Model 140A Section 11
Paragraphs 2-1 to 2-21
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I SECTION II
INSTALLATION
2-1. INCOMING INSPECTION. the Model 140A, choose a location that provides at
least three inches of clearance around rear and sides
2-2. MECHANICAL INSPECTION. Upon receipt
of instrument.
of the Model 140A, check the contents of the carton
and inspect the instrument for any obvious damage
I 2-13. AIR FILTER.
received in shipment. If damage is evident, file a
claim with the carrier. Refer to the warranty sheet 2-14. The filter should be cleaned periodically to
at the rear of this manual for additional information. ensure proper cooling. After cleaning, the air
Keep the packing material until an operational check filter, located on the rear of the instrument, should
has been completed. be coated with a filter adhesive such as Filter Coat
No. 3 from Research Products Co. Refer to Para-
2-3. OPERATIONAL CHECK. Refer to Section V graph 5-32 for cleaning procedures.
(Paragraph 5-3) for a performance check to verify
that operation is within published specifications. This 2-15. INSTRUMENT MOUNTING.
check requires that either a single large plug-in or
2-16. MODULAR CABINET,
two small plug-ins be installed.
2-17. The Model 140A is shipped from the factory
as a bench instrument with the tilt stand, feet, and
2-4. POWER REQUIREMENTS. plastic trim in place. The top and bottom cabinet
covers can be removed, giving complete accessibility
2-5. The Model 140A requires a power source of
115 or 230 volts *lo%, single phase, 50 to 60 cps, to all components and adjustments. Sufficient space
should be allowed around the cabinet for adequate
which can deliver approximately 300 watts.
circulation air.
CAUTION 2- 18. RACK MOUNTING.
Be sure to set the 115-230 volt switch for 2-19. Prepare the cabinet for rack mounting as
the line voltage to be used. The power illustrated in Figure 2-1. All necessary hardware
supplies may be damaged if this switch is is in the shipping carton with the instrument. After
set to the wrong position. preparation, lift the instrument into place, and
secure mounting flanges to rack with appropriate
2-6. 230-VOLT OPERATION. screws. Allow adequate ventilation for the instru-
ment in the rack.
2-7. If the instrument is to be operated from a 230-
volt source, set the switch on the rear of the instru-
2-20. INSTALLATION OF AMBER FILTER.
ment to 230. The line fuse, located behind the rear
i panel, is accessible by removing the bottom cover, 2-21. An amber filter (@ Stock No. 120A-83A) is
and should be replaced with a 2-amp slow-blow fuse supplied with oscilloscopes which have a CRT with
(supplied). (A 4-amp slow-blow fuse is used with type P7 phosphor. This filter improves the visibility
11 5-volt operation.) of displays such as single-shot or very low frequency
phenomena. The filter improves the long persistency
2-8. THREE CONDUCTOR POWER CABLE. characteristics of the trace when making visual
2-9. To protect operating personnel, the National observations of this type of display. To install the
filter:
Electrical Ma. :facturers' Association (NEMA) re-
commends that the instrument panel and cabinet be a. Remove front panel CRT bezel.
grounded. This instrument is equipped with a three-
b. Set filter into bezel, aligning larger rectangular
conductor power cable which, when plugged into an
appropriate receptacle, grounds the instrument. The slots in edge of filter with guide metal posts of bezel
casting.
offset pin on the power cable three-prong connector
is the ground pin. To preserve the protection feature c. Loosen clamp at socket of CRT.
when operating the instrument from a two-contact
d. Carefully push CRT toward rear of the instru-
outlet, use a three-prong to two-prong adapter and ment to provide clearance for thickness of installed
connect the green pigtail to ground.
filter (about 1/8 inch).
e. Replace bezel.
2-10. COOLING.
2-11. VENTILATION REQUIREMENTS. f. Slide CRT forward until light mask on front of
CRT just lightly touches filter.
2-12. The Model 140A uses a forced-air cooling
system to maintain reasonable operating temperatures g. Tighten clamp just enough to keep CRT from
turning.
within the cabinet. The air intake and filter are
located on the rear of the instrument. When installing h. Check trace alignment. See Paragraph 3-7.
01638-1 2- 1 |
ACEC
HEWLETT-PACKARD
