Welch Allyn GSI 38, Service Manual

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Transducer Stimulus Tone
Frequency (HZ)
Contra (Insert Phone)
(in HA-l Coupler)
IPSI
(in HA-l Coupler)
Contra (Insert Phone)
(in IEC 711 Coupler)
500 1000 2000 4000
6.0 1.0 6.0 3.0
7.0 4.5 2.0 3.5
9.5 5.5 11.5 15.0
Rise/Fall Time: 5 to 10 msec
Pressure: Automatically set to the pressure of peak compliance 20 daPa.
Reflex Determination: Minimum compliance change 0.05 cm 3
Test Time: Approximately 2 -12 seconds, depending on number of test frequency
selections and if tymp only test. (four maximum)
Probe LED indicators:
Green blinking: Ready to test
Green steady: Test in progress
Orange steady: leak or other error
Yellow steady: Occlusion
AUDIOMETER
Test
Stimulus
Pure Tone Specifications: A pure tone is the only stimulus source for this
audiometer.
Discrete Frequencies: 125, 250, 500. 750, 1000, 1500, 2000, 3000, 4000, 6000
and 8000 Hz.
Equivalent Hearing Threshold Levels. in
dB
SPL for TDH 39 Earphones:
Frequency (Hz) 125 250 500 750 1000 1500
Reference Threshold (dB)
45.0 25.5 11.5 7.5 7.0 6.5
Frequency (Hz) 2000 3000 4000 6000 8000
Reference Threshold (dB)
9.0 10.0 9.5 15.5 13.0
Frequency Accuracy: +/- 3%
Total Harmonic Distortion (From 125Hz to 3000 Hz, measured Acoustically at the
Maximum HL, measured electrically at 4000 & 6000 Hz) < 3%.