General Information; Specifications; Safety Considerations - HP 4937A Operating And Service Manual

MODEL 4937A
SECTION I
GENERAL INFORMATION
1-1. INTRODUCTION
1-2. This Operating and Service Manual contains information required to install, operate, test, adjust,
and service the Hewlett-Packard Model 4937A Transmission Impairment Measuring Set, Figure 1-1
shows the instrument and accessories supplied. Throughout the remainder of this manual the Model
4937A wili be referred to as HP 4937A or the instrument.
1-3. The Manual part number is listed on the title page. Also listed on the title page of this manual is
a Microfiche part number. This number can be used to order 4X 6 inch microfilm transparencies of
the manual. Each microfiche contains up to 96 photo-duplicates of the manual pages. The microfiche
package also includes the latest Manual Changes supplement as well as pertinent Service Notes.
1-4. SPECIFICATIONS
1-5. Instrument specifications are listed in table 1-1. These specifications are the performance
standards or limits against which the instrument is tested. Supplemental characteristics are shown in
the shaded areas or in italics and are intended to provide information useful in the application of the
instrument. These specifications are not warranted performance parameters. Performance tests are
listed in Section IV of this manual.
1-6. SAFETY CONSIDERATIONS
1-7. This product is a Safety Class 1 instrument (provided with a protective earth terminai), The in¬
strument and manual should be reviewed for safety markings and instructions before operation.
1-8. INSTRUMENTS COVERED 8Y THIS MANUAL
1-9. Attached to the instrument is a serial number plate. The serial number is in the form:
OOOOAOOOOO. It is in two parts; the first four digits and the letter are the serial prefix and the last
five digits are the suffix. The prefix is the same for all identical instruments; it changes only when a
change is made to the instrument. The suffix however, is assigned sequentially and is different for
each instrument. The contents of this manual apply to the instruments with the serial number
prefix(s) listed under SERIAL NUMBERS on the title page.
1-10. An instrument manufactured after the printing of this manual may have a serial number prefix
that is not listed on the title page, This unlisted serial number prefix indicates the instrument is dif¬
ferent from those described in this manual. The manual for this newer number is accompanied by a
yellow Changes Sheet supplement. This supplement contains ^'change information" that explains how
to adapt the manual to the newer instrument.