Stanford Research Systems SIM983, Руководство по эксплуатации и обслуживанию

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1 – 4 Getting Started
If one of [gain ] is pressed and held, the gain is continuously ad-
justed. The rate of the adjustment increases as the button is held. If
the absolute value of the gain is being lowered, the rate of the adjust-
ment changes as
| G | crosses 1.00, and possibly again as | G | crosses 0.10.
If both [gain ] and [gain ] buttons are pressed at the same time, the
resetting gain
absolute value of the gain is reset to 1.00. This action does not change
the polarity.
Pressing one of [gain ] and [polarity] at the same time has a special
meaning. This press initiates autocalibration (Section 2.2).
1.2.3 Offset
The input-referred voltage o
ff
set V
ofs
can be set to a value
between − 10
.
00 V and
+
10
.
00 V
.
Its value, in volts, is shown on
the second line of displays on the front panel of the amplifier.
To increase or decrease the o
ff
set, press the button [o
ff
set ]
or the button [o
ff
set ]. Unlike the gain, the “up” and “down”
buttons adjust the o
ff
set, not its absolute value. Thus, for
example, pressing [o
ff
set ] when V
ofs
=
− 5
.
49 V makes
V
ofs
=
− 5
.
48 V
.
If [o
ff
set ] is pressed when V
ofs
= +
10
.
00 V
,
the
press has no e
ff
ect. If [o
ff
set ] is pressed when V
ofs
=
− 10
.
00 V
,
the
press has no e
ff
ect.
Between the values − 2
.
00 V
<
V
ofs
< +
2
.
00 V
,
the o
ff
set is selected
with 0
.
001 V resolution; the position of the decimal point on the front-
panel displays is shifted to the left. Although the resolution is 0.01 V
for
| V
ofs
| ≥ 2
.
00 V
,
the accuracy of the o
ff
set is still ± 1 mV ± 0
.
02%
.
Thus, for example, setting V
ofs
=
− 5
.
48 V produces V
ofs
=
( − 5
.
480
± 0
.
001 ± 0
.
001)
=
( − 5
.
480 ± 0
.
002) V
.
If one of [o
ff
set ] is pressed and held, the o
ff
set is continuously
adjusted. The rate of the adjustment increases as the button is held.
If the value crosses the threshold
V
ofs
=
± 2
.
00 V
,
the rate changes
appropriately.
If both [o
ff
set ] and [o
ff
set ] buttons are pressed at the same time, the
resetting o
ff
set
o
ff
set is reset to 0.000 V.
1.2.4 Overload
There are two overload indicators, one OVLD LED in the IN-
PUT block and one OVLD LED in the OUTPUT block of the front
panel. The overload signal can also be asserted on the ¬ STATUS pin.
See Section 3.5.
SIM983 Scaling Amplifier