Tektronix 2213, Инструкция по эксплуатации

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Maintenance-2213 Service
CLEANING. To clean the interior, blow o ff dust with
dry, low-pressure air (approximately 9 psi). Remove any
remaining dust w ith a soft brush or a cloth dampened with
a solution o f m ild detergent and water. A cotton-tipped
applicator is useful fo r cleaning in narrow spaces and on
circuit boards.
If these methods do not remove all the dust or dirt,
the instrument may be spray washed using a solution
o f 5% m ild detergent and 95% water as follows:
1. Gain access to the parts to be cleaned (see "Removal
and Replacement Instructions").
2. Spray wash d irty parts w ith the detergent-and-water
solution; then use clean water to thoroughly rinse them.
3. Dry all parts w ith low-pressure air.
SWITCH CONTACTS. The Vertical and Horizontal
attenuators in this instrument are circuit-board mounted
rotary switches. When cleaning them, care must be exer­
cised to preserve their high-frequency characteristics.
Switch maintenance is seldom necessary, but if it is
required, use the following cleaning method and observe
the stated precaution.
Use only h o t deionized o r distilled water, 55 ° C
(131° F), to dean a rotary switch in this instrument.
Tap water contains im purities which are le ft as
residuals after evaporation.
1. Spray hot water into the slots at the top o f each
switch housing while rotating the switch control knob.
Spray only fo r approximately five seconds, using an
atomizing spray device.
2. Dry both the switch and the circuit board on which
it is mounted, using dry low-pressure air.
3. Bake the switch and the circuit board at 75°C
(167°F) fo r 15 minutes to eliminate all moisture.
4. Spray a very small amount (only about a 1/2-second
squirt) o f a recommended lubricant, such as No Noise,
into the slots at the top of the switch housing.
5. Rotate the switch control knob about 180° and
again spray a very small amount o f lubricant into each slot.
LUBRICATION
Most o f the potentiometers used in this instrument are
permanently sealed and generally do not require periodic
lubrication. A ll switches, both rotary- and lever-type,
are installed w ith proper lubrication applied where neces­
sary and w ill rarely require any additional lubrication.
Therefore, a regular periodic lubrication program fo r the
instrument is not recommended.
SEMICONDUCTOR CHECKS
Periodic checks o f the transistors and other semi­
conductors in the oscilloscope are not recommended.
The best check o f semiconductor performance is actual
operation in the instrument.
PERIODIC READJUSTMENT
To ensure accurate measurements, check the perform­
ance o f this instrument after every 2000 hours o f operation,
or if used infrequently, once each year. In addition, replace­
ment o f components may necessitate readjustment o f the
affected circuits.
Complete Performance Check and Adjustment instruc­
tions are given in Sections 4 and 5. The Performance
Check Procedure can also be helpful in localizing certain
trouble in the instrument. In some cases, m inor problems
may be revealed or corrected by readjustment. If only a
partial adjustment is performed, see the interaction chart.
Table 5-1, fo r possible adjustment interactions w ith other
circuits.