ETS-Lindgren HI-1710 Microwave Measurement System (Archived) - Manual (Page 17)

Page — 12 HI n 1710 Manual
will reset to the lowest range (1 mW/cm 2 ).
The range selection switches feature wrap-around
operation which means that when the instrument is in its
lowest range and the left or lower range (<) switch is
pressed, the instrument will move to the auto-range
setting. When the instrument is in auto-range and the
right or increase range switch (>) is pressed, the
instrument will move to the 1 mW/cm
2 setting.
Filter
The HI-1710 is internally programmed with four response
times (filters). This digital filtering changes the way the
instrument responds to rapidly changing RF or leakage
levels. Refer to section 5.0 (Theory of Operation). Filters
are selected by pressing the right or left filter select
switches located beneath the filter selection indicating
LEDs on the front panel.
Filter 1 is equivalent to the "SLOW" response mode on
analog meters. This is the default setting and is the
setting used for most hand scanning of microwave ovens.
This setting responds more slowly to rapidly changing RF
or leakage levels and tends to average the response to
peak levels caused by oven mode stirring devices. This
response characteristic is designed to meet the CDRH
requirement that an instrument respond to a step CW
microwave input to 90% of its steady state reading
within a maximum of three seconds while still providing
maximum smoothing of RF peaks.
Filter 2 is equivalent to the "FAST" response mode on
analog meters. The filter selection is used for observing
rapid variations in RF leakage and evaluating the effect of
stirrer modulation on leakage.
Archived 4/2/10