Tektronix 2225, Руководство оператора

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Operation
VERTICAL CONTROLS
When making voltage measurements, rotate the VOLTS/DIV CAL
control fully clockwise (in detent). Best accuracy can be achieved
by setting the VOLTS/DIV control for the largest display possible.
Input Coupling
For most applications use DC input coupling. This mode is com­
patible with the standard-accessory, high-impedance probes
and it displays logic levels and dc levels of static signals.
Use GND input coupling to show where the 0-volt level will be
located when you shift to DC coupling.
Use AC coupling for the special cases where you need to see
small signals on large dc voltage levels.
Channel Selection
With the three VERTICAL MODE buttons, you can display com­
binations of the two vertical channels. When C H 1 is selected, the
other two MODE switches are not active. When CH 2 is selected,
the middle MODE switch (NORM/CH 2 INVERT) becomes active.
And when BOTH channels are selected for display, all three
MODE switches are active.
ADD and INVERT
Select ADD mode to display the algebraic sum of the CH 1 and
CH 2 signals. When you use ADD, the CH 1 and CH 2 VOLTS/DIV
settings should be equal.
Selecting CH 2 INVERT changes the sense of the CH 2 waveform.
This allows you to see the difference between the CH 1 and CH 2
signals on the ADD trace.
CHOP or ALT?
When BOTH channels are selected, the display is time-shared.
The CHOP mode displays each channel for a short time and mul­
tiplexes during the sweep to give the appearance of displaying
both channels at once. This mode (CHOP) works better than ALT
for sweep speeds slower than 1 ms per division and for low-repeti-
tion-rate signals that make the display flicker "(up to 2 pus/division).
The ALT mode displays each channel for the duration of a com­
plete sweep. It gives a cleaner display of multiple channels than
CHOP does and is usually preferred at moderate to high sweep
speeds.
2225 Operators 2-7