GSi TYMPSTAR 1, Service Manual

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Calibration
The flexibility of the version 2 results in a slightly more involved calibration for Ipsi
and Contra outputs. The Ipsi transducer must be calibrated on Ipsi and Contra
channels. Likewise, the Contra Phone must be calibrated on Contra and Ipsi chan-
nels.
External Input The voltage requirement for external inputs is 0.5 RVMS to 1.0 RVMS. When set,
Calibration this stimulus cannot be altered (voltage or frequency) or the outputs will lose their
calibration.
The frequency of the external stimulus must be carefully selected for the probe tone
with which it will be used. If the stimulus is too close to the probe tone frequency, a
stimulus artifact will occur during Reflex tests. Always check for stimulus artifact by
presenting the maximum HL in a hardwall cavity and note if there is any Y axis
deflection.
The external input will be calibrated with default data when it leaves the factory. The
default data will assume that a 1.0 VRMS, 1kHz voltage is applied at the input and
that the output is calibrated in SPL (i.e., 80 dB dial reading will provide 80 dB SPL
of 1 kHz output).
Click Calibration GSI recommends that click calibrations be performed with the Sound Level Meter
set to the Peak Hold and Linear Mode. This will insure that the repetition rate will
have no effect on the measurement.
Clicks will be calibrated in Peak Equivalent SPL at GSI. That is, for a setting of 80
dB HL, the Peak Hold SPL’s will be the following:
• IPSI 88.5 dB Peak Hold SPL
• CONTRA 85.5 dB Peak Hold SPL
NOTE
Refer to the Click Stimulus section of the Version 2 product specifications
for more detailed transfer data.
If Peak Hold is not available on the SLM, use linear (flat) response and fast detector
(RMS) and set the click to the following SPL’s for the two transducers:
• IPSI at 80 dB HL set to 74.5 dB SPL
• CONTRA at 80 dB HL set to 71.5 dB SPL
GSI TympStar Version 1 and Version 2 Service Manual 4 - 55