If you are located in the European Union, please report all safety-related concerns to our autho
rized representative:
Siemens Hearing Instruments
Alexandra House
Newton Road
Manor Royal
Crawley
West Sussex RH109TT
England
Otherwise, please report all safety-related concerns to:
Frye electronics, Inc.
P.O. Box 23391
Tigard, OR 97281-3391
USA
Frye Electronics is a Registered Firm of British Standards Institution, and
we conform tothe ISO 13485 standard
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viii
Chapter 1: Introduction
1.1 Description
Hearing aid analyzers are designed to give the user accurate information on how much amplification the aid provides, which frequencies it amplifies, how loud it can get, and how much distortion
and noise are present. Information is displayed in both graphs and in number tables, and can be
printed as desired.
The FP40 Hearing Aid Analyzer is the third generation of portable analyzers manufactured by Frye
Electronics. It incorporates a tilt-up, wide-angle LCD (liquid crystal display), a quiet, fast thermal
printer, and a convenient, optional battery pack for testing in places where it is not convenient to
use electrical outlets. The lid holding accessories comes off so that the unit looks like a desk model
in your office.
The following test sequences are currently available on the FP40: ANSI (American National
Standards Institute); IEC (International Electrotechnical Commission); JIS (Japanese Industrial
Standard) and ISI (Indian Standards Institute). Your choice of one of these is included in the stan
dard price. Additional test sequences can be included at a modest cost. Instructions for the ANSI
and IEC test sequences are found in Chapter 5. Instructions for the JIS automated test sequence are
available upon request.
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The FP40 comes standard with three types of pure-tone sweeps: normal, fast, and short. The
Composite Options adds three real-time signals: the Composite signal, Digital Speech ANSI, and
Digital Speech ICRA. These signals are described in more detail in Section 1.3.
Indications for use
The FONIX FP40 Hearing Aid Analyzer allows the user to test the characteristics of a hearing
aid using coupler and optional real-ear measurements. These characteristics include: Frequency
response, harmonic distortion, equivalent input noise, battery current drain, and compression.
Coupler measurements are performed inside a sound chamber. Real-ear measurements are per
formed with a small probe microphone inside the patient’s ear. This manual provides detailed
instructions on the measurement capabilities and user interface of the FONIX FP40.
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1.2 Hardware History
Here’s some of the recent hardware changes to the FP40:
In 1994, we introduced the VG
video monitor for a large, colorful display. (In 1999, this VGA Option became a standard feature.)
At the same time, we introduced the Telecoil Option to allow telecoil testing. It requires separate
hardware such as the ANSI 87 telecoil board or the ANSI 96 telewand.
A Option that allowed the FP40 to be hooked up to an external color
Introduction 1
Also in 1994, we introduced the FP40-D desk model analyzer. This unit is always equipped with the
real ear testing function. In order to minimize costs, the Battery Pack Option is not available on this
unit and some accessories (battery pills and monitor headset) that are standard on the FP40 are
optional with the FP40-D. Since this unit does not have a lid, a separate soft carrying case is avail
able for those who want to carry the unit from place to place.
In 1996, we improved the sound chamber significantly. The new sound box excludes much more
ambient noise than the previous model did. It was designed to be taken out of the module and
placed on a short pole for use as a speaker for real ear measurements. The speaker is then at a
higher elevation than in the previous design and can be swiveled, allowing easy positioning for real
ear measurements.
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1.3 Features & Options
This section describes many of the different features and options available on the FP40 hearing aid
analyzer
1.3.1 Composite/Digital Speech Option
In addition to pure-tone tests, the FP40 can be purchased with the Composite Option, providing
real-time measurements of hearing aids. The Composite and Digital Speech signals are complex sig
nals made up on 79 different frequencies presented simultaneously, updating about once a second.
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Besides giving instant results, these test signals often provide more realistic test results of hearing
aids than you can get using pure-tone sweeps. Aids with automatic gain control (AGC) technology
can respond unexpectedly to pure-tone sweeps, providing more amplification in the low frequen
cies than would occur in a real-life situation. This artifact of pure-tone testing, known as “artificial
blooming,” does not occur when a complex signal, such as the composite signal, is used.
Advanced digital hearing aids with “noise suppression” have different difficulties with testing. These
aids were designed to lower their gain when in the presence of a continuous sound. Unfortunately,
this generally includes conventional test signals such as pure-tone sweeps or the standard composite
signal. Digital Speech was developed as a way to test these advanced hearing aids. Digital Speech is
very similar to the composite signal except that instead of being a continuous signal, it is an inter
rupted signal that the aid responds to as it would respond to speech.
Digital Speech comes with two speech weightings: ANSI and ICRA. The ANSI speech weighting is
from the ANSI S3.22-1992 standard – it is the same weighting used by the standard Composite sig
nal. The ICRA speech weighing is from a CD of sounds from multiple languages developed by the
International Collegium of Rehabilitative Audiology. It rolls off the high frequencies more rapidly
than the ANSI weighting.
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2 FONIX FP40 Portable Hearing Aid Analyzer
The use of the Composite or Digital Speech signals can uncover the presence of intermodulation
distortion in a hearing aid. Intermodulation distortion is the distortion that results when two or
more frequencies are delivered to the hearing aid simultaneously, resulting in the addition of fre
quencies to the output that were not present in the input. In other words, when you deliver a com
plex signal to the hearing aid, such as speech, the aid provides unexpected amplification to some of
the frequencies, causing the entire signal to sound distorted.
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Intermodulation distortion can be detected using the composite or digital speech signals and look
ing for jagged peaks and valleys in the response curve. The curve “breaks up” more and more as the
amount of intermodulation distortion increases.
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1.3.2 Probe Option (standard on the FP40-D)
(See Chapter 5 for details.)
The FP40 Hearing Aid Analyzer can be ordered with the Probe Option so that tests can be done on
the hearing aid while it is in the client’s ear. Probe measurements are also known as “real-ear” mea
surements. It is then possible to individualize the fitting of a hearing aid since a coupler measure
ment can seldom tell the operator exactly what sound is received by the client. Many factors affect
the sound on its way to the ear drum. When measuring with a probe microphone, you will know
what is happening in the “real ear.”
The probe microphone can also be used as a reference microphone while making coupler measure
ments.
Target 2-cc
The Target 2-cc screen on the FP40 converts real-ear targets to coupler targets. It can be used for
ordering hearing aids from a manufacturer, and it can be used for adjusting the hearing aid to tar
get when a real-ear measurement isn’t possible. Further refinements of the coupler target are pos
sible using a measured real-ear to coupler difference (RECD) measurement. This is explained in
more detail in Chapter 5.
Prescription
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1.3.3 External Video Monitor
In September 1994, the VGA Color Option was introduced on the FP40. This allowed the FP40 to
be hooked up to an external video monitor. In 1999, we made this a standard feature. When the
VGA display mode is chosen, the LCD is blanked.
When purchasing a VGA monitor for your FP40, it is recommended that you get one with a 0.31 or
0.28mm dot pitch so that you get the resolution needed to take full advantage of the FP40 video
resolution.
1.3.4 Battery Pack Option
Some users may find it convenient to operate their unit away from electrical outlets. These users
can order the Battery Pack Option which will operate on its rechargeable batteries for up to three
hours. (Not available on the FP40-D.)
Introduction 3
1.3.5 ID Option
The ID Option personalizes the printout strips with the owner’s name and address or phone
number. Specify two lines of 27 characters each at time of purchase, and we will program them
into your instrument. The ID can be changed for a modest fee with an exchange of PROMs
(Programmable Read Only Memory).
1.3.6 RS232 Option
The RS232 Option allows you to hook your analyzer up to a computer so you can grab your analyzer data from your analyzer and save it on your computer. It includes internal FP40 software and
external RS232 cables and connectors. In order for you to communicate with your analyzer, you
will also need a corresponding program on your computer, such as WinCHAP. It is also possible to
create your own custom program for communicating with your FP40.
1.3.7 OES (Occluded Ear Simulator) Option
The OES Option provides special couplers, (the MZ series) and correction factors to produce the
same results as a real ear simulator (Zwislocki coupler) when simulating occluded ear measure
ments in the sound chamber. See Section 3.7 for more details.
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1.3.8 CIC (Completely In the Canal) Option
The CIC Option was designed as a realistic coupler test for CIC hearing aids. It uses a 0.4 cc coupler combined with software correction factors in order to create a response curve that is more like
what you would expect to see in a person’s ear than the response curve you will get using a stan
dard HA-1 coupler. See Section 3.6 for more details.
4 FONIX FP40 Portable Hearing Aid Analyzer
1.4 Accessories
The standard and optional accessories available for the FP40 analyzer are described in this
section.
1.4.1 Standard Accessories
Microphone Adapter
14 mm to ANSI 1" diameter microphone
size. This is used for calibrating the FP40
microphones.
HA-2 2-cc Coupler
Dimensions per requirements of ANSI
S3.7 for testing ear level, eyeglass and
body aids.
HA-1 2-cc Coupler
Dimensions per requirements of ANSI
S3.7 for testing in-the-ear aids.
Ear-Level (BTE) Adapter
Snaps into the 1/4" (6.35 mm) diam
eter cavity in the HA-2 2-cc coupler or
the MZ-2 coupler. Equipped with a 0.6"
(15 mm) length of 0.076" (1.93 mm)
ID tubing, the adapter allows ANSI
S3.22 specified connection of an earlevel aid to the coupler.
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Introduction 5
FM40 Microphone
Provided if the Real-Ear Option is not
ordered.
1.4.2 Optional Accessories
Battery Pills
(With 12" [30 cm] cables — 24" [60
cm]) cables available upon request)
#13, #675/65, #312, #10A/230. (All
pills optional with FP40-D).
Operator’s Manual
6-CC Coupler
Per ANSI S3.7 for NBS 9A—used to
check output of audiometers.
6 FONIX FP40 Portable Hearing Aid Analyzer
Sound Level
For microphone calibration
Calibrator
6040 Sound Chamber
For control of external noises.
External Telecoil
For checking the response of aids in
the “telephone” mode.
Open Ear Coupler
Non-standard coupler used for
realistic testing of open ear hear
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ing aids.
RECD Earphone Package
Consists of one ER3A earphone with a
phono plug, a 72 inch cable, an assort
ment of ear tips, a calibration certifi
cate, and a lapel clip. This package is
suitable for performing an RECD mea
surement with the FP40 analyzer.
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CIC Coupler
Required coupler for use with
Option.
#5 Battery Pill
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-
12" or 24"
Needed for some CIC hearing aids.
CIC
Introduction 7
Child Size Wedge Style Earhook
Holds probe and reference microphones
during real ear testing.
•Y adapter for using both external printer and RS232
• Eartips for insert earphones:
Eartips, 3A medium, 50/pk
Eartips, 3B small, 50/pk
Eartips, 3C large, 25/pk
• Battery Pills, #AA, #41 (with 12" cables. 24" cables available upon request)
•Maintenance Manual (on request at time of purchase
Telewand
For checking the telecoil response per
ANSI-S3.22-1996
1.4.3 Real-Ear Accessories
M200 Probe Microphone
8 FONIX FP40 Portable Hearing Aid Analyzer
Mounting Sleeves
(L) for reference mic
(R) for probe mic
Wedge Style Ear Hook
Standard size
Holds probe and reference microphones
during real ear testing. Improved design
eliminates need for Velcro headband.
Optional Swing Arm, Speaker,
and Cable
Allows precise placement and aiming
of the loudspeaker.
Monitor Headset, folding
(Optional with FP40-D)
Other Real Ear Accessories
Set of 25 Probe Tubes
Ear hook, standard size
Ear Hook, children’s size
Velcro Headband
Calibration Clip
Felt Pen-dry erase
Probe Calibration Adapter
Introduction 9
Infant/Child Headband Package
Includes infant, child, and adult head
bands, six flexible earhooks, and two
sets of “animal ears.”
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1.5 Layout & Controls
F1F2F3F4F5F6F7F8F9
LINE POWER
OPERATE
RESET
LEVEL
START/
STOP
DATA/
GRAPH
PRINT
FEED
FREQUENCY
AMPLITUDE
CONTRAST
F1F2F3F4F5F6F7F8F9
POWER
RESET
LEVEL
START/
STOP
DATA/
GRAPH
PRINT
FEED
FREQUENCY
AMPLITUDE
CONTRAST
This section gives a short explanation of the layout of the FP40 analyzer, its controls, and its functions
1.5.1 LCD (Liquid Crystal Display)
The FP40 is equipped with an LCD screen that displays test results and operational instructions in
both alphanumeric and graphical formats. This display is mounted on a swing-up door that can be
adjusted for optimum viewing by the operator.
Hint: If no display appears on the LCD screen, turn the contrast knob in the upper right corner, or
press any key.
Figure 1.5.1A—FP40 Front Panel Function Buttons
Figure 1.5.1B—FP40-D Front Panel Function Buttons
10 FONIX FP40 Portable Hearing Aid Analyzer
1.5.2 Front Panel Buttons
There are nine function key buttons in the top row of the FP40 front panel. The function of each of
these keys changes as you move from screen to screen on the FP40.
The rest of the front panel buttons have specific functions that do not change with each new menu
selection.
Feed Feeds the paper through the printer.
Print Produces a hard copy of the data and graphs displayed on the LCD screen or
monitor screen.
Data/GraphAllows the screen presentation to be switched from graph to data table and
back again.
Start/StopStarts or continues or stops a measurement action, depending on the particular
measurement task. When the instrument is running a continuous measure
ment, this button starts or freezes the measurement on the display. START/
STOP is also used to activate a menu selection.
FP40s manufactured prior to 8/22/90 are marked START/CONTINUE.
LevelAlong with START/STOP button, initiates a leveling action that takes a
response measurement and develops a set of frequency response corrections to
adjust the signal so that it is at the correct level for each test frequency.
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ResetResets the test signal to the amplitude and frequency you have chosen in the
SETUP MENU and interrupts current operation.
OperateStarts and terminates the measurement operation of the FP40. Use operate to
turn the instrument on and off. (There is no operate button on the FP40-D.)
1.5.3 Front Panel Lamps
Line Power Signals that the FP40 is connected to the power line, and that the main rear
panel-mounted power switch is switched “on.” If the Battery Option is installed,
this lamp may also indicate that the battery is being charged.
OperateWhen lighted, signals that the instrument is active. (Not on the FP40-D).
Introduction 11
1.5.4 Front Panel Knobs
EXTERNAL
POWER
ON
OFF
HEADPHONES
EXTERNAL
SPEAKER
VIDEO MONIT
OR
SERIAL
INTERFACE
CAUTION
ELECTRICAL SHOCK HAZARD.
DO NOT REMOVE INSTRUMENT COVER.
REFER SERVICE TO QUALIFIED PERSONNEL.
0 08 6
AmplitudeControls the amplitude or loudness of the test signal. Is also used to move the
cursor up and down in making menu selections.
FrequencyControls the frequency of the test signal in pure-tone mode. Is also used to
move the cursor left and right when making menu selections. In the real-ear
target screen, it selects the amplitude in the audiogram tables.
Contrast Control Controls the contrast of LCD display. If no display appears, check this control
first.
Figure 1.5.5—Rear Panel
1.5.5 Rear Panel Controls
External Speaker A miniature phone jack that allows an external sound field speaker or sound
box (FONIX 6040) to be connected to the speaker drive from the FP40.
Headphones A standard 1/4 inch phone jack and volume control that allows the monitoring
of the sound reaching the probe microphone.
Serial Interface Nine pin D jack for RS232 connection and laser printer connection.
CE Mark This symbol indicates that Frye Eelctronics conforms to the Medical Device
Directive 93/42/EEC. If an external monitor or printer is used, it should also
have a CE mark in order for the FP40 to remain compliant.
Video MonitorUnits with serial numbers 940000 and above have VGA connectors. Older units
have RCA jacks for composite
External Power Main power input switch. (On the portable version, operate button on front
panel must also be pushed to activate the instrument.)
12 FONIX FP40 Portable Hearing Aid Analyzer
monitors.
1.5.6 Right Side Mounted Jack and Module
Paper Release Lever
Printer Door
Line input connector, IEC computer variety.
Dual “snap in” fuse holder.
Instrument will automatically choose the proper voltage.
Found on the left side of the sound chamber, near te speaker.
Marked: Probe Gain and Ref. Gain.
1.5.8 Top of Instrument, Printer
Figure 1.5.8—Electronics Module Top View
Introduction 13
1.6 FP40 Setup
FONIX FP40
EXTERNAL
PRINTER
SERIAL-TO-PARALLEL
CONVERTER
SERIAL INTERFACE
This section describes how to set up the FP40 analyzer and prepare it for testing.
1.6.1 Setting up the instrument
Unpack and locate all accessories (in the lid/FP40; in the boxes/FP40-D). Save the shipping box in
case you need to send the unit in to us for repair or major upgrades. Choose a location for the FP40
which is relatively free of ambient sounds and vibrations. See Figure 1.5.5 for a drawing of the rear
panel
1.6.2 Connecting equipment
If you want to connect an external printer, you must have the External Printer Kit. This kit consists
of a special serial-to-parallel converter, a printer cable, a couple connectors, and an RJ11 cable. See
Figure 1.6.2.
14 FONIX FP40 Portable Hearing Aid Analyzer
Figure 1.6.2—External printer setup
1. Make sure the FP40 is turned off.
2. Attach the connector labeled “FP40 Printer” to the serial interface connector on the back of
the FP40.
3. Attach the RJ11 cable to the FP40 printer connector
4. Attach the connector labeled “Printer” to the other end of the RJ11 cable.
5. Attach the printer connector to the “RS232” side of the serial-to-parallel converter.
6. Attach the printer cable to the “Parallel” side of the serial-to-parallel converter.
7. Attach the other end of the printer cable to your external printer.
If desired, plug in an external video monitor to the connector labeled “Video Monitor” on the back
of the FP40.
You can also plug in an external sound chamber or an external sound field speaker into the “exter
nal speaker” jack of the FP40.
Hint: When something is plugged into the external speaker jack, the sound source of the FP40 is
always delivered to that external source, regardless of whether you are performing a coupler test or
a real-ear test.
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1.6.3 Connecting the line cord
Plug the line cord into the jack on the right side of the analyzer. Push the on-off rocker switch on
the back of the unit. The green LED labeled “line power” (FP40) or “power” (FP40-D) will light up.
This will turn on the analyzer if you have an FP40-D model. To fully turn on an FP40 model ana
lyzer, push the square gray button marked OPERATE on the front panel.
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1.7 Miscellaneous
This section describes how to clean and service your FP40 analyzer. Warranty information is also
included.
1.7.1 Servicing Your FP40
Contact Frye Electronics, Inc., Box 23391, Tigard, Oregon 97281-3391 for service. Our toll-free
number is 1-800-547-8209. Our regular number is (503) 620-2722, or you may contact your local
Frye representative. We are also available on the internet. Our e-mail address is: service@frye.com,
and our web site is http://www.frye.com.
Units may be returned to Frye Electronics, Inc., 9826 S.W. Tigard St., Tigard, Oregon 97223. It is
advisable to contact the company or your local Frye representative first, since many problems can
be fixed without returning the whole unit. Printed circuit boards, for instance, may be exchanged. If
something must be returned, an RMA number will be issued.
When contacting the factory, please have the serial number of your instrument on hand. (Found on
the rear panel of the instrument.) It will also be helpful for you to be able to tell us the software
version installed on your machine. The software version and date of release are found on the LCD
when you turn the unit on (FP40-D) or press OPERATE (FP40).
1.7.2 Cleaning the FP40 Display
Cleaning of the FP40 LCD screen should be kept to a minimum to avoid scratching the surface. To
clean the LCD, first blow off any loose dust. Then wipe gently with a soft cloth moistened with glass
cleaner. The surface of the LCD is waxed to minimize scratching.
Introduction 15
1.7.3 Emergency Shutdown
If you find it impossible to turn off the instrument using the OPERATE button in units with a
Battery Option, hold OPERATE down and then tap RESET twice. Or you can simply hold the
OPERATE button down for five seconds.
1.7.4 Warranty
The FONIX FP40/FP40-D and its accessories are guaranteed to be free from manufacturing defects
which would prevent the products from meeting these specifications for a period of one year from
date of purchase.
Battery pills are warranted for thirty days because they are necessarily fragile and can be damaged
by careless handling.
16 FONIX FP40 Portable Hearing Aid Analyzer
Chapter 2: General Operation
This chapter discusses the general operation of the FP40 analyzer. You will learn how to navigate
through the different screens, use the General Setup Menu, and change the function keys to suit
your purposes. Other general operational topics will also be discussed such as source types, battery
pills, printers, and other topics.
2.1 Screen Navigation
You move through the different screens of the FP40 by using the function keys. The function keys
are the top row of buttons of the FP40 front panel labeled F1 through F9. Each button is labeled on
the display screen just above the function keys.
For example, in most screens, F1 is labeled “MENU.” This means that you get to the Menu by press
ing F1.
Hint: Whenever a function key is labeled with large letters, it is a navigational key. That is, pressing
it will take you to a different screen.
2.2 General Setup Menu
In the General Setup Menu, you can change most of the settings on the FP40. To enter the General
Setup Menu, press F1 from almost any screen.
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Figure 2.2—General Setup Menu
General Operation 17
2.2.1 Making selections
Notice the three columns in the General Setup Menu. Move the selection indicator (lines above
and below the selection) from one column to another using the FREQUENCY knob. Move the knob
slowly. You will feel each position change. Move the selection indicator up and down within the col
umns with the AMPLITUDE knob.
Push the START/STOP button, found in the very center of the front panel, to switch between the
available choices at the indicated position.
2.2.2 Saving changes
Unless you purposely make setup changes permanent, they will only be effective until you turn off
the analyzer. When the analyzer is turned on again, it will revert to default settings. However, you
can change the default settings to suit your own needs.
• To change the default setting of an individual item, highlight the item in the General Setup
Menu, change it to the desired setting, and press F8. This will store the individual item set
ting.
• To set the default settings of the entire menu at once, make any desired changes in the
General Setup Menu, and press F9. This will store the entire menu.
-
2.2.3 Switching between partial and full menus
-
Not all the items in the General Setup Menu will apply to every screen of the FP40. In order to
avoid information overload, the FP40 has a “Partial
If the FP40 is in PARTIAL Menu mode, it will only display the items of interest to the screen you
just left. For instance, if you enter the General Setup Menu from the Main Coupler Screen, the par
tial menu will not display Probe Settings. Also, if you have selected a composite signal source, it
will not display the pure-tone settings.
When the FP40 is in FULL Menu mode, it will display all available settings, regardless of the screen
that you just left or the signal source you have chosen.
To switch between Partial Menu mode and Full Menu mode, select MENU TYPE in the General
Setup Menu. Choose between FULL and PARTIAL.
Menu” mode.
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18 FONIX FP40 Portable Hearing Aid Analyzer
2.3 Using Function Keys
The front panel of the FP40 analyzer contains nine function keys, F1 through F9. These keys control
the navigation through the FP40 screens as well as some settings in each screen.
2.3.1 Hints
The first thing you need to understand when working with the FP40 is the concept of “function
keys.” In order to make it easier to add new functions and screens to the FP40, we made the func
tion of keys F1 through F9 vary, depending upon the current screen and your current settings. Here
are three simple things to remember about function keys:
• The function of the keys vary, depending upon the current screen
• The labels above the keys always indicate the function of that key. They are never labels for
the current screen.
• Small labels indicate the function key toggles a setting. Large labels indicate the function key
will take you to a different screen.
These three points are explained in more detail below.
Varying Function Keys
The function of the keys vary, depending upon the current screen. There are nine function keys
used on the FP40 to toggle common settings and switch between screens. We’ve tried to make the
function of each key be as consistent as possible when you switch from screen to screen.
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For example,
• F1 is generally the “MENU” key. Pressing it will usually take you to the General Setup Menu.
• F4 in the Main Coupler Screen will take you to an automated test sequence such as ANSI. F4
in the ANSI Screen will exit you back to the Main Coupler Screen.
The function of each key for each screen is clearly labeled above the function key on the display.
Function Key Labels are NOT Screen Labels
As mentioned above, the function of each key is labeled on the display above the key. This label
always denotes the function of the key. Function key labels are never labels for the current screen.
Sometimes it’s easy to see “PROBE” above F5 and think that you are in the probe screen. Remember
that the label above F5 actually means that you need to press F5 in order to enter the Probe Screen.
The actual labels for the screens can usually be found in the top center of the screen.
Small Labels vs. Big Labels
There are two main types of function keys: setting keys that change a common setting in the
current screen, and directional keys that take you to a different screen. In order to easily
differentiate between the two types of keys, we generally use small letters to denote a set
ting key and large letters to denote a directional key. There are a couple of exceptions to
this rule, but not many. Here’s an example from the Main Coupler Screen:
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General Operation 19
Figure 2.3.1—The Main Coupler Screen
Notice that F1, F4, and F5 are written in large letters. They take you to the Menu, ANSI 96, and
Probe Screens, respectively. F2, F3, F6, F7, and F9 are all settings that pertain to the current Main
Coupler Screen.
2.3.2 Customizing the function keys
As described in Section 2.3.1, the functions of F1 through F9 will vary, depending upon the current screen. Most of the time, the functions of these keys in each screen are set at the factory and
cannot be changed. However, the FP40 does allow you to customize the function of several keys.
This allows you to change the FP40 screen to fit your testing needs. Most of these are set in the
FUNCTION KEY DEFIN section of the General Setup Menu.
MAIN F2 & MAIN F3: These settings change the function of F2 and F3 in the Main Coupler
Screen. Usually, you can select from AVG, GAIN, MULTICURVE, and TELECOIL. (These options are
explained in Chapter 3.) The available settings are dependent upon the options on your FP40, so
you may have some additional functions available.
MAIN F4: This setting changes the automated coupler test sequence available from the Main
Coupler Screen. Depending upon the options you purchased with your FP40, you may have only
one choice for this key, or you may have multiple choices. See Chapter 4 for more information on
automated test sequences.
SETUP F2 & SETUP F3: These selections allow you to customize the function of F2 and F3 in the
General Setup Menu. This allows you to adjust functions used in the Main Coupler Screen that you
might not need to change often.
For instance, if you always want to have Multi-Curve turned on in the Main Coupler Screen, you
can have it set to ON in the General Setup Menu, freeing up either F2 or F3 in the Main Coupler
Screen for a more commonly changed function, such as CIC.
20 FONIX FP40 Portable Hearing Aid Analyzer
Note: If you toggle a function with SETUP F2 or SETUP F3, that function will remain in that setting until you explicitly change it back or turn off the analyzer. For example, if you were to: 1)
Choose MULTICURVE for SETUP F2, 2) Turn MULTICURVE ON using the F2 button in the General
Setup Menu, 3) Choose CIC for SETUP F2, then Multi-Curve would remain ON in the Main Coupler
Screen even though it would no longer be the selection for SETUP F2.
F7 DEFINITION: This selection is in a different section in the General Setup Menu than the
previously described selections. This is because MAIN F2-F4 and SETUP F2-F3 all affect the Main
Coupler Screen. F7 DEFINITION, located in the PROBE SETTINGS section of the General Setup
Menu, affects the F7 key in the Main Probe Screen. A setting of SOURC SEL will make F7 in the
Main Probe Screen toggle between the different source types available on your FP40. This is handy
when you’re doing a real-ear test, and you need to be able to quickly switch your source type. For
example, you may want to switch between a composite signal and a digital speech signal. A setting
of SNGL TONE allows you to present a single pure-tone signal to the aid (instead of running an
entire pure-tone sweep).
2.4 Source Types
There are two main types of sources available on the FP40 analyzer: pure-tone and composite.
Three kinds of pure-tone sweeps come standard with the FP40: normal, fast, and short. When you
purchase the Composite Option, you will receive the Composite, Digital Speech ANSI, and Digital
Speech ICRA signals.
The type of source you should choose for a particular test or type of hearing aid depends upon the
signals you have available and the situation. Here is a description of each of the source types and
when you would want to use them.
2.4.1 Understanding Pure-tone signals
A pure-tone sweep is a test involving a progression of pure tone signals presented at a specified
level. When the sweep is complete, the aid’s frequency response at those frequencies is displayed on
the graph (or data column).
There are three types of pure-tone signals: normal, fast, and short.
• NORMAL: Contains 43 different frequencies and only does one sweep before ending the test.
• FAST: Contains 16 different frequencies and continually sweeps through them until you stop
the test. The fast sweep is meant to be used as a real-time continuous signal convenient for
use while adjusting hearing aids. It is an alternative to the composite signal.
• SHORT: Contains 10 different frequencies and only does one sweep. It is primarily used for
testing loud levels in real-ear measurements.
General Operation 21
2.4.1.1 Pure-tone settings
There are several different settings available in the General Setup Menu for pure-tone signals. Here
is an explanation of those settings.
RESET FREQ: The frequency the analyzer returns to when RESET is pressed.
NOISE REDUC: The amount of noise reduction used in pure-tone measurements. See Section
2.4.1.2.
SETTL. TIME: The amount of time each tone is presented before the measurement is made. See
Section 2.4.1.3.
AVG FREQS: The frequencies used with the AVG function that averages the responses of three dif
ferent frequencies. Each frequency set is represented on the screen by the highest frequency in the
set. The sets are:
DISTORTION: The type of harmonic distortion display.
DIST TYPE: Type of harmonic distortion tested. See Section 2.4.1.4.
SWEEP TYPE: Type of pure-tone sweep used in measurements. Choose NORMAL, FAST, or SHORT.
2.4.1.2 Noise Reduction
Noise reduction is used in noisy testing environments. Pure-tone noise reduction takes several measurements at each frequency and averages those measurements together. You can select the amount
of measurements and averaging in the General Setup Menu, in the PURETONE SETTINGS section,
under NOISE REDUC.
Larger noise reduction numbers lead to smoother curves but increase the amount of time it takes to
complete a pure-tone sweep.
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2.4.1.3 Settling Time
When you are measuring with pure-tone sweeps, you are offered a choice of settling times. By this
we mean that the tone source will be continued for a chosen amount of time before the measure
ment is made. This choice is allowed because some hearing aid circuits take a longer time than oth
ers to adjust to changes in amplitude or frequency. If the measurement is made too quickly, an arti
fact in testing will be created. If the measurement takes too long, the test is longer than necessary.
22 FONIX FP40 Portable Hearing Aid Analyzer
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