IET Labs, Inc. RLC Digibridge 1693, Руководство пользователя и обслуживания, Страница: 73 / 171

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1693 RLC Digibridge
Operation
To Hold the Range selected by Use of a Parameter
Key . Another way to get into the desired range is to
use a parameter key, thus:
1. Select ENTER function with the
[FUNCTION] key.
2. Press the appropriate parameter key (such
as Cs/D) repeatedly, watching the units
indicators.
The range advances with each repetition, enabling you
to determine the present range by the pattern of changes.
Notice that there is not always a change of unit
multiplier with each range change. (Refer to Table 3-6
on page 40.)
3. Press: [SHIFT][HOLD RANGE] to light the
RANGE HELD indicator.
(To return to the normal autoranging feature, press the
same two keys again , making the RANGE HELD
indicator unlit.)
To Hold Range by Number
. If you know the desired
range number (see Table 3-7 on page 43), use the special
function key as follows:
1. Select ENTER with the [FUNCTION] key.
2. For range 1, press: [l][=][SHIFT][SPECIAL][1]
3. For range 2, press: [2][=][SHIFT][SPECIAL][1]
4. For range 3, press: [3][=][SHIFT][SPECIAL][1]
5. For range 4, press: [4][=][SHIFT][SPECIAL][1]
Note: for autoranging, press: [0][=][SHIFT]
[SPECIAL][1].
3.5.8 Time Required for Obtaining
Median Values and Averaging
Accuracy can be enhanced, at the cost of increased
measurement time, by either or both of these meth-
ods. The time considerations and a brief instruction
for selecting each method (while in the ENTER
FUNCTION) are given here.
Median Value. This measurement time is somewhat
less than triple the single measurement time, because
three nearly complete measurements are made, from
which the Digibridge selects the median for final
results. To be more specific, each median-value
measurement requires approximately as much time as
three single measurements MINUS two of the three
settling or delay time intervals and also MINUS about
half of the calculation time. (The relative magnitudes
of settling time, delay time, and calculation time in
the single measurement cycle are illustrated in para-
graph 3.5.10.)
Enabling and disabling median-value selection is a
special function (paragraph 3.10). The enabling com-
mand is [1][=][SHIFT][SPECIAL][8] (See paragraph
3.6.4.)
Averaging . The measurement time is multiplied by
the number of measurements (2 to 255), specified
when averaging was programmed. To program the
Digibridge to average, for example, 8 measurements,
press [8][=][SHIFT][AVERAGE] (See paragraph
3.6.3.)
Both . If both median value and averaging are enabled
together, the measurement time is multiplied by al-
most three times the number specified when averaging
was programmed. (The Digibridge finds the medians
of groups of three measurements and then calculates
the average of the medians.)