HP 8572A, Руководство пользователя

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Purp ose This test measures the relativ e on-screen linear scale delity .
Note
Y ou m ust complete this test b efore y ou p erform an y amplitude
accuracy test.
Description \Linear Fidelit y" relies on the attenuator accuracy of the
HP 3335A syn thesizer/level generator and is measured in the display
CR T's upp er nine divisions. Although linear delity is not directly
sp ecied for the HP 8572A microw a v e EMI receiv er, it is one of the
con tributors to absolute amplitude accuracy in linear scale mo de.
The unit under test is set for a reference lev el of +13 dBm, and the
resolution bandwidth or QP A (CISPR) bandwidth to b e tested.
The lev el generator amplitude is adjusted to set the signal at the
reference lev el. The dierence b et w een the lev el generator and
marker amplitudes establishes a reference error at this p oint.
The lev el generator is stepp ed do wn in 10% of full scale incremen ts
un til the signal is nine divisions b elow the top of the screen. The
amplitude dierence b et w een the lev el generator and the display ed
trace a v erage is measured at eac h lev el generator step. The dierence
b et w een the amplitude error at eac h lev el generator step and the
reference error is the linear delity of the EMI receiv er system.
T est Settings
F unction Settings
RF FREQ 30 MHz
RFPS (atten) 43 dB
EMI receiv er system (input) receiv er INPUT 1
SA (atten) 10 dB
QP A lter 200 Hz 9 kHz, 120 kHz
RES BW 10 Hz to 3 MHz (1, 3, 10 sequence)
Scale Linear
REF LEVEL 120 dBV
Linear delity for the EMI receiv er system is tested to the follo wing
limits:
Linear Fidelity T est Limits
Signal Lev el
(% of full scale)
Linear Fidelity
(dB)
100 % Reference
10 % to <100 % 63.0 %
3-8 T est Descriptions HP 8572A EMI Receiv er User's Guide