HP EPM E4418A, Руководство пользователя

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HP4402.book : chapter2.fm 20 Tue Apr 22 15:20:23 1997
Power Meter Operation
Setting the Units of Measurement
2-20 HP EPM-441A User’s Guide
Setting the Units of Measurement
The “dBm/W” menu is used to select the measurement units on the
currently selected window. These can either be logarithmic (dBm or dB) or
linear (Watt or %) units.
sets the measurement units to dBm
(logarithmic units). Table 2-2 shows which units are applicable to the
individual measurement modes.
Press , then select the unit of measurement from , , or
. Softkeys which cannot be selected in your particular mode of operation
appear with their text grayed out.
Note
When the unit of measurement is set to Watt, it is possible that
negative power measurements may be displayed when measuring
low power levels.
Table 2-2: Measurement Units
1. When relative mode is on (that is,
, is “
On
”)
, the
measurement is compared to a reference value.
Measurement
Mode
Relative Mode Off Relative Mode On
1
Linear Log Linear Log
Single Channel Watt dBm % dB
Preset
Local
dBm/W
dBm W dB
%
Rel
Offset
Rel Off On