AmpliVox CA850 series 5 User manual

CA850 Series 5 Audiometer Operating Manual 12 December,
2017
CA850 Series 5
Automatic Audiometer
Operating Manual

OM033-4 - CA850 Series 5 Operating Manual
ABOUT THIS MANUAL
READ THIS OPERATING MANUAL BEFORE ATTEMPTING TO USE THE INSTRUMENT.
This manual is valid for the CA850 Series 5 (applies from firmware version 0V56 onwards - see Setup screen).
This product is manufactured by:
Amplivox Ltd.
6 Oasis Park, Eynsham
Oxfordshire, OX29 4TP
United Kingdom
www.amplivox.ltd.uk
For all enquiries please contact us under:
Tel: [phone]
Fax: [phone]
[email protected]k

OM033-4 - CA850 Series 5 Operating Manual
TABLE OF CONTENTS
1INTRODUCTION ............................................................................................................................................ 1
1.1 INTENDED APPLICATIONS ....................................................................................................................................................1
1.2 UNPACKING INSTRUCTIONS .................................................................................................................................................1
1.3 WARRANTY CARD (UK CUSTOMERS ONLY) ............................................................................................................................1
1.4 STANDARD CONTENTS ........................................................................................................................................................1
1.5 OPTIONAL ACCESSORIES .....................................................................................................................................................1
2IMPORTANT SAFETY INSTRUCTIONS............................................................................................................. 3
2.1 PRECAUTIONS ...................................................................................................................................................................3
2.2 ELECTROMAGNETIC COMPATIBILITY (EMC) CONSIDERATIONS ..................................................................................................3
2.3 MAINS SUPPLY OPERATION .................................................................................................................................................3
2.4 AUDIOMETER CONNECTIONS ...............................................................................................................................................4
2.5 DATA TRANSFER TO A PRINTER OR USB DEVICE ......................................................................................................................4
2.6 DATA TRANSFER TO A COMPUTER.........................................................................................................................................5
2.7 DISPOSAL INFORMATION ....................................................................................................................................................5
3USING THE AUDIOMETER (OVERVIEW) ......................................................................................................... 6
3.1 FRONT PANEL LAYOUT ........................................................................................................................................................6
3.2 SWITCHING THE AUDIOMETER ON AND OFF ...........................................................................................................................6
3.3 TESTING THE PATIENT RESPONSE SWITCH ..............................................................................................................................7
3.4 USING THE TALKOVER FUNCTION .........................................................................................................................................7
3.5 TEST TYPES AVAILABLE........................................................................................................................................................7
3.6 USING AUDIOMETRIC DATA .................................................................................................................................................8
4AUDIOMETRY PREPARATION........................................................................................................................ 9
4.1 AMBIENT CONDITIONS........................................................................................................................................................9
4.2 TEST SYSTEM ARRANGEMENT ..............................................................................................................................................9
4.3 HEADSET..........................................................................................................................................................................9
4.4 PATIENT INSTRUCTIONS ......................................................................................................................................................9
5SEQUENCE OF OPERATION AND SUGGESTED TEST PROCEDURE ................................................................. 10
5.1 PATIENT DATA ENTRY ...................................................................................................................................................... 10
5.2 MANUAL TESTING........................................................................................................................................................... 10
5.3 BEKESY AND COMPUTER TESTING...................................................................................................................................... 10
5.4 MIXED MODE TESTING .................................................................................................................................................... 11
5.5 REVIEW RESULTS ............................................................................................................................................................ 11
5.6 OPERATIONAL DIAGRAM.................................................................................................................................................. 11
5.7 OPTIONS FOR DATABASE MANAGEMENT AND CONTROLLING THE TEST .................................................................................... 11
5.8 ENTERING PREVIOUS DATA AND PERFORMING A NEW TEST.................................................................................................... 11
6ERROR HANDLING & TROUBLESHOOTING .................................................................................................. 12
6.1 NO RESPONSE FROM PATIENT.......................................................................................................................................... 12
6.2 CONTINUAL RESPONSE FROM PATIENT .............................................................................................................................. 12
6.3 INCONSISTENT RESPONSE FROM PATIENT........................................................................................................................... 12
6.4 ERRORS IN TEST SEQUENCE.............................................................................................................................................. 12
7OPERATIONAL DIAGRAM............................................................................................................................ 13
8AUDIOMETER OPERATING MODES ............................................................................................................. 14
9TEST MODE................................................................................................................................................. 15

OM033-4 - CA850 Series 5 Operating Manual
9.1 OVERVIEW .................................................................................................................................................................... 15
9.2 PATIENT DETAILS PAGE .................................................................................................................................................... 15
9.3 AUDIOGRAM PAGE.......................................................................................................................................................... 16
9.4 TEST DETAILS PAGE ......................................................................................................................................................... 17
9.5 EXAMPLE –ENTERING PREVIOUS PATIENT &AUDIOGRAM DETAILS AND RE-TESTING.................................................................. 18
10 DATABASE MODE ....................................................................................................................................... 20
10.1 DATABASE OVERVIEW ................................................................................................................................................... 20
10.2 DATABASE SECURITY PAGE............................................................................................................................................. 20
10.3 DATABASE INITIAL PAGE ................................................................................................................................................ 21
10.4 SOFTKEY OPTIONS......................................................................................................................................................... 21
10.5 EXAMPLE –LOADING A RECORD FROM THE DATABASE AS A PREVIOUS TEST FOR RE-TESTING..................................................... 24
11 SETUP MODE .............................................................................................................................................. 25
11.1 OVERVIEW................................................................................................................................................................... 25
11.2 SETUP OPTIONS .......................................................................................................................................................... 25
11.3 SOFTKEY OPTIONS......................................................................................................................................................... 26
12 HEARING CATEGORISATION........................................................................................................................ 27
13 TECHNICAL SPECIFICATION ......................................................................................................................... 28
13.1 INPUT/OUTPUT............................................................................................................................................................ 28
13.2 AUDIOMETRIC.............................................................................................................................................................. 28
13.3 EARPHONE SOUND ATTENUATION CHARACTERISTICS ......................................................................................................... 28
13.4 OTHER FEATURES.......................................................................................................................................................... 28
13.5 PHYSICAL &ENVIRONMENTAL ........................................................................................................................................ 28
13.6 EQUIPMENT CLASSIFICATION .......................................................................................................................................... 28
14 PERFORMANCE STANDARDS....................................................................................................................... 30
15 SYMBOLS .................................................................................................................................................... 31
16 ROUTINE MAINTENANCE ............................................................................................................................ 32
16.1 AUDIOMETER MAINTENANCE.......................................................................................................................................... 32
16.2 TRANSDUCER MAINTENANCE .......................................................................................................................................... 32
16.3 MAINS ADAPTER MAINTENANCE...................................................................................................................................... 32
16.4 CALIBRATION AND REPAIR OF THE INSTRUMENT................................................................................................................. 32
16.5 GUARANTEE................................................................................................................................................................. 32
16.6 DISPOSAL OF INTERNAL BATTERY ..................................................................................................................................... 33
17 ORDERING CONSUMABLES, PARTS AND ACCESSORIES ............................................................................... 34
APPENDIX 1 –AMPLIVOX ‘ENCRYPTION’ FOR ENCRYPTION & DECRYPTION............................................................. 35
APPENDIX 2 –EMC GUIDANCE AND MANUFACTURER’S DECLARATION ................................................................... 41
APPENDIX 3 –USE WITH NON-MEDICAL EQUIPMENT .............................................................................................. 45

INTRODUCTION
1
OM033-4 - CA850 Series 5 Operating Manual
1INTRODUCTION
Thank you for purchasing the Amplivox CA850 Audiometer, an automatic screening instrument that
incorporates a number of innovative features making it an ideal instrument for use in today's health care
environment. It will give many years of reliable service if treated with care.
1.1 INTENDED APPLICATIONS
The CA850 Audiometer is designed for use by audiologists, general practitioners, hearing aid dispensers and
child health professionals.
Capable of undertaking automatic tests based on the Hughson and Westlake method (“Computer Test”) or
the Bekesy method (“Bekesy Test”), it can also be used for manual audiometry, but it is not intended for use
to determine the full extent and scope of a patient’s hearing deficiency.
Audiometric and patient data may be printed using a connected printer, stored in the internal database,
exported directly to a computer for use in applications such as the Amplivox Audibase database software, or
stored on a USB memory device (e.g. USB memory stick) with the option of encrypted data, for later transfer
to a computer.
Entering a patient’s previous test details (e.g. from paper records) and then conducting a new test followed by
printing and/or saving the results may be accomplished easily.
1.2 UNPACKING INSTRUCTIONS
Open the shipping carton and carefully remove all the equipment. Check against the delivery note that all the
accessories ordered have been included with your audiometer. If anything is missing, please contact Amplivox
Customer Support on [phone], email: [email protected]. If you have purchased from a
distributor you should contact them directly.
Please retain the shipping carton and packing materials as the audiometer will need calibrating on an annual
basis and should be returned in its original shipping carton.
1.3 WARRANTY CARD (UK CUSTOMERS ONLY)
Please complete the enclosed warranty registration card and return it to Amplivox Ltd to register your
purchase. This will help us to deal with your enquires, and we will also be able to send you details of updates
to your product and of new products and services.
1.4 STANDARD CONTENTS
CA850 audiometer
Audiometric headset
Patient response switch
Mains AC adapter (see Section 2.3)
USB memory stick
Carrying case
Audiogram paper (250 sheets)
Operating manual
Calibration certificate
1.5 OPTIONAL ACCESSORIES
Audibase audiogram software
Audiocups (noise reducing headset)
Designated Printer (including USB cable)
USB cable (to connect to PC)
Booth leads
ER75 Electro Acoustic Ear Simulator
Additional audiogram paper
(See Section 17 for details of part numbers etc)

IMPORTANT SAFETY INSTRUCTIONS
3
OM033-4 - CA850 Series 5 Operating Manual
2IMPORTANT SAFETY INSTRUCTIONS
The CA850 instrument must be used only by practitioners qualified to perform
audiometric tests. It is intended for use as a screening tool.
2.1 PRECAUTIONS
READ THIS OPERATING MANUAL BEFORE ATTEMPTING TO USE THE INSTRUMENT.
To comply with the standards IEC 60601-1 for safety and IEC 60601-1-2 for EMC the audiometer is designed
to be used only with the medically-approved mains adapter supplied, which is specified as part of the
equipment. Do not use any other type of mains adapter with this instrument. Refer to Section 17 for the
stock number of the adapter.
The audiometer is for indoor use only and should be used only as described in this manual.
The transducers supplied with the audiometer are specifically calibrated with it; if these transducers are
changed calibration will be required.
Do not immerse the unit in any fluids. See Section 16 of this manual for the proper cleaning procedure for the
instrument and its accessories.
Do not use the instrument in an oxygen-rich environment or in the presence of a flammable anaesthetic mixture
or other flammable agents.
Do not drop or otherwise impact this instrument. If the instrument is dropped or damaged, return it to the
manufacturer for repair and/or calibration. Do not use the instrument if any damage is suspected.
The instrument must be stored and used within the specified temperature, pressure and humidity ranges (see
Section 13).
Do not attempt to open, modify or service the instrument. Return the instrument to the manufacturer or
distributor for all repair and servicing requirements. Opening the instrument will void the warranty.
2.2 ELECTROMAGNETIC COMPATIBILITY (EMC) CONSIDERATIONS
Medical electrical equipment needs special precautions regarding EMC and needs to be installed and put into
service according to the EMC information in Appendix 2. This provides guidance on the electromagnetic
environment in which to operate the instrument.
Portable and mobile radio-frequency (RF) communications equipment can affect medical electrical equipment.
The instrument should not be used adjacent to or stacked with other equipment; if this is unavoidable the
instrument should be observed to verify normal operation.
2.3 MAINS SUPPLY OPERATION
The audiometer is designed for continuous operation and is powered by a mains adapter which is supplied,
and specified as part of the equipment. If a replacement is required, please contact Amplivox or your Amplivox
distributor.
All other connections must be made before connecting the output lead from the adapter into the POWER
input socket on the back of the audiometer. Switch on the mains supply - the indicator on the adapter and the
POWER indicator on the audiometer will both illuminate green, showing that the instrument is ready for use.
The output from mains adapter is fitted with electronic circuit protection. In case of overload the adapter will
shut down and the indicator will be extinguished. When the fault is cleared the adapter will operate as normal.
The input to the mains adapter is protected with a non-replaceable fuse. If this fails the adapter will not operate.

IMPORTANT SAFETY INSTRUCTIONS
4
OM033-4 - CA850 Series 5 Operating Manual
The mains adapter is the mains disconnect device and therefore the audiometer should be positioned such
that easy access to the mains adapter is possible.
2.4 AUDIOMETER CONNECTIONS
The rear panel layout is shown below.
All the relevant accessory terminals and connections are labelled to ensure correct identification and
connection as follows:
Socket
Label
Socket Type
Colour
Code
Connected Part
Notes
USB
PRINTER
USB Connector
Type A (Master)
Printer or USB Stick *
See 2.5
RIGHT
6.3mm jack
Red
Headset (right ear) *
LEFT
6.3mm jack
Blue
Headset (left ear) *
POWER
2.5mm power jack
Mains AC/DC Adapter *
RESP
6.3mm jack
Black
Patient Response Switch *
DATA
6 pin mini DIN
Reserved port; Amplivox
diagnostic use only
No user access
permitted
USB
PC
USB Connector
Type B (Slave)
Computer (via USB port)
See 2.6
The relevant part numbers are indicated in Section 17
For connected parts marked * only connect the accessories supplied with the
instrument or supplied by Amplivox or an Amplivox distributor. These parts have been
tested for use with the CA850 Audiometer for compliance with the standards IEC 60601-
1 and IEC 60601-1-2. The use of accessories other than those specified may
compromise compliance with these standards. For other sockets refer to Appendix 3.
2.5 DATA TRANSFER TO A PRINTER OR USB DEVICE
Please refer to Appendix 3 for important information regarding the
connection of non-medical electrical equipment to medical electrical
equipment
The audiometer can be used with a designated printer (see Section 17) to provide a hard copy of the
audiometric test data. The USB PRINTER socket is used for this function. See Sections 9.4.3 and 10.4.3 for
further details.

IMPORTANT SAFETY INSTRUCTIONS
5
OM033-4 - CA850 Series 5 Operating Manual
Additionally, a USB memory device may be connected to the USB PRINTER socket to enable transfer of the
entire patient database (e.g. for backup or importing into the Audibase application). See Section 10.4.7 for
further information.
2.6 DATA TRANSFER TO A COMPUTER
Please refer to Appendix 3 for important information regarding the
connection of non-medical electrical equipment to medical electrical
equipment
The audiometer can be used with a PC to transfer patient data directly to the Audibase application. The USB
PC socket is used for this function. You must use the designated USB cable which is available from Amplivox
(see Section 12). See Section 9.4.2 for further details.
2.7 DISPOSAL INFORMATION
Amplivox Limited is fully compliant with the WEEE (Waste Electrical and Electronic Equipment)
Regulations. Our PRN (Producer Registration Number) is WEE/GA0116XU and we are registered
with the approved WEEE Compliance Scheme, B2B Compliance, approval number
WEE/MP3338PT/SCH.
The main purpose of the WEEE Regulations is to encourage the segregation of waste electrical items from
the general waste stream and into reuse, recovery and recycling routes.
For any waste electrical units purchased from Amplivox that either:
bear the crossed out wheeled bin symbol with black bar underneath
or, have been replaced with new Amplivox products on a like-for-like basis
please contact our WEEE Compliance Scheme using the details below. B2B Compliance will be able to
provide further information on how to recycle your waste electrical units and answer any queries you may
have.
B2B Compliance
Tel: [phone] (Option 2)
Email: [email protected]

USING THE AUDIOMETER (OVERVIEW)
6
OM033-4 - CA850 Series 5 Operating Manual
3USING THE AUDIOMETER (OVERVIEW)
3.1 FRONT PANEL LAYOUT
The front panel layout is shown below.
A full-size keyboard is available for data entry. Use the SHIFT or CAPS keys to type capital letters, and the
ALT key to type the secondary symbols above the keys (£, $, # etc)
Four “softkeys” are provided to the right of the display, with functions as indicated adjacently on the display.
3.2 SWITCHING THE AUDIOMETER ON AND OFF
Press the key (see front panel layout). No warm-up time is required, but the instrument will load and run a
diagnostic check, which will take a few seconds to perform.
To switch off, press the key again and then the ‘Switch off’ softkey to confirm. To cancel switch-off press
the ‘Cancel’ softkey.
Note: This instrument is equipped with a real-time clock. Before use, ensure that the
date & time are set to local values in order that test data and calibration status are
correctly identified. Refer to Sections 11.2.13 & 11.2.14 for further details.
The clock is powered by an internal lithium cell battery which requires no maintenance
but should be disposed of according to local regulations at the end of life of the
instrument (see Section 2.7).

USING THE AUDIOMETER (OVERVIEW)
7
OM033-4 - CA850 Series 5 Operating Manual
3.3 TESTING THE PATIENT RESPONSE SWITCH
Press the patient response switch and the indicator labelled RESPONSE (to the right of the display) will
illuminate green.
3.4 USING THE TALKOVER FUNCTION
The CA850 is equipped with a Talkover function using the built in microphone to the left of the display. Press
and hold the TALK OVER button to interrupt the test and route the operator’s voice to the patient headset.
Adjust the volume level using the and keys while the button is pressed. The Talkover function is indicated
at the top of the display along with the volume level while the TALK OVER button is held down.
Release the button when Talkover has been completed, and use the indicated softkeys to repeat the frequency
that was being tested, move to the next frequency or cancel the test.
3.5 TEST TYPES AVAILABLE
Refer to Sections 4 & 5 for details of a typical test arrangement and a suggested test procedure with
operational sequence. Refer also to the appropriate audiometric standards.
3.5.1 Manual Test
Hearing thresholds may be recorded manually using the Plot point function. When used this will record a
threshold for the currently selected ear at the frequency and sound level indicated on the display (see Section
9.3.3).
3.5.2 Computer Test
This is a method of automatic audiometry based on the Hughson and Westlake method and undertaken
automatically by the instrument. The level is increased in 5dB steps until a response is obtained from the
patient and decreased in 10 dB steps until no response occurs. The process is repeated until, depending upon
the criteria selected for recording a threshold (see Section 11.2.9), the instrument will record a threshold at
that particular frequency. The next test frequency is then used in the same way, and so on to complete the
test.
3.5.3 Bekesy Test
This is method of automatic audiometry devised by Von Bekesy (1947) using pure tone stimuli to track auditory
thresholds.
This application is known as discrete frequency Bekesy testing and the principle behind the test is that the
patient adjusts the presented level according to his hearing threshold. The decibel level decreases when the
patient presses the response switch upon hearing the presented tone. Conversely when the patient can no
longer hear the presented tone, he will release the response switch therefore allowing the level to increase
until the presented tone is heard again. The level changes are in 2.5dB steps.
When a number of these "peaks" and "valleys" have been consistently performed, the audiometer will calculate
an average to the nearest dB and display this as the hearing threshold at that particular frequency. The next
test frequency is then used in the same way, and so on to complete the test.
3.5.4 Single Frequency Test
The CA850 provides the facility to repeat an automatic test at a specified single frequency and add the results
into the overall audiogram result. This feature is useful for situations where one particular frequency has
proved problematic.
3.5.5 Mixed Test
This is typically used when one of the automatic tests has been unable to yield a threshold at one or more
frequencies. It is possible to use the alternative automatic test or a manual test (normally at just a few selected
frequencies) to complete an audiogram by adding thresholds to those already established automatically. The
resulting audiogram will be labelled as a ‘Mixed’ test.

USING THE AUDIOMETER (OVERVIEW)
8
OM033-4 - CA850 Series 5 Operating Manual
3.6 USING AUDIOMETRIC DATA
3.6.1 Viewing test results
Once a test has been completed the results are available to view graphically, on the Audiogram page (Section
9.3) or numerically, on the Test details page (Section 9.4). Note that hearing thresholds may be entered directly
on the test details page if required. This is particularly useful for entering details of a previous test (e.g. from
paper records) before performing a new test (see Section 9.5 for an example).
3.6.2 Saving test results
Audiometric and patient data may be saved in the internal database (Section 9.4.1). This is referenced by a
patient number which should be uniquely assigned to each patient.
3.6.3 Exporting test results
Audiometric and patient data may be transferred to a computer running the Amplivox Audibase database
software, or similar application (Section 9.4.2).
3.6.4 Printing test results
If required it is possible to print audiograms using an optional designated printer. Pre-printed audiogram paper
is available for this purpose (Section 9.4.3).
3.6.5 Copying the database
The entire database may be copied on to a USB memory device with the option of data encryption for
enhanced security. This is vital for data backup purposes, but it is also possible to quickly transfer the data to
computer for use in Audibase (or similar application) by this means. Data may be transferred to the audiometer
in the same way (e.g. for restoring data) again with the option of data encryption. See Section 10.4.7.

AUDIOMETRY PREPARATION
9
OM033-4 - CA850 Series 5 Operating Manual
4AUDIOMETRY PREPARATION
Refer to the various audiometric standards and other relevant publications for guidance on audiometric testing.
4.1 AMBIENT CONDITIONS
Audiometric testing should always be performed in quiet conditions (e.g. a quiet room or an acoustic booth).
The optional Audiocups can provide an additional level of isolation from ambient noise. For further explanation
on permissible ambient noise levels, please refer to the audiometry standard ISO6189.
4.2 TEST SYSTEM ARRANGEMENT
The schematic diagram above shows a typical example of the use of audiometric test equipment. The
audiometer is located on the desk of a seated operator as shown.
The patient is seated in front of the desk facing away from the operator. The patient wears a headset (see
Section 4.3) and responds to test stimuli by use of a hand-held switch which is also connected to the
instrument.
4.3 HEADSET
The headset must be fitted by a qualified person to ensure a proper seal and a comfortable fit. The leads from
the headset are connected to the instrument and the headset is then fitted to the patient.
4.4 PATIENT INSTRUCTIONS
The patient should be given the following instructions using the TALKOVER function:
In the case of “Manual” or “Computer” testing, to press and release the response switch when a tone is
heard
In the case of “Bekesy” testing, to press the response switch when a series of pulses are heard and to
release when the pulses are no longer heard
Operator
Audiometer
Computer (optional)
Patient, wearing headset
Headset lead
Response switch & lead

SEQUENCE OF OPERATION AND SUGGESTED TEST PROCEDURE
10
OM033-4 - CA850 Series 5 Operating Manual
5SEQUENCE OF OPERATION AND SUGGESTED TEST
PROCEDURE
5.1 PATIENT DATA ENTRY
Press the TEST button and then the ‘New Person’softkey to clear any existing patient data. Enter the required
data as described in Section 9.2. The first line of data to be input is the patient number. As this is the reference
number for all other data (including audiometric test results) it is essential to use a unique patient number
for each patient.
Press the ‘Next page’softkey to advance to the Audiogram page.
5.2 MANUAL TESTING
The following notes are for guidance only –refer also to ISO 8253.
Use the ‘Erase’softkey and then the ‘This test’softkey to clear any existing test data.
Use LEFT/RIGHT keys to select the ear to be tested –an indicator above the selected key will illuminate
green. Use the and keys to change the frequency and the and keys to change the tone level. The
values are indicated on the bottom line of the display. Press the PRESENT key to present a tone to the patient
–an indicator above this key will illuminate green.
If the patient indicates that the tone has been heard, the level is decreased in 10dB steps until the patient
cannot hear the tone. Then increase the level by 5dB until the tone has been heard. Repeat the process until
there are 3 responses at the same level in 5 ascending series. Continue to the next frequency to be tested.
Press the ‘Plot point’ softkey to record the threshold, and then repeat the above steps at each required
frequency for both ears.
5.3 BEKESY AND COMPUTER TESTING
If necessary, switch between these test methods as described in Section 11.2.3.
Press the ‘Run Test’ softkey and then press a softkey to specify a test on both ears, the currently selected ear
or a single test using the currently selected ear & frequency combination.
For a both-ear or a single-ear test the option of running a familiarisation routine prior to the test is provided.
The message "Do you want to familiarise?" will appear at the top of the display. (Familiarisation is not available
for a single frequency test.)
a) Press ‘Yes’ to run the familiarisation routine prior to the test, or
b) Press ‘No’ to run the test without familiarisation, or
c) Press ‘Left ear’ to run the test with familiarisation only in the left ear (this option is only available for a
both-ear test).
After successful completion of the familiarisation routine the test will start automatically and will be performed
according to the test criteria and options selected (Section 11.2).
While the test is in progress the option to pause the test is available - press the ‘Pause’ softkey. The Talkover
function may then be used if required and the test may be resumed by using the indicated softkeys to repeat
the frequency that was being tested, move to the next frequency or cancel the test.
The time available for the patient to respond in Bekesy mode is from the point the
tone is presented until the point when the next tone in the sequence is presented.
In Computer mode the time to respond is from the point the tone is presented to the
beginning of the next presented tone (approximately 2.3 seconds maximum). If a
response is made within this time period a random delay is then added to the time
until the next tone is presented.

SEQUENCE OF OPERATION AND SUGGESTED TEST PROCEDURE
11
OM033-4 - CA850 Series 5 Operating Manual
At the end of the test a status message is shown at the top of the display. This will indicate a successful test,
or that an error had occurred, for example if a threshold could not be determined at a particular frequency.
Refer to Section 6 for information about errors that may occur during testing.
5.4 MIXED MODE TESTING
To add a test threshold to an audiogram (for example if an automatic test at a particular frequency has been
unsuccessful) the alternative type of automatic test at a single frequency or the manual test mode as described
in Sections 5.2 & 5.3 may be used. The audiometer display will change to “Mixed”.
In Bekesy & Computer test modes, if the manual test keys are operated the
audiometer will assume a “mixed” test mode has been entered and will adjust
the display accordingly.
To ensure exit from the “mixed” mode of testing, use “Erase > This test” prior
to starting a new Computer/Bekesy test (see Section 9.3.2).
5.5 REVIEW RESULTS
Press the ‘Next page’softkey to advance to the Test details page. The hearing thresholds and other associated
data may be reviewed and modified if necessary, and then saved in the internal database, printed or exported
to a computer (see Section 9.4).
5.6 OPERATIONAL DIAGRAM
The above operational steps are presented in a summary chart (see Section 7).
5.7 OPTIONS FOR DATABASE MANAGEMENT AND CONTROLLING THE TEST
For details for these functions refer to Sections 10 & 11.
5.8 ENTERING PREVIOUS DATA AND PERFORMING A NEW TEST
As this is a very common requirement, an example of performing this task quickly and easily using the CA850
Audiometer is provided in Section 9.5.

ERROR HANDLING & TROUBLESHOOTING
12
OM033-4 - CA850 Series 5 Operating Manual
6ERROR HANDLING & TROUBLESHOOTING
6.1 NO RESPONSE FROM PATIENT
If the patient does not operate the response switch and the maximum output level is reached, the test at that
particular frequency will be repeated according to the ‘Retries’ setting (see Section 11.2.4).
If a response is still not made then the message “No response!” is displayed at the top of the screen. The test
will then be paused with options to retry the same frequency, skip to the next frequency or cancel the test. If
the test is cancelled then any thresholds that have been established will be retained.
6.2 CONTINUAL RESPONSE FROM PATIENT
If the patient holds the response switch on continuously and the minimum output level is reached, the test at
that particular frequency will be repeated according to the ‘Retries’ setting (see Section 11.2.4).
If the response switch is still held then the message “Response not released!” is displayed at the top of the
screen. The test will then be paused with options to retry the same frequency, skip to the next frequency or
cancel the test. If the test is cancelled then any thresholds that have been established will be retained.
6.3 INCONSISTENT RESPONSE FROM PATIENT
If the patient does not respond in a consistent manner and a hearing threshold cannot be established, the test
at that particular frequency will be repeated according to the ‘Retries’ setting (see Section 11.2.4).
If the response is still inconsistent then the message “Test failed!” (Bekesy test) or “Frequency failed!”
(Computer test) is displayed at the top of the screen. The test will then be paused with options to retry the
same frequency, skip to the next frequency or cancel the test.
If the test is cancelled then any thresholds that have been established will be retained.
If the next frequency is chosen the test will continue, but at the end of the test the message “Test completed
with errors” is displayed at the top of the screen.
6.4 ERRORS IN TEST SEQUENCE
If one or more thresholds cannot be recorded for other reasons the message “Test completed with errors” is
displayed at the top of the screen.
The operator may then re-test the patient at specific frequencies that were problematic using the Mixed test
mode if appropriate (Section 5.4).

OPERATIONAL DIAGRAM
13
OM033-4 - CA850 Series 5 Operating Manual
7OPERATIONAL DIAGRAM

AUDIOMETER OPERATING MODES
14
OM033-4 - CA850 Series 5 Operating Manual
8AUDIOMETER OPERATING MODES
The CA850 Audiometer has three operating modes, TEST, DATABASE and SETUP. Select one of these
modes by pressing the appropriate key at the left hand side of the display. The indicator above the key will
illuminate green. In order to perform an audiometric test, the CA850 Audiometer must be in the TEST mode.
When first powered-up the audiometer enters TEST mode and displays the Audiogram page (see Section
9.3). This is to allow the operator to perform the checks necessary to confirm that the audiometer is operating
correctly prior to carrying out tests on a patient.
When TEST mode is selected at any subsequent time the Patient details page (see Section 9.2) is displayed
in anticipation of the requirement to enter patient-specific data prior to performing a test on that patient.
The following sections describe these operating modes and the function of controls.

TEST MODE
15
OM033-4 - CA850 Series 5 Operating Manual
9TEST MODE
9.1 OVERVIEW
There are three pages available in the TEST mode which may be selected in turn by pressing the ‘Next Page’
softkey.
Note: As entering previous patient data and then immediately running a new test is a very common
requirement, examples of performing this task quickly and easily using the CA850 Audiometer are provided in
Sections 9.5 & 10.5.
9.2 PATIENT DETAILS PAGE
To enter information about a patient the patient details page is used (see below).
Patient details are added or modified by using the and keys to select the required line and then using the
keyboard to enter the details. The back-arrow key will delete characters. A mixture of letters and numbers is
allowed in the data but please note that it is essential to use a unique patient number for each patient.
SOFTKEY OPTIONS
9.2.1 New person
To enter the details of a new patient the ‘New person’ softkey must be selected to ensure all details of
the previous patient are erased.
9.2.2 Next Page
Press the ‘Next Page’ softkey to access the following page within the TEST mode.

TEST MODE
16
OM033-4 - CA850 Series 5 Operating Manual
9.3 AUDIOGRAM PAGE
To perform an audiometric test the audiogram page is used (see below).
SOFTKEY OPTIONS
9.3.1 Run Test
Press the ‘Run test’ softkey to initiate a test sequence. Two further options require selection –the selection of
the ear(s) to test and familiarisation (if required)
9.3.1.1 Both ears
Press the ‘Both ears’ softkey to ensure that both the left and right ears will be tested.
9.3.1.2 This ear
Press the ‘This ear’ softkey to perform the test on the specified ear (the indicator above the LEFT or RIGHT
key will illuminate).
9.3.1.3 Single frequency
Press the ‘Single freq’ softkey to perform the test at the specified frequency (as indicated on the display) on
the specified ear (the indicator above the LEFT or RIGHT key will illuminate).
9.3.1.4 Cancel
Pressing the ‘Cancel’ softkey will cancel the ‘Run Test’ function.
9.3.1.5 Familiarise?
When the test selection has been made the option to run a familiarisation routine is presented. This allows the
patient to make responses to the test stimuli prior to the actual test with the operator monitoring these
responses to ensure consistency. For a test on both ears the option to use just the left ear for familiarisation
is available.
9.3.2 Erase
Press the ‘Erase’ softkey to delete the specified data as defined below. (Note that this function applies to
current hearing thresholds only and does not affect the patient details entered or any data held within the
internal database.)
9.3.2.1 This point
Press the ‘This point’ softkey to erase the hearing threshold at the indicated frequency.
9.3.2.2 This ear
Press the ‘This ear’ softkey to delete all hearing thresholds for the selected ear.
9.3.2.3 This test

TEST MODE
17
OM033-4 - CA850 Series 5 Operating Manual
Press the ‘This test’ softkey to delete hearing thresholds.
9.3.2.4 Cancel
Press the ‘Cancel’ softkey to cancel the erase selection and return to the audiogram page.
9.3.3 Plot point
Pressing the ‘Plot point’ softkey will plot a hearing threshold for the specified ear, frequency and sound level.
This feature is used when performing manual audiometry in conjunction with the and keys (to change
frequency) and the and keys (to change level).
9.3.4 Next Page
Press the ‘Next Page’ softkey to access the following page within the TEST mode.
9.4 TEST DETAILS PAGE
The Test Details page is normally used to view test details numerically. However it is possible to enter data
directly on this page, for example the examiner, threshold values and the test date. Use the and keys to
select the required data field and enter data from the keyboard. Thresholds are always entered in the
‘Current’ columns (use ‘ALT’ ‘I’ to enter a negative value). If specific frequencies have been omitted from the
test (see Section 11.2.6) thekey may be used to skip over these data fields.
Refer to Section 9.5 for details of how to enter patient details and previous data, and then immediately
perform a new test.
SOFTKEY OPTIONS
9.4.1 Save test
Press the ‘Save test’ softkey to save the test record within the internal database. If a record with the same
patient number and date already exists, the operator will be prompted either to create a new record or overwrite
the existing one. If required, the database functions may be used to confirm the save operation (see Section
10).
9.4.2 Data export
Press the ‘Data export’ softkey to transfer the displayed test record to Audibase (or other computer-based
application). Note that the CA850 needs to be connected to a computer with Audibase correctly configured to
allow this (refer to the Audibase documentation). Data is transferred via the ‘USB PC’ socket.
9.4.3 Print
Press the ‘Print’ softkey to print the audiogram on a printer connected to ‘USB PRINTER’ socket. Pre-printed
audiogram paper is available for this purpose. Note: Printer initiation can take several seconds - do not
press the ‘Print’softkey again until the printout has been generated.