Section I Model 175A
Paragraphs 1-9 to 1-16
1-9. SPECIAL FEATURES. 1-15. AMBER FILTER.
1-10. Special features of the Model 175A include the 1-16. An amber filter (@ Stock No. 120A-83A) is
Hewlett-Packard internal-graticule crt, PRESET supplied with each oscilloscope which has a type P7
triggering, BEAM FINDER, and a cabinet which phosphor crt. The filter, when installed over the
serves both bench- and rack-mount requirements. face of the crt, improves visual observation of dis-
Optional plug-in units are provided for both the ver- plays such as single-shot phenomena or very low
tical and the time axis. The main vertical amplifier frequency applications. The filter provides the long
rise time is less than 7 nanoseconds which provides persistency characteristics desired for observation
maximum versatility for present and future plug-ins. of displays of this type. To install the filter, pro-
ceed as follows:
a. Remove front panel crt bezel.
1-11. CATHODE-RAY TUBE. b. Set filter into bezel, aligning larger rectangular
slots in edge of filter with guide metal posts on
1-12. The crt used in the Model 175A is a multi-grid bezel casting.
12-kvpost-accelerator type with the @ internal grati- c. Remove oscilloscope top cover.
cule which eliminates parallax, and an aluminized
phosphor. The gun structure provides a large 6x d. Loosen clamp at socket of crt.
10 cm distortionless viewing area as well as ex-
e. Carefully push CRT toward rear of instrument
tremely high deflection-plate sensitivity. to provide clearance for thickness of installed filter
(about 1/8 inch),
f. Replace bezel with filter and tighten bezel screws.
1-13. SPECIAL CONTROLS. g. Slide crt forward until light mask on front of
1-14. Special panel controls make the Model 175A crt just touches filter.
easy to operate. With SWEEP MODE in PRESET,
the sweep will synchronize internally on nearly all h. Tighten clamp to keep crt from turning; do not
signals. BEAM FINDER enables the operator to over-tighten clamp or tube damage may result.
locate the beam when it is off screen. SWEEP i. Obtain a free running trace and then adjust
MAGNIFIER increases the maximum sweep rate to TRACE ALIGNMENT until trace is aligned with
10 nsec/cm, calibrated in all positions. horizontal lines of graticule.
1.
1-4 |
ACEC
HEWLETT-PACKARD
