Welch Allyn GSI 38, Руководство по обслуживанию

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AUDIOMETER SPL OUTPUT LEVEL CALIBRATION
1) Use the
to position
the cursor on the 38 display at XDUCER
STIM CAL.
2) Press the Key to enter the XDUCER STIM
CAL
MODE.
The display should now indicate:
XDUCER STIM CAL
40.0 dB
1 2 5 Hz
R
NOTE: Tone Bar is OFF
or Inactive
40.0 dB Indicates the Current Hearing Level (HL) selected.
125 Hz Indicates the Current Frequency (Hz) selected.
R Indicates the Current Transducer selected.
Indicates a Steady Tone Presentation
The Tone Bar is active in this mode and serves a dual function. When the Tone Bar
is OFF or inactive the current hearing level is displayed as shown above.
When the Tone Bar is pressed ON or active the stim on indicator
will appear on
the display and the 40.0 dB (HL) indicator will update to the ANSI Standard Reference
Threshold Level (RTL) measured in Sound Pressure Level (SPL) for the selected
frequency and hearing level.
Example: 40.0 dB (HL) at 125 Hz (Freq) will update to 85.0 dB SPL
when the Tone Bar is depressed.
Given: The ANSI Standard (RTL) correction value for 125 Hz at 0 HL is
equal to 45.0 dB SPL.
Therefore: At 40 dB HL which is 40 dB SPL higher that 0 dB HL the output for
125 Hz will equal 85.0 dB SPL.
For 125 Hz
ANSI Standard RTL for 0 dB HL
45.0 dB SPL
(+)40 dB HL =
(+)40.0 dB SPL
40 dB HL 85.0 dB SPL