In Left+Right stimulus situations, this knob controls the Right stimulus
Hearing Level. It may also be used as a potentiometer control during
sensitivity adjustment of input levels.
Potentiometer
Frequency
This rotary knob controls frequency in pure tone audiometry. Each click of
the knob increases or decreases the frequency by one increment (the
ranges are listed below).
# 20
Turn to the left to decrease and to the right to increase frequency. Frequency
may be read off the lower line on the left of the display.
When “Patient” is selected from the Select Function Menu, this knob is used
for selecting numerals and symbols when entering the patient's I.D. number.
Patient I.D.
Number Entry
This knob may also be used as a potentiometer control during sensitivity
adjustments of Input levels.
Potentiometer
Range for Phone and Free Field: 125 - 8000 Hz.
Range for Bone Vibrator: 250 - 6000 Hz.
Tone Switch
This bar presents stimulus tone via preselected channel or interrupts tone if
the audiometer is in Reverse mode (see below). The interrupter bar controls
attenuator output.
# 12
Tone-On indication is displayed on the green stimulus LED to the left of the
display.
Reverse
This button toggles the Tone Switch between Tone Switch mode and
Interrupter mode. Used mainly in speech audiometry to interrupt taped input.
# 15
Left/Right Shift
Pressing this button while in Test Mode changes the stimulus to the opposite
ear, if possible. If masking is selected, this signal will be shifted too.
# 10
If Left+Right is selected, only the HL settings will be exchanged.
In bone conduction tests with Air masking, pressing this button changes the
routing of the masking signal from the right ear to the left ear, and vice versa.
A click will be heard each time the masking signal is changed.
Change Masked
Ear in Bone Con-
duction Tests
Menu
This pushbutton returns you to the top of the Selection Tree displaying either
the Select User Test Menu or the select Function Menu depending on which
“branch” of the Selection tree has previously been selected. Pressing this
pushbutton toggles between the two menus.
# 11
Always press
MENU
to exit Test Mode.
MENU
MIDIMATE 622 OPERATION MANUAL
5. Operating in Test Mode
22
