Welch Allyn Micro Tymp 1, Service Manual

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Section 2.4 Service
MT 1 CALIBRATION PROCEDURE
Step 4 CONTINUED....
ORIGINAL PCB DISTORTION TEST:
SET UP:AS PER SOUND LEVEL TEST, EXCEPT FOR THE CENTER FREQUENCY OF THE FILTER.
THE MEASURED LEVELS SHALL NOT EXCEED THOSE SHOWN BELOW:
FILTER CENTER FREQ. (Hz) MAXIMUM SOUND LEVEL (dB)
500 ...................................................... 55
1000 ...................................................... 49
2000 ...................................................... 39
ORIG PCB DISTORTION TEST LEVELS (from A-00848,sheet 1 of 2, note 5)
PCB+ DISTORTION TEST:
THE MEASURED LEVELS SHALL NOT EXCEED THOSE SHOWN IN AT LEAST ONE OF THE THREE
MAXIMUM SOUND LEVEL COLUMNS BELOW.
NOTE: WHEN YOU START THE TEST AT 500 Hz AND MEASURE A SOUND LEVEL IN ONE OF THE
COLUMNS BELOW, R E M A I N IN THAT PARTICULAR COLUMN FOR READINGS AT 630 Hz
AND 1000 Hz. DO NOT SWITCH TO ANOTHER COLUMN.
1/3 OCTAVE FILTER MAXIMUM SOUND LEVEL (dB)
CENTER FREQ. (Hz)
500 ................................................... 39.3 ................ 45.0 ............... 47.6
630 ................................................... 56.0 ................ 54.3 ............... 51.3
1000 ................................................... 38.3................ 40.0 ............... 45.5
PCB+ DISTORTION TEST (from A-01785, table 5)
...........................................................................
NOTE: After this point, the tests for Original PCB and PCB+ are identical.
Step 5
PERFORM PNEUMATIC SEAL PRESSURE TEST
(taken from A-01785 note#3. Good for both Original PCB and PCB+)
CONNECT UNIT TO A MANOMETER. WITH THE CALIBRATOR IN THE CALIBRATE MODE,
DEPRESS “UP” BUTTON TO LATCH THE VALVE IN CLOSED POSITION. AT PRESSURES OF
+300 dapa AND -300 daPa, THE LEAK RATE SHALL BE LESS THAN 12 daPa OVER A 5 SEC-
OND PERIOD. TO RESET THE VALVE, FLIP THE CALIBRATE/RUN SWITCH TO THE RUN
POSITION FOR APPROXIMATELY ONE SECOND. THEN FLIP THE SWITCH BACK TO THE
CALIBRATE POSITION.
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