Frequency Selector; Present Bar; Extended Range Pushbution - Welch Allyn Grason-Stadler GSI 17 Series Service Manual

4.5.3 FREQUENCY SELECTOR

This control operates as
frequency to be calibrated.
and they can be calibrated in any sequence.
4.5.4

PRESENT BAR

Present Bar controls the presentation of the
The
a push ON/push OFF manner.
operates in
while the stimulus is off, the stimulus will be
operated
on and remain on until the Present Bar is operated a second time.
The stimulus will actually be turned ON or OFF when the
Bar is pressed.
4.5.5
HL DIAL
This control performs the dual function of selecting the HL
1.
level at which the calibration is being performed and of
adjusting the output level of the transducer.
While the stimulus is off, the HL selector will select the
2.
Calibration HL level (Cal HL).
up by 5 dB for each clockwise step of the selector and down
by 5 dB for each counter clockwise step.
the Calibration HL level the transducer output level
(attenuator position) will be recalculated using the current
calibration data stored in the EEPROM.
of the calibration HL will be from the nonextended (+10 dB
range) maximum HL limit to 20 dB below the limit.
of the selector to select levels outside of this range
invalid.
limit and the HL display will be flashed.
While the stimulus is on, the HL selector (dial) will adjust
3.
the transducer output level to allow the SPL level to be
adjusted to the required SPL level on the sound level meter.
The output level will be adjusted up by 0.5 dB for each
clockwise step of the selector and down by 0.5 dB for each
counter clockwise step.
according to the HL selector by directly setting the
attenuator position.
positions outside of the instrument range will be invalid.
The attenuator position will be adjusted within the limits
and the displayed SPL value on the HL display will be
flashed.
4.5.6 EXTENDED RANGE PUSHBUTTON
This pushbutton is used to store the transducer SPL
data into EEPROM.
stored, the EEPROM checksum will be updated
Response LED will be turned on for 2 seconds.
data can not be stored successfully, the word
flashed on the HL display and the previously displayed SPL value
in the Normal
All frequencies must be
When this occurs the level will default to the
Operation of the HL dial to select
After the calibration data is
Mode to
If the Present
The level will be adjusted
For each change in
The allowable range
The output level is changed
and
If the calibration
select
the
calibrated
stimulus.
It
Bar is
turned
Present
Operation
are
calibration
successfully
Patient
the
"CAL"" will be