Tektronix 5110, Инструкция по эксплуатации

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Adjustment-5110
b. Apply a ground connection (short circuit) between
the junction of R885 and C890, and a ground test point.
See Fig. 3-1 for the junction and ground test point
locations.
c. Check —for a meter reading of +395 to +405
millivolts.
d. Disconnect the ground connection (short circuit)
from the junction and ground test point.
e. Disconnect the digital voltmeter.
NOTE
If the high-voltage power supply is within the
specified tolerance, proceed with part g. If the
adjustment is to be made, all remaining adjustments
in this procedure could be affected and should be
performed to verify the accuracy of all adjustments.
An insulated screwdriver must be used to adjust
variable components in this instrument, especially in
the high-voltage area, to prevent shorting voltages
to ground and damaging the instrument.
5. Adjust High-Voltage Power Supply
a. Press the POWER switch to turn off the oscilloscope
and return the oscilloscope to its normal upright position.
b. On the rear panel of the instrument, remove the two
cap nuts securing the cover over the crt socket, then
remove the cover (a5/16-inch nutdriver may be needed to
remove the cap
nuts).
c. Set the de voltmeter (vom) to measure at least -4000
volts de. Remove the insulating sleeve from the probe tip
of the test lead to be used for measuring the negative
voltage. Connect the voltmeter leads between a con­
venient chassis ground and the high-voltage test point.
See Fig. 3-2 for test point location. (The high-voltage lead
should be fully inserted through the crt socket cover so
that the lead connects to the test point without having to
hold it by hand).
d. Pull the POWER switch to turn on the oscilloscope.
e. Check—for a meter reading of -3400 volts, ±170
volts.
Fig. 3-2. Location of high-voltage test point.
f. Adjust —High Volts Adjust R275, using an insulated
screwdriver, for a meter reading of exactly —3400 volts.
See Fig. 3-3 for adjustment location.
g. Press the POWER switch to turn off the oscilloscope
before disconnecting the voltmeter.
h. Disconnect the de voltmeter and replace the cover
over the crt socket, reversing the procedure given in part b
of this step.
6. Adjust Intensity Range
a. Pull the POWER switch to turn on the oscilloscope.
b. Set the INTENSITY control fully counterclockwise.
Fig. 3-3. Locations of high-voltage, Intensity, and display
adjustments.
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