Description of the display and operating elements KA450

No.

Control element

Display element

Designation

Description

1

X

Transducer selection

Allows the transducer to be changed for tone audiometry and speech audiometry as well as in the SISI test.

Each time the button is pressed, the next transducer is activated, after "External" again "Air receiver". If a transducer output is not activated, it is skipped.

2

X

External

Indicates that the external output is active.

3

X

Free field

Indicates that the free field output is active.

4

X

Bone listener

Indicates that the bonephone output is active.

5

X

Air receiver

Indicates that the air receiver output is active.

6

X

Page selection

Changes the transducer side to which the test signal is applied. If activated, the masking noise set in the setup is output on the opposite side.

If the bonephone output is active, only the masking noise in the transducer set for this purpose is set to the respective opposite side. The test signal always remains on the bone conduction output.

7

X

right

Indicates that the test signal is being applied on the right; the masking signal may be applied on the left.

8

X

left

Indicates that the test signal is being applied on the left; the masking signal may be applied on the right.

9

X

Signal selection

If a test other than tone audiometry is active, tone audiometry is activated when this button is pressed. Within tone audiometry, the modulation of the test signal can be changed from tone (= continuous sine tone) to sweep tone and pulse tone. The properties of the sweep and pulse tones can be changed in the settings menu.

10

X

Pulse

Indicates that the device is in tone audiometry mode with pulse tone modulation.

11

X

Wobble

Indicates that the device is in tone audiometry mode with sweep modulation.

12

X

Sound

indicates that the device is in tone audiometry mode without modulation of the sine continuous tone.

13

X

Language test

Track selection

If a test other than speech audiometry is active, speech audiometry is activated. Initially, the playback of track I is selected.

Depending on the current device settings (Setup à Speech audiometry à Test start), either the internal or external speech test is activated or a selection menu is displayed that allows you to choose one of these modes.

The operation of the two test modes and track selection is explained in the "Speech audiometry" section.

14

X

Language Track 1

Indicates that the speech material is being played back from track 1 of the respective signal source.

15

X

Language track 2

Indicates that the speech material is being played back from track 2 of the respective signal source.

Note: If both indicators light up, the speech material of both tracks is played back. Track I is played back on the test side, track II on the opposite side.

16

X

Anesthetization

The button allows you to switch between the three stunning modes

1. off - no stun noise is generated

2. free - the level of the masking noise is set manually with the level control of the current opposite side

3. synchronous - the level of the masking noise automatically follows the level of the test signal. The initial distance between the test signal level and the masking level can be changed in the settings menu. The distance can be changed during the test using the level control of the current opposite side.

17

X

synchronous

Indicates that the level of the masking noise is currently being automatically adjusted to the test signal level.

18

X

free

Indicates that the level of the masking sound is currently being set manually by the level control on the opposite side.

Remark: If none of the indicators are lit, no deafening sound is generated.

19

X

Fowler

Indicates that the device is in Fowler Test mode.

20

X

Menu

Indicates that the device is in the selection menu for further tests.

21

X

Setup

Indicates that the device is in the settings menu.

22

X

Program selection

Pressing this button first activates Fowler test mode. Pressing it again switches the device from Fowler mode to the selection menu for further tests, then to the settings menu and back to Fowler mode.

23

X

SISI 5 dB

Indicates that the device is in SISI mode with 5 dB level increments.

24

X

SISI 3 dB

Indicates that the device is in SISI mode with 3 dB level increments.

25

X

SISI 2 dB

Indicates that the device is in SISI mode with 2 dB level increments.

26

X

SISI 1 dB

Indicates that the device is in SISI mode with 1 dB level increments.

27

X

SISI

If the device is in a mode other than SISI mode, SISI mode is activated with 5 dB level increments. Each further press of this button changes the level increments from 5 dB to 3, 2 and 1 dB and finally back to 5 dB.

28

X

Arrow up

This button is used for navigation in menus.

29

X

Arrow left

This button is used for navigation in menus.

30

X

OK

This button is used in menus to confirm a selection.

31

X

Delete

Currently without function

32

X

Arrow right

This button is used for navigation in menus.

33

X

Delete

external language: pressing the button resets the counters for correctly and incorrectly reproduced words.

34

X

Talk back

When this button is pressed, the content of the LC display is moved slightly upwards and the current talkback level is shown at the bottom. As long as the button remains pressed, the talkback level can be changed using the two level controls. After releasing the button, the newly set talkback level is retained until the device is switched off. When the device is switched on, the factory-set talkback level is always active.

35

X

Arrow down

This button is used for navigation in menus.

36

X

Counter / Correct

This button is used in language tests to increase the counter for correctly understood words.

37

X

Wrong

This button is used in language tests to increase the counter for misunderstood words.

38

X

Signal (left)

If this indicator lights up, a signal is being output on the left channel.

39

X

Signal (left)

Pressing this button interrupts the current test signal, regardless of the side on which the test signal is output. The deafening signal is not affected by the interruption.

40

X

Save (left)

Currently without function in "stand-alone" operation. May be used as a data transfer button in conjunction with audiometry software.

41

X

Microphone

Intercom microphone. If no external microphone is connected, the signal that is recorded via this microphone is transmitted to the patient via the currently set transducer at the set intercom level when the "Intercom" button (58) is pressed.

42

X

Level control (left)

Level control for the signal that is applied to the patient's left ear. It depends on the side currently set whether this is the test signal or the masking sound.

43

X

Matrix (left)

Level and frequency indication for the signal on the patient's left ear.

44

X

Net

The "Mains" display lights up to indicate that the appliance is switched on.

45

X

Audiogram form-

centering aids

These two cylindrical screw heads are used to center audiogram forms correctly over the matrix in accordance with DIN 45 627. 

46

X

Matrix (right)

Level and frequency information for the signal in the patient's right ear.

47

X

Level control (right)

Level control for the signal that is applied to the patient's right ear. It depends on the side currently set whether this is the test signal or the masking sound.

48

X

Patient signal

The illumination of this indicator shows that the patient has pressed the patient button.

49

X

Save (right)

Currently without function in "stand-alone" operation. May be used as a data transfer button in conjunction with audiometry software.

50

X

Signal (right)

If this indicator lights up, a signal is being output on the right channel.

51

X

Signal (right)

Pressing this button interrupts the current test signal, regardless of the side on which the test signal is output. The deafening signal is not affected by the interruption.

52

X

Frequency down

Selects the next lower frequency for tone audiometry, SISI and Fowler. If the button is pressed at 125 Hz, 1000 Hz is selected next. With each frequency change, the level of the test and masking signal is reduced by the value stored in the settings menu.

53

X

Frequency high

Selects the next higher frequency for tone audiometry, SISI and Fowler. If the button is pressed at 8000 Hz, 1000 Hz is selected next. Each time the frequency is changed, the level of the test and masking signal is reduced by the value stored in the settings menu.

54

X

VU meter scale

Scale for displaying the level of input signals in the settings menu à VU meter.

55

X

LC display

Graphic display on which test parameters, menus etc. are shown.

56

X

Inverter

This button is only active during audiometry. It can be used to change the behavior of the interrupter buttons. The interrupter function is always either in the "normal" or "inverse" position.

If the inverter is in the "normal" position (display 62), the test signal is given in the tone audiometry as long as the signal right or left interrupter buttons (51, 39) are not pressed. The test signal is muted by pressing the interrupter buttons.

If the inverter is in the "inverse" position (display 61), the test signal is muted in audiometry as long as the signal right or left interrupter buttons (51, 39) are not pressed. The test signal is activated by pressing the interrupter buttons.

57

X

> 100 dB

This button is used to unlock the level lock.

If an attempt is made to set a level above 100dB_HL If you try to adjust the level, this will initially fail and the message "Level lock" will appear on the LC display. To set the level above 100 dB_HL If you want to increase the level above 100 dB, you must first press this button. The message "Level lock" will then disappear from the display and the red warning indicator "> 100 dB" (60) will light up. The level can then be increased up to the maximum level physically possible for the respective converter or up to a maximum of 120 dB_HL be increased.

If the signal level falls below 80 dB_HL is lowered, the unlocking of the level lock is automatically canceled.

The level lock can only be activated from a set signal level of 80 dB_HL be activated.

58

X

Speak up

By pressing the Talk button, the examiner can speak directly to the patient via the built-in microphone (41) or an externally connected microphone. The intercom function is active as long as the button is pressed. The test signal and the deafening noise are suppressed while speaking. When the button is pressed, the content of the LC display is moved upwards and the intercom level is then shown at the bottom edge. This can be changed using the level controls as long as the button is pressed. The intercom level is set to its factory preset value each time the intercom button is pressed.

Warning! Always ensure that there is sufficient distance between the microphone and the selected transducer. Only increase the volume carefully. Otherwise this can lead to strong feedback (whistling sound).

59

X

Speak up

This indicator lights up as long as the intercom function is active and therefore the signal from the intercom microphone is transmitted to the patient rather than the test/anaesthetic signal.

60

X

> 100 dB

This display flashes briefly when the level lock (57) is reached and lights up continuously when the level lock (57) is unlocked.

61

X

inverse

This indicator lights up when the interrupter function is in the "inverse" position. A detailed description of the breaker function can be found in the description of the button (56).

62

X

normal

This indicator lights up when the interrupter function is in the "normal" position. A detailed description of the breaker function can be found in the description of the button (56).