Welch Allyn GSI 38, Service Manual

Page: 44 / 96

CUSTOM RTL CAL
This mode is used primarily if a customer wants to calibrate using transducers other
than TDH-39P earphones. This mode allows the technician to program different
RTL values to be displayed when calibrating using the XDUCER STIM CAL MODE.
Once programmed, the Custom RTL values will be displayed each time the
XDUCER STIM CAL MODE is entered. The range of allowable RTL's is -5 dB to
63.5 d B A # sign will appear next to the dB HL indicator on the display when
Audiometry Mode is selected to indicate to the customer that Custom RTL values
have been programmed. To return to the ANSI Standard Values and extinguish the
# sign, the technician must load Audiometry Default Calibration Data.
1)
Use to position the cursor at Custom RTL Cal on the
display.
2) Press the Key to enter the Custom RTL Cal Mode.
3)
Press to select the desired frequency.
4)
Adjust the dB HL dial to achieve the desired RTL value.
5) Store the value into memory by pressing the Key.
6) Repeat for all desired frequencies.
7)
Press
NOTE:
the Key to return to the Main Calibration Menu.
Adjusting the Custom RTL values has no effect on the earphone
output level. After storing the Custom RTL's the technician
must calibrate to the appropriate levels using the XDUCER STIM
CAL MODE.
PROBE TONE/MIC CAL
Use to position the cursor at the Probe Tone/Mic Cal
Mode position.
2)
Press the PROG Key to enter Probe Tone/Mic Cal Mode. The display will
update to the following “flashing” display.
PROBE TONE/MIC CAL 1.1
ECV SLM
At this point place the probe in the 2 cc coupler on the Sound Level Meter.