GSi TYMPSTAR 1, Руководство по обслуживанию

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Specifications
Stimulus Signal ON/OFF Ratio: >70 dB
Presentation Control OFF mode signal level: <20 dB SPL
Signal To Noise Ratio: >70 dBA
Measured with disabled probe signal and “A” weighting for noise
measurement .
Residual noise: <25 dBA SPL
(Stimulus Present switch in OFF position)
Unwanted Acoustic Probe Signals: <60 dBA
Measured while pump is operating and probe tone is disabled. Measure it
with “A” weighted filter in “SLOW” Time mode. The noise in normal
operating mode will not effect the immittance measurement accuracy.
Signal separation between Ipsi and Contra channels; all frequencies: >70 dB
(Measured at the probes with the “ON” channel set to 90 dB)
Leaked signal: <20 dB SPL
The radiated acoustic noise from the instrument (with reflex stim off) when
measured at 1 meter from the instrument, shall be: <50 dBA
(“A” weighting and “SLOW” averaging)
Temporal Specifica- Steady State Stimulus
tions of Stimulus Initial Delay (elapsed time from present bar activation to 10% stimulus
Presentation amplitude): < 100 msec
Terminal Delay (elapsed time from present bar deactivation to 90% stimulus
amplitude): <100 msec
Rise time: 7.5 ± 2.5 msec
Fall time:
7.5 ± 2.5 msec
Multiplexed Stimulus (Used in Reflex Threshold test mode)
Period data for frequencies: 250 and 500 Hz:
Period 124 msec
Stimulus on time 44 msec
Stimulus off time 62 msec
Rise and fall time 18 msec
Period data for all other frequencies:
Period 115 msec
Stimulus on time 44 msec
Stimulus off time 53 msec
Rise and fall time 18 msec
Temporal Spec. Accuracy: ±10% or 5 msec, whichever is greater
GSI TympStar Version 1 and Version 2 Service Manual 2 - 5