audioscan verifit User Manual Download

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Verifit

User's Guide Version 4.8

November 2016

6. To measure another set of 5 input/output curves, click another [Curve #].

7. To summon a cursor to determine curve values, position the mouse pointer on a graph area and click the left

mouse button. Click again to turn it off.

NOTE:

Noise in the test area may cause erroneous results at low input levels (particularly at 250 and 500 Hz).

Ensure that the test box is well sealed and ambient noise is low.

ANSI telecoil terminology

The Verifit 2 test chamber contains a telecoil test loop and the tele-test handset contains a telephone magnetic
field simulator (TMFS), both of which meet the requirements of ANSI S3.22 and enable the measurement of
coupler SPL produced by a hearing instrument with a telephone pickup coil. ANSI uses the following terms in
telecoil testing:

RTG

(reference test gain) is the average gain measured with the gain control in the reference test setting. See

ANSI S3.22-2003 and ANSI S3.22-2009 facts.

TMFS

(Telephone magnetic field simulator). A 38.4-mm diameter coil spaced 16.5 mm below a test surface

driven by a specified test signal. Intended to simulate a telephone handset receiver.

SPLITS

(Coupler SPL for an inductive telephone simulator). SPL developed in a 2cc coupler by a hearing

instrument with the gain control in the RTS when the input is the magnetic field generated by a TMFS.

HFA (or SPA) –SPLITS

. Average of the SPLITS at HFA or SPA frequencies.

RSETS

(relative simulated equivalent telephone sensitivity) is calculated as HFA SPLITS minus (RTG + 60). A

positive RSETS indicates greater output when using the telephone than when using the microphone.

SPLIV

(Coupler SPL in a vertical magnetic field). SPL developed in a 2cc coupler by a hearing instrument,

positioned as worn, with the user gain control in the RTS when the input is a 31.6 mA/m vertical magnetic field.

HFA – SPLIV

. Average of the SPLITS at HFA frequencies.

RTLS

(relative test loop sensitivity) is calculated as HFA SPLIV minus (RTG + 60). A positive TLS indicates

greater output when listening in a room loop than when using the microphone.

ANSI telephone simulator (TMFS) test

WARNING

: The included magnet may effect some medical or electronic devices. Keep magnet at least 5cm

(2in.) from implantable devices and other magnetically sensitive devices.

WARNING

: Keep magnet out of reach of children and pets. If a magnet is swallowed seek immediate medical

attention.

ANSI S3.22 requires that the gain control be set to RTS before running this test. The reference test gain (RTG)
is required in order to calculate the or RSETS. The easiest way to meet both requirements is to run a [ANSI] or
[ANSI / IEC] test before running this test. See ANSI 2003 and ANSI / IEC tests. The tele-test handset comes
with a small magnet attached that may affect implantable devices. See How to Avoid Undesirable Side Effects.

1. First, complete an [ANSI] or [ANSI / IEC] test,

2. Click the right mouse button to raise the home menu, then select [Telecoil].

3. Set the aid to "T" (telecoil input).

4. Click [Start TMFS test]. Test setup instructions are displayed.

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