Extech Instruments 400790A User Manual page 10

8. Address: Displays current number of data surveys stored in memory.
9. Bar graph: Displays the sound level as a bar graph. (The display is updated every 100ms)
10. Level range: Displays the upper and lower limit of the bar graph. Can be changed with the
 LEVEL  button.
11. Under‐range indication: When a signal is under‐range the UN symbol will appear on the
screen. Use the  LEVEL  button to decrease the level range setting. If processed data is
under‐range the UN indication will remain on the screen until the next processing
measurement is started.
12. Overload indication: When a signal overload is detected, the screen will display OV for at
least 1 second. Use the  LEVEL  button to increase the level range setting. If processed
data is over range the OV indication will remain on the screen until the next processing
measurement is started.
13. Main channel frequency weighting: Indicates the main channel frequency characteristic. A:
A‐weighting, C: C‐weighting, Z: Z‐weighting (flat response)
14. Main channel time weighting: Indicates the main channel time weighting characteristic.
F: Fast (125ms), S: Slow (1000ms), τ: (10ms), I: Impulse (35ms)
15. Main channel level display: Displays the measured sound level in the main channel.
(The display is updated every second).
16. Sub channel frequency weighting: Indicates the sub channel frequency weighting
characteristic. A: A‐weighting, C: C‐weighting, Z: Z‐weighting (Flat response).
The sub channel frequency weighting can be set from the menu screen.
17. Sub channel time weighting: Indicates the sub channel time weighting characteristic.
F: Fast (125ms), S: Slow (1000ms), τ: (10ms), I: Impulse (35ms)
18. Sub channel level display: Shows the measured sound level in the sub channel.
(The display is updated every second)
19. Power status: When operating the meter on battery power the yellow segments will
decrease as the battery power drains. When the segment starts to flash, replace batteries.
Yellow Yellow
Battery good ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐> Replace Segment flashes (critical)
20. Manual store full: When the manual stored memory is full, the MFul symbol is displayed.
The manual data store capacity is 250 sets.
21. Auto store full: When the auto store memory is full, the AFul symbol is displayed. The auto
store capacity is 250 blocks.
22. Comparator ON: When the comparator function has been set to ON and a signal exceeds
the comparator output jack, the indicator Cmp will appear on the display. A signal will
output from the comparator output jack on the side panel (open collector).
23. Current date: Displays the current date
24. Current time: Displays the current time
Yellow Yellow
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