteries as it does for the NiCad batteries, that is, the LO BAT will be lit on the LCD when there are about 6 hours of continuous battery operation available. mode" also

useful life.

Before installing the alkaline batteries, unplug the GSI 17 from

the line power (mains).

remove the battery pack cover by removing the two screws that hold it in place, then lift off the cover. NiCad batteries out of the pack (they are wrapped in plastic and will come out of the pack as a single unit). disconnect the lead wires of the NiCad batteries from the battery compartment by disconnecting the small plug connector. notice six spring mounts on the top and bottom of the battery compartment. 10-3

longer,

batteries

low voltage indicator works the same way for

for a pictorial diagram of NiCad removal).

continuous battery operation, such as

on a regular basis is not possible, the

can

be replaced with six size C

will

works with the alkaline batteries to

These are for the alkaline batteries.

provide about

To install the alkaline batteries, first

45 hours of

alkaline

In addition, the

Carefully pull the

periods when

rechargeable

batteries. continuous

the

prolong their

alkaline

words

"sleep

Carefully

You will

(See Figure

Before inserting the alkaline batteries into the pack, check the label on the bottom surface of the compartment which indicates the correct polarity (orientation) of the batteries.

batteries in,

the label.

positioned with the spring mounts touching the batteries.

is only one way the cover fits correctly so that the screws are

secure.

If alkaline batteries are not going to be used

on a regular basis,

in the audiometer. from the battery pack and stored in a cool, dry place.

one at a time,

Replace the battery pack cover being sure it is

matching the polarity (+ or -) with

NOTE:

they should not be stored

They should be removed

Put the six

There

7044-0037

Figure 10-3:

NiCad

17 17-0406

BATTERY OPERATION

9’1

10.5 NiCad BATTERY ASSEMBLY PARTS LIST 1717-2010

Description

Base, Cover, Label, Assembly, Screw, Screw,Pan Hd.,

Battery

Battery Compartment

Battery Charge Board

Locking 6-32 x

6-32 x

.375

.750

lg.

Battery Pack, GSI 17, NiCad

Assembly,

(Not Replaceable -

Assembly,NiCad Conn.,

(Not Replaceable -

10.6 BATTERY BOARD FUNCTIONAL DESCRIPTION

Battery Contact Board, Top

Swaged)

Battery Contact Board

Swaged)

The Battery Charger Board serves several purposes.

Part No.

1717-7004 1717-7005 1717-0442 1717-4710 7044-0037 7044-1205 8410-0060 1717-0405

1717-2015

When

connected to the GSI 17 the charger board relay connects the

battery voltage to the GSI 17 power input. When a power module

is connected to the Battery ChargerBoard the applied voltage energizes

the relay which connects the charger board regulated

voltage to the GSI 17 power input. The charger board voltage

regulator U1 (LM2931) is capable of sourcing 150 ma which is used to power the GSI 17 and charge the NiCad Battery if installed. A resistive divider network on the board enables the GSI 17 A/D converter to determine if the GSI 17 is being powered by battery or via the power module.

Welch Allyn GSI 17 User manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Warranty

Table of Contents

FOREWORD

SECTION 1

Product Specifications

1.8 TRANSDUCERS HEADSET TDH39 Earphones with 60 ohm impedance

POWER AND POWER LINE

BATTERY PACK VOLTAGE

1.12 ENVIRONMENTAL CONDITIONS

MECHANICAL DIMENSIONS

Functional Description

2.4 POWER UP INITIALIZATION

SECTION 3

DISTORTION AND FREQUENCY SHIFT

4.2 CALIBRATION MODE OPERATION

CAL/NORMAL SWITCH

4.2.2 CALIBRATION MODE DIP SWITCHES

4.3 CALIBRATION MODE ENTRY The Calibration Mode can be entered via the Cal/Normal Switch at

TONE TYPE SWITCH

PRESENT BAR

HL DIAL

5.2 PARTS NUMBERS

6.6 TROUBLESHOOTING THE PROCESSOR

EPROM

8.5 POLLED CONTROLS

8.6 INPUT/OUTPUT (I/O) PORT DESIGNATIONS