TECPEL OS Series User Manual page 73

OS Series Handheld DSO & DMM
screen when the format is dB.
▲/▼
— CH2 Volts/Div
▲/▼
— FFT Zero
▲/▼
— FFT dB Scale

One of the following two prompts circularly will display at the bottom-left of the screen
when the format is Vrms.
▲/▼
— CH2 Volts/Div
▲/▼
— FFT Zero
Press VOLTS POSITION (red) and the screen show as follows:
▲/▼
—CH1 OFF
9. When FFT source is CH1:

If left bottom of the screen displays "
▼(red) button to adjust dB value of each DIV, including 1dB, 2dB, 5dB, 10dB,
20dB;

If left bottom of the screen displays "
▼(red) button to adjust voltage of CH1, and "CH1 2v~ "shows in left bottom of
the screen;

If left bottom of the screen displays "
(red) button to adjust the position of the waveform along the vertical position such
as "FFT 1.20 divs" which means the pink cursor departures from the center line for
1.20 DIV, press VOLTS POSITION (red) to display "
"CH1 20dB" shows on the left bottom, that is the arithmetic product is 24.0dB.
The operation steps are the same as FFT source CH2.
10. Press OPTION (yellow), the following prompts shows on the left bottom on the screen.
◄/►
— Time Base
▲/▼
— Trig
Or
◄/►
— Time
▲/▼
— Trig
8-Advanced Function of Oscilloscope
▲/▼
—FFT dB Scale ", press ▲(red) and
▲/▼
—CH1 Volts/Div " , press ▲(red) and
▲/▼
—FFT Zero", press ▲ (red) and ▼
▲/▼
68
—FFT dB Scale ",