Casella CEL CEL-281 User Manual
Page 129
18.
Using a slim screwdriver, reach through the hole in the upper
circuit board and adjust the trim potentiometer on the lower
board (shown in Figure 23) until the display indicates 114.0 dB.
The analog section has now been trimmed for the replacement
microphone.
19.
Switch the calibrator OFF.
20.
Remove both calibrator and coupler from the microphone.
21.
Remove the keypad from the dosimeter.
22.
Press the dosimeter ON/OFF switch in once to unlatch it and
switch the instrument OFF.
23.
Remove the dosimeter battery pack.
24.
Carefully replace the plastic insert around the ON/OFF switch
and multi-pin connector.
25.
Position the microphone cable in the cut-out provided for it in
the instrument rear cover.
26.
Replace the front cover, first carefully engaging it around the
plastic insert.
27.
Re-fasten the four screws, but leave them loose.
28.
Insert the cover for the connector and controls into its guides.
29.
Tighten the four screws.
The instrument is now ready for operation using the replacement micro-
phone.
Page 120 - CEL-281 Operator's Handbook
Technical Information_