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91年11月28日
ES51977
3 3/4 AUTO EASY
Continuity Check
The continuity check is the same as the 399.9Ω range of the resistance
measurement mode (manual mode). If the bargraph number <=3 ,there will
2.0 KHz signal comes out from BUZOUT pin, if the bargraph number >=4,
there will be no beep exist.
Diode Measurement
Use the DCV 3.999V range of voltage measurement mode (manual mode ).
If the test circuit is open or the device (diode) under test is larger than 2V,
the LCD display will show "OL",but the bargraph will show the real
detected voltage.
Frequency Counter
The timebase of ES51977 is derived by a clock oscillator.
The timebase of counter is :
4,000,000
T
counter =
F
osc
Thus , the counter will operate with a 1 second timebase when a
4MHz oscillator is used. For accurate frequency measurement,a
crystal oscillator is recommended. The frequency counter can
automatically or manually select the proper range. Autorange
operation extends over five decades from 1 Hz to 39.99MHz.
Range
Full Scale
FR1
FR2
FR3
FR4
FR5
3.999 KHZ
39.99 KHZ
399.9 KHZ
3.999 MHZ
39.99 MHZ