Algebraic Addition Measurement - Tektronix 2212 User Manual

Non-Storage Examples
Algebraic Addition
Measurement
3-6
Toggle the Vertical MODE to ADD. The waveform displayed
represents the algebraic sum of the signals applied to the
CHl OR X and CH2 ORY input connectors (CHl + CH2).
If the CH 2 INVert switch is in the INVert position, the resulting
waveform is the difference of the two input signals (CHl- CH2).
The total deflection factor in ADD mode is equal to the deflection
factor indicated by either VOL TS/DIV switch when both
VOL TS/DIV switches are set to the same setting.
In the ADD mode, you can also provide a de offset for viewing an
ac signal riding on top of a de level.
The following general precautions should be observed when using
the ADD mode:
1.
Do not exceed the input voltage rating of the oscilloscope.
2. Do not apply signals that exceed the equivalent of about eight
times the VOL TS/DIV switch setting, since large voltages may
distort the display. For example, with a VOL TS/DIV switch
setting of 0.5 V, the voltage applied to the input channel
should not exceed 4 V.
Example:
Suppose the graticule center line as
O
V, and the CH 1 signal is at a
two-division, positive de level (see Figure3-3A).
a. Two divisions X VOL TS/DIV switch setting
=
DC-level
value.
b. Apply a negative de level to the CH 2 ORY connector (or a
positive level, using the CH 2 INVERT switch) of the value as
determined in step a. (see Figure 3-3B).
c. Toggle the Vertical MODE switch to ADD and place the result-
ing display within the operating range of the Vertical POSI-
TION controls (see Figure 3-3C).
Measurement Examples