Maintenance—2246 1Y and 2246 Mod A Service
INSPECTION. Inspect the internal portions of the
2246 1Y or 2246 Mod A for damage and wear, using
Table 6-3 as a guide. Repair deficiencies im
mediately. The corrective procedure for most visible
defects is obvious; however, particular care must be
taken if heat-dam aged components are found.
Since overheating usually indicates other trouble in
the instrument, it is important that the cause of over
heating be corrected to prevent further damage.
If any electrical component is replaced, conduct a
Performance Check for the affected circuit and for
other closely related circuits (see Section 4 for the
Performance C heck). If repair or replacement work
is done on any of the power supplies, conduct a
complete Performance Check and, if so indicated,
an instrument readjustment (see Section 5 for
Adjustment Procedure).
^ / V
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> CAUTION
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To prevent damage from electrical arcing, en
sure that circuit boards and components are
dry before applying power to the instrument.
CLEANING. To clean the interior, blow off dust with
dry, low-pressure air (approximately 9 psi). Remove
any remaining dust with a soft brush or a cloth
dampened with a solution of mild detergent and
water. A cotton-tipped applicator is useful for
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 of 1% mild detergent and 99% water as
follows:
1. Remove covers and shields to reach parts to be
cleaned
(see
Removal
and
Replacement
Instructions).
2. Spray wash dirty parts with the detergent-and-
water solution;
then
use
clean
water to
thoroughly rinse them.
3. Dry all parts with low-pressure air.
4. Dry all components and assemblies in an oven
or drying com partm ent using low-temperature
(125°F to 150°F) circulating air.
SWITCH CONTACTS. Switch contacts are perma
nently treated when assembled. Neither cleaning nor
other preventive maintenance is necessary, unless
the switch board is replaced or the switch assembly
has remained disassembled for a long period of
time.
LUBRICATION
A regular periodic lubrication program for the instru
ment is not necessary. Most of the potentiometers
used in this instrument are permanently sealed and
generally do not require periodic lubrication. The
backs of the front-panel knob guides have been
lubricated when assembled and will require lubri
cation again only when the front panel assembly is
replaced. Rotary switches are installed with proper
lubrication when assembled and will require lubri
cation only when the rotor is replaced.
SEMICONDUCTOR CHECKS
Periodic checks of the transistors and other
semiconductors in the oscilloscope are not recom
mended. The best check of semiconductor per
formance is actual operation in the instrument.
PERIODIC READJUSTMENT
To ensure accurate measurements, check the per
formance of this instrument every 2000 hours of
operation, or if used infrequently, once each year. If
you replace any components, it may be necessary
to readjust the affected circuits.
The silver-oxide
battery used in the 2246 1Y MUST be replaced
annually. Refer to Corrective Maintenance in this
section
for
more
information
on
battery
replacement.
Complete Performance Check instructions are given
in Section 4 of this manual; adjustment instructions
are given in Section 5. The Performance Check
Procedure can be helpful in localizing certain
troubles in the instrument. In some cases, minor
problems may be revealed or corrected by readjust
ment. If only a partial adjustment is performed, see
Table 5-1 (the interaction chart) for possible adjust
ment interaction with other circuits.
6 -4
Содержание 2246 1Y
Страница 13: ...2246A Service 7062 01 X The 2246 1Y or 2246 Mod A Portable Oscilloscope ...
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Страница 69: ...Theory of Operation 2246 1Y and 2246 Mod A Service 15 V 6081 07 3 32 Figure 3 4 Simplified Sweep Circuit ...
Страница 91: ...Theory of Operation 2246 1Y and 2246 Mod A Service 6081 12 6557 99 3 54 Figure 3 9 Power Supply block diagram ...
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Страница 278: ...Figure 9 5b Detailed 2246 1Y or 2246 Mod A block diagram part 2 R E ...
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Страница 304: ...A D D J U N 1991 ...
Страница 311: ...2246 1Y and 2246 Mod A Service WAVEFORMS FOR DIAGRAM 1 0 V r l III B f e I l i 6555 39 ...
Страница 314: ...15 14 13 12 11 10 9 8 7 6 5 12 11 10 9 8 7 AT117 A TI 271 1 2 3 4 5 6 6555 70 Figure 9 8 Hybrid pin identifiers ...
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Страница 321: ...2246 1Y and 2246 Mod A Service WAVEFORMS FOR DIAGRAM 2 SET READOUT CONTROL CCW OFF 6555 40 ...
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Страница 344: ...WAVEFORMS FOR DIAGRAM 5 2246 1Y and 2246 Mod A Service HORIZ MODE A A SEC DIV 2M S HOLDOFF MIN CCW ...
Страница 345: ...HORIZ MODE ALT A SEC DIV 2M s B SEC DIV 5 mS HOLDOFF MIN DELAY INTENSIFIED ZONE STARTS MIDSCREEN ...
Страница 347: ...BEV JUNE 1991 7062 18 ...
Страница 349: ...2246 1Y and 2246 Mod A Service WAVEFORMS FOR DIAGRAM 6 6555 43 I ...
Страница 354: ...A L B i C 1 D 1 E i F i G 1 2 3 4 5 6 7 8 2246 1Y AND 2246 MOD A _________A fc A A REV JUNE 1991 7062 19 ...
Страница 355: ...I BOARD LOCATION 8K 8J 8H 7H 8H 8H 7J 8D 7H 8H 8J 8J 7K 8K 10D 6L 6K 6L 6K 6G 5H I ...
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Страница 372: ...2246 1Y and 2246 Mod A Service WAVEFORMS FOR DIAGRAM 9 MORE ...
Страница 373: ... 6555 72 6557 88 ...
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Страница 376: ...SCHEM LOCATION BOARD LOCATION 2E 2B 7F 4B 4J 5D 3J 5C 4L 6D 3L 6C 5L 7D 3L 7D 3M 7D 5M 7D IB 1A 1C 1A 2B 1A 3B 1A ...
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Страница 387: ...WAVEFORMS FOR DIAGRAM 11 6555 73 6557 48 ...
Страница 394: ...WAVEFORMS FOR DIAGRAM 12 2246 1Y and 2246 Mod A Service i f I S 1 f c i 4 i ...
Страница 395: ...WAVEFORMS FOR DIAGRAM 12 cont 2246 1Y and 2246 Mod A Service ...
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Страница 400: ...REV JUNE 1991 7062 39 ...
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Страница 406: ...B 2246 IV AND 2246 MOD A ...
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