otometrics Madsen ZODIAC 901, Руководство пользователя

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3.4.3 DAILY CALIBRATION
Annual
Recalibration Your ZODIAC 901 is delivered to you fully calibrated, and should be re-
calibrated annually by suitably qualified personnel, using the appropri-
ate equipment. Your instrument may have been configured by means of
ZODICON™ to remind you when this period has expired.
Test Report Your ZODIAC 901 is dispatched from the factory in Denmark together
with a Test Report (Calibration Certificate). The Test Report specifies
which transducers have been calibrated (i.e. those which have been sup-
plied together with the instrument), according to which standards, and
what equipment was used for calibration. Results are listed for each
transducer at all standard frequencies.
In general, the instrument is calibrated in dB SPL or dB HL using the
stated reference equivalent thresholds; dB HL are related to sound pres-
sure levels, db SPL = dB re 20
m
PA. (1 cc = 1 ml).
Note that calibration has only been performed on the supplied trans-
ducers! If you wish to use any other transducer for testing with the
ZODIAC 901, please contact your local Madsen distributor first.
However, since the weather and barometric pressure vary from day to
day, the probe measuring system should be calibrated on a daily basis in
order to achieve the greatest possible measurement accuracy.
Softkey 3
With the ZODIAC 901, this procedure is very quick and easy to perform
(maximum 15 seconds); just press
Softkey 3 from the Main Menu to ac-
cess the screen shown in Fig.3.4:
Softkey 1 If provision for calibration with a second Precision Cavity having a dif-
ferent volume from the default has been programmed using ZODI-
CON™,
Softkey 1 may be used to toggle between the two cavities. The
volume of the cavity selected is shown in the small box on the left of the
display.
Softkey 2 Insert the probe into the 2.0 cc (= 2.0 ml) Madsen Electronics Precision
Cavity located in the left side of the ZODIAC 901’s cabinet. (Do not in-
sert it into the Madsen Electronics Ear Simulator.) Press
Softkey 2 (or
the Start/Stop Button on the Probe) to start the calibration. The Status
lamps on the Front Panel and the Probe light steadily green during cali-
Operation Manual 23
GN Otometrics GENERAL DESCRIPTION Chap. 3
ZODIAC 901 Middle-Ear Analyzer
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3.4
Fig.3.4