Tektronix PS 503A, Instruction Manual

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Section 3—PS 503A
ADJUSTMENT
Introduction
This adjustment procedure is to be used to restore the
PS 503A to original performance specifications. Adjust­
ment need not be performed unless the instrument fails to
meet the requirements listed in the Specification section,
or the Performance Check cannot be completed satisfac­
torily.
Services Available
Tektronix, Inc. provides complete instrument repair
and adjustment at local Field Service Centers and at the
Factory Service Center. Contact your local Tektronix Field
Office or representative for further information.
d. Install all TM 500-series equipment, including the
PS 503A into the power module.
e. Connect all test equipment to a suitable line voltage
source.
f. Turn on all test equipment and allow at least twenty
minutes for the equipment to warm-up and stabilize.
g. Set the autotransformer to the nominal line voltage
setting.
Test Equipment Required
The test equipment listed in Table 2-4 or equivalent, is
required for adjustment of the PS 503A. Specifications
given for the test equipment are the minimum necessary
for accurate adjustment and measurement. All test equip­
ment is assumed to be correctly calibrated and operating
within specification.
If other test equipment is substituted, control settings
or calibration setup may need to be altered to meet the
requirements of the equipment used.
Initial Control Settings
Set the following controls during warm-up time:
PS 503A Dual Power Supply
- VOLTS (coarse and fine)
+ VOLTS (coarse and fine)
CURRENT
LIMIT
Plus supply
Minus supply
VOLTS DUAL TRACKING
fully ccw
fully cww
fully ccw
fully ccw
pushed in and
fully ccw
Preparation
a Remove the left-hand and right-hand side covers of
the PS 503A to gain access to the component side of the
circuit boards. Pull the rear end of the side cover outward
from the side of the instrument (the cover snaps into
place).
b. Install the PS 503A into the far right (high power)
power module compartment, or if appropriate, connect
the PS 503A to the power module by means of the flexible
plug-in extender. If a flexible extender is used, current
limiting switch S95 must be engaged in the maximum
current (HI) position. See Fig. 3-1 for switch location.
c. Set the power module for the line voltage to be
applied (see power module manual) and connect it to the
autotransformer, then connect the autotransformer to the
line voltage source. Be sure that the power switch is off.
Fig. 3-1. Location of +20 V and —20 V adjustment.
3-1