BG 805 981 BE (0201) QMG422.oi
39
Time constant of the analog filter for the electrometer signal
FILTER
With detect-TYPE:FARAD, SEM and EXTERN
18 µs ... 800 ms
Manual setting for special requirements. Choose a filter value that is
appropriate to the measuring speed.
AUTO
The analog filter is automatically set as follows:
SPEED
[ms/u]
DWELL
[ms]
FILTER
SPEED
[s/u]
DWELL
[s]
FILTER
0.5 / 1
18 µs
0.2 / 0.5
8 ms*
2 / 5
85 µs
1 / 2
40 ms**
10 / 20
400 µs
5 / 10
180 ms
50 / 100
1.7 ms
20 / 60
800 ms
*) Minimum value in
RANGE
10
-11
**) Minimum value in range
RANGE
10
-12
With
amplif-MODE:AUTO
or
AUTO-D
an optimum filter is automatically used.
With
mass-MODE:SAMPLE
(MID mode) a fast filter results in faster settling times
which means that
PAUSE
can be shortened.
Signals above the maximum range of ±10.24 V (e.g. noise) are clipped. In this case
the subsequent processing (e.g. averaging) may possibly be incorrect. In critical
cases the electrometer signal must be analyzed with an oscilloscope or with
Quadstar 422 in
mass-MODE:SCAN-N
so that it can be optimized.
With
mass-MODE:SCAN-F
the FIR filter provides for additional filtering.
See
TEST-SERVICE
Starting mass number of the mass scan
FIRST
With
mass-MODE: SCAN,
STAIR
and
PEAK
0.00 ... max. 2047.99
The maximum value depends on the mass range
The mass number is displayed as a decimal value; internally steps of
W
u are
used. At high
SPEED
the resolution decreases to
V
or
+
(
→
12).
See
V3
See
TEST-SERVICE
FUNCT
Measurement cycle mode, can only be changed in
halt
condition
CYCLE
Normal measurement operation
ADJUST
Adjustment to peak top with
mass-MODE:SAMPLE
→
6.12
OFFSET
Offset correction of the EP 422
→
47
GAIN
With
detect-TYPE:EXTERN
×1, ×10, ×-1, ×-10
Post-amplification factor for the Extern signal
RESET
Load standard parameters (according to
config-SYSTEM)
→
66
FACTORY
Load standard parameters set by pressing
SURE ?
Confirm with
, the old parameters are irretrievably lost!
See
V1
FILTER (amplif)
FILTER (config)
FIRST (mass)
FOCUS (v1...v6)
F.S.+/ F.S.– (config)
FUNCT (cycle)
GAIN (amplif)
INIT (config)
IONREF (v1...v6)