Tektronix CA PLUG-IN, Instruction Manual

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Connect a jumper between the C A L OUT
connector o f the oscilloscope and both of the
vertical input connectors of the Type CA Unit.
With .1 V O LT of calibrator applied to each
channel adjust the GAIN ADJ, of each channel,
fo r 2 cm of vertical deflection on the CRT.
9. Check Operation of AC-DC Switch
With all Controls set as in Step 8 position
the bottom of the calibrator waveforms to the
center graticule line.
Now switch the AC-
DC switch to AC. The waveforms should shift
down so that the center graticule line w ill
now be approximately through the center of
the waveforms.
10. Check ADDED ALG EBR AICALLY
Position of MODE Switch
Set plug-in Controls to:
AC-DC (A and B) DC
MODE ADDED
ALG EBRA­
IC A L L Y
With the same amount of calibrator Signal
s till applied as in step 9 check to see that
there is 4 cm of deflection on the crt.
Now apply one volt of calibrator Signal from
the oscilloscope to each of the vertical inputs
o f the Type CA Unit. Turn the A channel
P O L A R IT Y switch to INVERTED.
The two
Signals should now cancel each other out within
1 cm. You may adjust the V E R TIC AL POSITION
Controls to accomplish this cancellation. If
the cancellation just described doesn't take
place, reset the A channel P O L A R IT Y switch
to NORMAL and the B channel PO LA R IT Y
switch to INVERTED. Now check fo r proper
cancellation. The unit is satisfactory if either
condition w ill permit the proper cancellation
of the Signal.
11. Checking V O L T S / C M Switch
Position
Reset the plug-in Controls as follows:
MODE ALTERNATE
P O L A R IT Y (A and B) NORMAL
Connect a jumper from the C A L OUT con­
nector of A channel of the plug-in. Check for
the correct deflection in each Position of the
VOLTS/CM switch. Now remove the jumper
from A and connect it to B channel. Run
through the check on this channel as you did
on A channel.
Note
At the factory the accuracy of
the VOLTS/CM switch is checked
with an AM PLITUDE CALIBRATOR
Standardizer, which employs 1/4%
resistors.
V O LTS /C M
Switch
A M P LIT U D E
C A L IR R A T O R VOLTS
V E R T IC A L C R T
D E FLE CT IO N
.05
.2 4 cm
.1 .2
2 cm
.2 .5
2.5 cm
.5 2 4 cm
1 2
2 cm
2 5
2.5 cm
5 20
4 cm
10 20
2 cm
20 50
2.5 cm
AA
1
5-4
Calibration - Type CA