Sencore FE149 - Page 11

DISASSEMBLY INSTRUCTIONS
If the FE149 is tobe removed from its case for service or recalibration, the battery
door must be removed first. То do this, remove the two screws holding this door
on the backof the case. Then remove the four screws holding the front panel to the
case, two on the bottom of the panel and two on the back of the case. Tilt the top
forward slightly and pull the panel from the case. This will expose the PC boards
and chassis for calibration or service. Generally, no further dismantling is nec-
essary for service work, as the bottom of the circuit board is accessible and the
circuit board on the bottom holds only the range resistors. АП the calibration con-
trols will be found on the top board with the exception of the low ohms cal control
which is on the range board.
If it should be necessary to separate the two boards for parts access, remove the
phillips screws holding the range РС board. Push therange assembly sideways until
the push knobs will clear the edge of the panel on one side, then slide the assembly
to the opposite side until it is free of the panel. The assembly can then be moved
for best convenience.
9 reassemble the FE149, simply reverse the procedure.
CALIBRATING THE ЕЕ149
The FE149 canbe recalibrated quickly andeasily ifand when it becomes necessary.
First, remove the unit from its case. See DISASSEMBLY INSTRUCTIONS. This
will expose the two printed boards and the calibration controls. If a complete re-
calibration is to be done, follow the steps in the order below. If only a touch up of
the AC or DC ranges is tobe made, be sure to check the AC and DC balance. Cal-
ibration is affected if balance is off. As a preliminary to any calibration, set the
mechanicalzero on the meter to zero. Dothis whenthe meter is innormaloperating
position and set up for 500 milliamps DC current test.
DC BALANCE: Depress the plus DC volts Function button and the 1500 volt Range
button and slide the power switch to on. (Nodifference will be notedif the ЕЕ149 is
operated from the AC line or battery unless the battery is down. Tocheckthe battery,
simplydepress the BATT button onthe Function switch and read the battery condition
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