HEWLETT PACKARD (HP) 4342A
Instrukcja Serwisowa

Model 4342A

Section Figure

TTT

3-6

Mechanical

zero

adiustment

The meter is properly zero-set when the pointer sets exactly over the zero calibration scale mark and the instrument is in its normal operating environment. To check the meter mechanical zero, turn the instrument off and allow 30 seconds to completely deenergizethe z strument. To obtain maximum accuracy and mechanical stability, if the meter is not over zero, zero-set the meter as follows: a. b. Rotate meter pointer adjustment screw @ clockwise is moving toward zero in an upscale direction. Continue rotating screw clockwise and stop exactly at zero. If the pointer overshoots, the adjustment screw clockwise to do steps until meter

when pointer is continue rotating a and b once again.

C.

When the pointer is exactly over zero, rotate adjustment screw slightly counterclockwise to relieve tension on pointer suspension. If pointer moves off zero, repeat steps a, b and c, but rotate less counterclockwise. zero adiustment

Electrical

The meter pointer should set exactly over the zero scale mark when instrument is turned on and nothing is connected to measurement terminals. Turn the instrument on and allow at least 15 minuts warm-up time to let the instrument reach a stable operating condition. If meter pointer is not over zero, zero-set the meter as follows: a. b. Set FREQUENCY RANGE selector 001) and Q RANGE@ to 1000. Adjust pointer rear panel is exactly @to 22k - 70k (10k - 32k for so that the meter Option

METER ZERO ADJ control@ over zero.

Figure

3-6.

Zeroing

Procedure

(sheet

2 of 2).
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