Operation; Preliminary Adjustments; Calibration - BRUEL & KJAER 1022 Instructions And Applications

4. OPERATION
PRELIMINARY ADJUSTMENTS
Before the instrument is used check the voltage selector on the rear panel
is set to the correct line voltage. If not, remove the central fuse and adjust
with a small coin or screwdriver.
A. CALIBRATION
1. Switch on and allow 1 minute to warm up.
2. Set MODULATION FREQUENCY and COMPRESSOR SPEED to "Off".
3. Set main scale pointer to the frequency of the mains supply (e.g. 50 or
60 Hz) checking that the frequency increment scale is set to zero.
4. Set the meter deflection to higher than centre scale reading with OUT-
PUT LEVEL knob.
5. Press POWER FREQUENCY BEAT button and hold "in". At the same
time slowly adjust the FREQUENCY SCALE ALIGNMENT FINE knob
until a large fluctuation registers, slows up, and practically ceases on the
meter dial.
6. Set main scale pointer to 20Hz and subtract 20Hz with FREQUENCY
INCREMENT knob. If the meter deflection drops to zero then the B.F.O.
is·calibrated. If not, continue to point 7.
7. If the meter deflection does not drop to zero, adjust FREQUENCY SCA-
LE ALIGNMENT COARSE with a screwdriver until the meter deflection
does.
8. Reset the main scale pointer to the frequency of the mains supply. Reset
frequency increment scale to zero. Make a final adjustment with F RE-
QUENCY SCALE ALIGNMENT FINE to obtain the exact position of.
"slow beat" as in point 5. The B.F.O. is then calibrated.
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