HP 400E, Руководство по эксплуатации и обслуживанию

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Models 400E/400EL
Section
I
SECTION
GENERAL
1-1. DESCRIPTION.
1-2. The -hp- Models 400E and 400EL are versatile
ac voltmeters and dB meters. Both models can be
used as ac to de converters or wide band amplifiers.
The Model 400E is primarily intended for voltage
measurements, whereas the Model 400EL is primarily
a dB meter. However, both meters indicate both volts
and dB. The 400E has a linear ac scale with a
logarithmic dB scale underneath, and the 400EL has a
linear dB scale with a logarithmic ac scale underneath.
Since the difference in scales is the only difference
between the two instruments, this manual will use the
term 400E/EL in reference to both instruments.
1-3. Figure 1-1 shows both the Model 400E and the
Mode1400EL. Table 1-1 is a list of specifications.
1-4. OPTIONS AVAI LABLE_
1-5. OPTIO N 01 (400E ONL Yl.
1-6. Option 01 places the dB scale uppermost for
greater resolution when making dB measurements.
INFORMATION
1-7. OPTION 02.
1-8. Option 0 2 adds a relative reference adjustment
to the 400E/EL. The REL. REF. control allows a
continuous reduction in sensitivity by a maximum of
3
dB in order to make relative voltage or dB
measurements.
1 -9. I N S TR U M E N T A N D M ANUAL
IDENTIFICATION.
1-10. Hewlett-Packard instruments are identified by
a two-section, eight-digit serial number (000·00000).
If the first three digits of the serial number on your
instrument do not agree with those on the title page
of this manual, change sheets supplied with the
manual will define differences between your
instrument and Model 400E/EL described in this
manual.
1-11. If a letter prefixes the serial number, the
instrument was manufactured outside the United
States.
Figure 1-1. Models 400E and 400EL AC Voltmeters
1-1