Enabling/Disabling The Filter - Keithley 2001 Operator's Manual

Front Panel Operation
Choosing the filter parameters for each function follows the
same procedure. You can program a digital filter as follows:
1. There are three ways to display a filter configuration
menu:
•To configure the filter of the present function, just press
CONFIG, then FILTER.
•To configure the filter of another function and remain
in the present function, press CONFIG, and the
appropriate function key, then select FILTER from its
menu.
•To configure the filter of another function and change
to that function, press the appropriate function key,
and CONFIG, then FILTER.
2. As an example, consider the DCV digital filter menu.
Display the CONFIGURE DCV menu by pressing the
CONFIG key and then the DCV key.
3. Use the cursor keys (
FILTER and press ENTER to access the following
menu:
DCV DIGITAL FILTER
AUTO AVERAGING ADVANCED
AVERAGING-MODE
AUTO
This menu item selects auto filtering. When chosen, auto
filtering enables the filter parameters listed in
the function you are presently configuring. Note that
selecting AUTO immediately enables the filter for that
function when the state listed in
case, if you are configuring the filter for the present
measurement function, the FILT annunciator comes on.
AVERAGING
Use this selection for a non-windowed averaging filter. A
message indicating the presently set number of reading
conversions to average (the "stack" size) is displayed:
AVG:010 RDGS (1-100)
1. To retain the displayed number, press ENTER or EXIT.
2. To set a different number, use the cursor keys (
) to select the digits, and the RANGE  and 
keys to increment and decrement the digits. Press EN-
TER when done.
Note that the number of reading conversions selected
for the averaging filter type is coupled to that for the ad-
vanced filter type.
3-90
and ) to place the cursor on
Table 3-17
Table 3-17 is ON. In this
ADVANCED
This selection is for an averaging filter with a noise window.
(It is not available with dB or dBm units, ratio or delta,
temperature or frequency.) A message indicating the
presently set number of reading conversions to average (the
"stack" size) is displayed:
ADV:010 RDGS (1-100)
1. To retain the displayed number, press ENTER. To set a
different number, use the cursor keys (
lect the digits, and the RANGE  and  keys to in-
crement and decrement the digits. Press ENTER when
done.
Note that the number of reading conversions selected
for the advanced filter is coupled to that for the averag-
ing filter.
2. The next message is for the maximum noise window,
which is expressed in percent of range, as follows:
LEVEL = 00.000000%RNG
This is the plus or minus percentage of range window
around the first reading conversion in the stack. To set a
different percentage, use the cursor keys and RANGE
keys. Press ENTER when done.
AVERAGING-MODE
for
This selection determines the mode of a digital filter for a
measurement function, either a moving or repeating average.
The AVERAGING MODE menu is shown as follows; its
present selection is highlighted:
AVERAGING MODE
MOVING
MOVING: This item selects a moving filter, where a new
reading conversion is shifted into a stack as the oldest
conversion is shifted out (FIFO). When the stack is full, a
simple average is taken to yield a reading.
REPEAT: This menu item selects a repeating filter, where
an average of a selected number of reading conversions is
and
taken for each reading.
3.9.6

Enabling/disabling the filter

The FILTER key toggles the filter on and off for the present
measurement function. With the FILT annunciator on, the
filtering action depends on the selections chosen in the
FILTER menu for the present function. With the FILT
REPEAT
2001-900-01 Rev. K/ August 2010
and ) to se-