Tektronix 543B, Instruction Manual

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Calibration — Type 543B/RM543B
Fig. 5-3. Location of internal adjustments and test points for time base and crt circuit.
Fig. 5-4. Adjustment of GEOMETRY control.
Now set the Test Function switch to Gain Set and the
AMPLITUDE CALIBRATOR to 100 VOLTS. Connect a jumper
from the CAL OUT connector to the Ext input connector of
the TU-7. Adjust GAIN R520 for exactly 4 cm of vertical
separation between the two traces. Be sure measurements
are always made from the same side of the trace. Vary the
line voltage 10% above and below design center line volt­
age, the gain should not change more than 3%.
Set the AMPLITUDE CALIBRATOR to 2 VOLTS ond set the
Type TU-7 Test Function switch to Low Load. Adjust the
Type TU-7 Variable control for a 2-cm vertical separation
between the two traces. This adjustment is made using the
center 2-centimeter area of the crt.
Move the display up and down, and measure any changes
in apparent sensitivity at different points. The signal must
not be compressed or expanded more than 1.5 mm at either
the top or bottom extremes of the graticule.
Disconnect the jumper from the CAL OUT connector to
the Ext Input connector and center the trace. Vary the line
5-4