Warning
0
Always carry out an adjustment procedure completely and in the
order in which it is presented.
If the HP 81 12A is very badly out of adjustment, turn
A 1 R4 1 3
fully
clockwise and all other adjustment potentiometers to their mid
position. Then carry out
all
the adjustment procedures.
Some of the adjustment procedures may require components to be
changed. These components are summarised in Table 9-1 .
Do not change a component while power is connected to the
instrument.
Figure 9-8 and Figure 9-9 at the end of the chapter show the
locations of all the adjustment points in the instrument.
Table 9-1. Adjustment Procedures - Changeable Components
Procedure
Reference
Range
Description
Overshoot/ A1C409
0 pF (open) - 3.3 pF Increasing the value decreases transition times and
Transition
increases overshoot in Fixed mode
Times
A1C414
as used
Increasing C414 decreases overshoot at amplitudes
� 14 v
A1C501
27 pF
Pulse performance at ampl. 0.1 V - 0.99 V
A1C502
120 pF
Pulse performance at ampl. 1 V - 9.99 V
A 1C528
1.5 pF
Pulse shape
A1C532
0 pF (open) - 33 pF Increasing C352 decreases transition times and
decreases overshoot in Fixed and Linear mode
A1C535
47 pF
Pulse shape
A1C541
0.01 pF
Pulse shape
Timing
Period
A 1C200
22 pF
Range capacitor
A1R2 1 1
2 15n
Bias adjustment
A2VR2
open or 4.3 V
Both influence linearity of
and
A2R62
open or 5 1 . 1 kn
Period Generator
A2R2
3.83 kn
used to get A2R4 (PER 1 ms Adj .) to it's mid
range
A2R53
3.83 kn
used to get A2R3 (PER 20 ms Adj .) to it's mid
range
9-2 Adjustment Proc�dures
Summary of Contents for 8112A
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Page 290: ...R B c R3 BD RY M I CROPROCESSOR 1 2 3 FIGURE 1 0 7 8 ...
Page 294: ... 8 X2l 2 X2 Figure A 1 Mechanical Parts 1 A 2 Replaceable Parts ...
Page 295: ...MP MP3 MP MP2 MP4 MPS MP 1 2 MPS MP MP I B ElElElEl Replaceable Parts A 3 ...
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Page 378: ...Figure B 14 Mechanical Parts 1 B 44 Backdating ...
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